Moon Archives

September 20, 2015August 11, 2016 by Matt Williams

The Moon

Look up in the night sky. On a clear night, if you’re lucky, you’ll catch a glimpse of the Moon shining in all it’s glory. As Earth‘s only satellite, the Moon has orbited our planet for over three and a half billion years. There has never been a time when human beings haven’t been able to look up at the sky and see the Moon looking back at them.

As a result, it has played a vital role in the mythological and astrological traditions of every human culture. A number of cultures saw it as a deity while others believed that its movements could help them to predict omens. But it is only in modern times that the true nature and origins of the Moon, not to mention the influence it has on planet Earth, have come to be understood.

Size, Mass and Orbit:

With a mean radius of 1737 km and a mass of 7.3477 x 10²² kg, the Moon is 0.273 times the size of Earth and 0.0123 as massive. Its size, relative to Earth, makes it quite large for a satellite – second only to Charon‘s size relative to Pluto. With a mean density of 3.3464 g/cm³, it is 0.606 times as dense as Earth, making it the second densest moon in our Solar System (after Io). Last, it has a surface gravity equivalent to 1.622 m/s², which is 0.1654 times, or 17%, the Earth standard (g).

The Moon’s orbit has a minor eccentricity of 0.0549, and orbits our planet at a distance of between 356,400-370,400 km at perigee and 404,000-406,700 km at apogee. This gives it an average distance (semi-major axis) of 384,399 km, or 0.00257 AU. The Moon has an orbital period of 27.321582 days (27 d 7 h 43.1 min), and is tidally-locked with our planet, which means the same face is always pointed towards Earth.

Structure and Composition:

Much like Earth, the Moon has a differentiated structure that includes an inner core, an outer core, a mantle, and a crust. It’s core is a solid iron-rich sphere that measures 240 km (150 mi) across, and it surrounded by a outer core that is primarily made of liquid iron and which has a radius of roughly 300 km (190 mi).

Around the core is a partially molten boundary layer with a radius of about 500 km (310 mi). This structure is thought to have developed through the fractional crystallization of a global magma ocean shortly after the Moon’s formation 4.5 billion years ago. Crystallization of this magma ocean would have created a mantle rich in magnesium and iron nearer to the top, with minerals like olivine, clinopyroxene, and orthopyroxene sinking lower.

The mantle is also composed of igneous rock that is rich in magnesium and iron, and geochemical mapping has indicated that the mantle is more iron rich than Earth’s own mantle. The surrounding crust is estimated to be 50 km (31 mi) thick on average, and is also composed of igneous rock.

The Moon is the second densest satellite in the Solar System after Io. However, the inner core of the Moon is small, at around 20% of its total radius. Its composition is not well constrained, but it is probably a metallic iron alloy with a small amount of sulfur and nickel and analyses of the Moon’s time-variable rotation indicate that it is at least partly molten.

*Artist concept illustration of the internal structure of the moon. Credit: NOAJ*

The presence of water has also been confirmed on the Moon, the majority of which is located at the poles in permanently-shadowed craters, and possibly also in reservoirs located beneath the lunar surface. The widely accepted theory is that most of the water was created through the Moon’s interaction of solar wind – where protons collided with oxygen in the lunar dust to create H²O – while the rest was deposited by cometary impacts.

Surface Features:

The geology of the Moon (aka. selenology) is quite different from that of Earth. Since the Moon lacks a significant atmosphere, it does not experience weather – hence there is no wind erosion. Similarly, since it lacks liquid water, there is also no erosion caused by flowing water on its surface. Because of its small size and lower gravity, the Moon cooled more rapidly after forming, and does not experience tectonic plate activity.

Instead, the complex geomorphology of the lunar surface is caused by a combination of processes, particularly impact cratering and volcanoes. Together, these forces have created a lunar landscape that is characterized by impact craters, their ejecta, volcanoes, lava flows, highlands, depressions, wrinkle ridges and grabens.

The most distinctive aspect of the Moon is the contrast between its bright and dark zones. The lighter surfaces are known as the “lunar highlands” while the darker plains are called maria (derived from the Latin mare, for “sea”). The highlands are made of igneous rock that is predominately composed of feldspar, but also contains trace amounts of magnesium, iron, pyroxene, ilmenite, magnetite, and olivine.

*LROC Wide Angle Camera (WAC) mosaic of the lunar South Pole region, width ~600 km. Credit: NASA/GSFC/Arizona State University.*

Mare regions, in contrast, are formed from basalt (i.e. volcanic) rock. The maria regions often coincide with the “lowlands,” but it is important to note that the lowlands (such as within the South Pole-Aitken basin) are not always covered by maria. The highlands are older than the visible maria, and hence are more heavily cratered.

Other features include rilles, which are long, narrow depressions that resemble channels. These generally fall into one of three categories: sinuous rilles, which follow meandering paths; arcuate rilles, which have a smooth curve; and linear rilles, which follow straight paths. These features are often the result of the formation of localized lava tubes that have since cooled and collapsed, and can be traced back to their source (old volcanic vents or lunar domes).

Lunar domes are another feature that is related to volcanic activity. When relatively viscous, possibly silica-rich lava erupts from local vents, it forms shield volcanoes that are referred to as lunar domes. These wide, rounded, circular features have gentle slopes, typically measure 8-12 km in diameter and rise to an elevation of a few hundred meters at their midpoint.

Wrinkle ridges are features created by compressive tectonic forces within the maria. These features represent buckling of the surface and form long ridges across parts of the maria. Grabens are tectonic features that form under extension stresses and which are structurally composed of two normal faults, with a down-dropped block between them. Most grabens are found within the lunar maria near the edges of large impact basins.

Rima Ariadaeus as photographed from Apollo 10. The crater to the south of the rille in the left half of the image is Silberschlag. The dark patch at the top right is the floor of the crater Boscovich. Credit: NASA

Impact craters are the Moon’s most common feature, and are created when a solid body (an asteroid or comet) collides with the surface at a high velocity. The kinetic energy of the impact creates a compression shock wave that creates a depression, followed by a rarefaction wave that propels most of the ejecta out of the crater, and then a rebounds to form a central peak.

These craters range in size from tiny pits to the immense South Pole–Aitken Basin, which has a diameter of nearly 2,500 km and a depth of 13 km. In general, the lunar history of impact cratering follows a trend of decreasing crater size with time. In particular, the largest impact basins were formed during the early periods, and these were successively overlaid by smaller craters.

There are estimated to be roughly 300,000 craters wider than 1 km (0.6 mi) on the Moon’s near side alone. Some of these are named for scholars, scientists, artists and explorers. The lack of an atmosphere, weather and recent geological processes mean that many of these craters are well-preserved.

Another feature of the lunar surface is the presence of regolith (aka. Moon dust, lunar soil). Created by billions of years of collisions by asteroids and comets, this fine grain of crystallized dust covers much of the lunar surface. The regolith contains rocks, fragments of minerals from the original bedrock, and glassy particles formed during the impacts.

Bootprint in the lunar regolith left behing by the Apollo 11 crew. Credit: NASA — The historic boot print left behind by the Apollo 11 crew in the lunar regolith. Credit: NASA

The chemical composition of the regolith varies according to its location. Whereas the regolith in the highlands is rich in aluminum and silica, the regolith in the maria is rich in iron and magnesium and is silica-poor, as are the basaltic rocks from which it is formed.

Geological studies of the Moon are based on a combination of Earth-based telescope observations, measurements from orbiting spacecraft, lunar samples, and geophysical data. A few locations were sampled directly during the Apollo missions in the late 1960s and early 1970s, which returned approximately 380 kilograms (838 lb) of lunar rock and soil to Earth, as well as several missions of the Soviet Luna programme.

Atmosphere:

Much like Mercury, the Moon has a tenuous atmosphere (known as an exosphere), which results in severe temperature variations. These range from -153°C to 107°C on average, though temperatures as low as -249°C have been recorded. Measurements from NASA’s LADEE have mission determined the exosphere is mostly made up of helium, neon and argon.

The helium and neon are the result of solar wind while the argon comes from the natural, radioactive decay of potassium in the Moon’s interior. There is also evidence of frozen water existing in permanently shadowed craters, and potentially below the soil itself. The water may have been blown in by the solar wind or deposited by comets.

Formation:

Several theories have been proposed for the formation of the Moon. These include the fission of the Moon from the Earth’s crust through centrifugal force, the Moon being a preformed object that was captured by Earth’s gravity, and the Earth and Moon co-forming together in the primordial accretion disk. The estimated age of the Moon also ranges from it being formed 4.40-4.45 billion years ago to 4.527 ± 0.010 billion years ago,roughly 30–50 million years after the formation of the Solar System.

The prevailing hypothesis today is that the Earth-Moon system formed as a result of an impact between the newly-formed proto-Earth and a Mars-sized object (named Theia) roughly 4.5 billion years ago. This impact would have blasted material from both objects into orbit, where it eventually accreted to form the Moon.

This has become the most accepted hypothesis for several reasons. For one, such impacts were common in the early Solar System, and computer simulations modelling the impact are consistent with the measurements of the Earth-Moon system’s angular momentum, as well as the small size of the lunar core.

In addition, examinations of various meteorites show that other inner Solar System bodies (such as Mars and Vesta) have very different oxygen and tungsten isotopic compositions to Earth. In contrast, examinations of the lunar rocks brought back by the Apollo missions show that Earth and the Moon have nearly identical isotopic compositions.

This is the most compelling evidence suggesting that the Earth and the Moon have a common origin.

Relationship to Earth:

The Moon makes a complete orbit around Earth with respect to the fixed stars about once every 27.3 days (its sidereal period). However, because Earth is moving in its orbit around the Sun at the same time, it takes slightly longer for the Moon to show the same phase to Earth, which is about 29.5 days (its synodic period). The presence of the Moon in orbit influences conditions here on Earth in a number of ways.

The most immediate and obvious are the ways its gravity pulls on Earth – aka. it’s tidal effects. The result of this is an elevated sea level, which are commonly referred to as ocean tides. Because Earth spins about 27 times faster than the Moon moves around it, the bulges are dragged along with Earth’s surface faster than the Moon moves, rotating around Earth once a day as it spins on its axis.

The ocean tides are magnified by other effects, such as frictional coupling of water to Earth’s rotation through the ocean floors, the inertia of water’s movement, ocean basins that get shallower near land, and oscillations between different ocean basins. The gravitational attraction of the Sun on Earth’s oceans is almost half that of the Moon, and their gravitational interplay is responsible for spring and neap tides.

Gravitational coupling between the Moon and the bulge nearest the Moon acts as a torque on Earth’s rotation, draining angular momentum and rotational kinetic energy from Earth’s spin. In turn, angular momentum is added to the Moon’s orbit, accelerating it, which lifts the Moon into a higher orbit with a longer period.

As a result of this, the distance between Earth and Moon is increasing, and Earth’s spin is slowing down. Measurements from lunar ranging experiments with laser reflectors (which were left behind during the Apollo missions) have found that the Moon’s distance to Earth increases by 38 mm (1.5 in) per year.

This speeding and slowing of Earth and the Moon’s rotation will eventually result in a mutual tidal locking between the Earth and Moon, similar to what Pluto and Charon experience. However, such a scenario is likely to take billions of years, and the Sun is expected to have become a red giant and engulf Earth long before that.

The lunar surface also experiences tides of around 10 cm (4 in) amplitude over 27 days, with two components: a fixed one due to Earth (because they are in synchronous rotation) and a varying component from the Sun. The cumulative stress caused by these tidal forces produces moonquakes. Despite being less common and weaker than earthquakes, moonquakes can last longer (one hour) since there is no water to damp out the vibrations.

Another way the Moon effects life on Earth is through occultation (i.e. eclipses). These only happen when the Sun, the Moon, and Earth are in a straight line, and take one of two forms – a lunar eclipse and a solar eclipse. A lunar eclipse occurs when a full Moon passes behind Earth’s shadow (umbra) relative to the Sun, which causes it to darken and take on a reddish appearance (aka. a “Blood Moon” or “Sanguine Moon”.)

A solar eclipse occurs during a new Moon, when the Moon is between the Sun and Earth. Since they are the same apparent size in the sky, the moon can either partially block the Sun (annular eclipse) or fully block it (total eclipse). In the case of a total eclipse, the Moon completely covers the disc of the Sun and the solar corona becomes visible to the naked eye.

*The geometry that creates a total lunar eclipse. Credit: NASA*

Because the Moon’s orbit around Earth is inclined by about 5° to the orbit of Earth around the Sun, eclipses do not occur at every full and new moon. For an eclipse to occur, the Moon must be near the intersection of the two orbital planes.The periodicity and recurrence of eclipses of the Sun by the Moon, and of the Moon by Earth, is described by the “Saros Cycle“, which is a period of approximately 18 years.

History of Observation:

Human beings have been observing the Moon since prehistoric times, and understanding the Moon’s cycles was one of the earliest developments in astronomy. The earliest examples of this comes from the 5th century BCE, when Babylonian astronomers had recorded the 18-year Satros cycle of lunar eclipses, and Indian astronomers had described the Moon’s monthly elongation.

The ancient Greek philosopher Anaxagoras (ca. 510 – 428 BCE) reasoned that the Sun and Moon were both giant spherical rocks, and the latter reflected the light of the former. In Aristotle’s “On the Heavens“, which he wrote in 350 BCE, the Moon was said to mark the boundary between the spheres of the mutable elements (earth, water, air and fire), and the heavenly stars – an influential philosophy that would dominate for centuries.

In the 2nd century BCE, Seleucus of Seleucia correctly theorized that tides were due to the attraction of the Moon, and that their height depends on the Moon’s position relative to the Sun. In the same century, Aristarchus computed the size and distance of the Moon from Earth, obtaining a value of about twenty times the radius of Earth for the distance. These figures were greatly improved by Ptolemy (90–168 BCE), who’s values of a mean distance of 59 times Earth’s radius and a diameter of 0.292 Earth diameters were close to the correct values (60 and 0.273 respectively).

By the 4th century BCE, the Chinese astronomer Shi Shen gave instructions for predicting solar and lunar eclipses. By the time of the Han Dynasty (206 BCE – 220 CE), astronomers recognized that moonlight was reflected from the Sun, and Jin Fang (78–37 BC) postulated that the Moon was spherical in shape.

In 499 CE, the Indian astronomer Aryabhata mentioned in his Aryabhatiya that reflected sunlight is the cause of the shining of the Moon. The astronomer and physicist Alhazen (965–1039) found that sunlight was not reflected from the Moon like a mirror, but that light was emitted from every part of the Moon in all directions.

Shen Kuo (1031–1095) of the Song dynasty created an allegory to explain the waxing and waning phases of the Moon. According to Shen, it was comparable to a round ball of reflective silver that, when doused with white powder and viewed from the side, would appear to be a crescent.

During the Middle Ages, before the invention of the telescope, the Moon was increasingly recognized as a sphere, though many believed that it was “perfectly smooth”. In keeping with medieval astronomy, which combined Aristotle’s theories of the universe with Christian dogma, this view would later be challenged as part of the Scientific Revolution (during the 16th and 17th century) where the Moon and other planets would come to be seen as being similar to Earth.

Using a telescope of his own design, Galileo Galilei drew one of the first telescopic drawings of the Moon in 1609, which he included in his book Sidereus Nuncius (“Starry Messenger). From his observations, he noted that the Moon was not smooth, but had mountains and craters. These observations, coupled with observations of moons orbiting Jupiter, helped him to advance the heliocentric model of the universe.

Telescopic mapping of the Moon followed, which led to the lunar features being mapped in detail and named. The names assigned by Italian astronomers Giovannia Battista Riccioli and Francesco Maria Grimaldi are still in use today. The lunar map and book on lunar features created by German astronomers Wilhelm Beer and Johann Heinrich Mädler between 1834 and 1837 were the first accurate trigonometric study of lunar features, and included the heights of more than a thousand mountains.

Lunar craters, first noted by Galileo, were thought to be volcanic until the 1870s, when English astronomer Richard Proctor proposed that they were formed by collisions. This view gained support throughout the remainder of the 19th century; and by the early 20th century, led to the development of lunar stratigraphy – part of the growing field of astrogeology.

Exploration:

With the beginning of the Space Age in the mid-20th century, the ability to physically explore the Moon became possible for the first time. And with the onset of the Cold War, both the Soviet and American space programs became locked in an ongoing effort to reach the Moon first. This initially consisted of sending probes on flybys and landers to the surface, and culminated with astronauts making manned missions.

*The Soviet Luna 1 Robotic space probe. Credit: RIA Novosti/ Alexander Mokletsov/Public Domain*

Exploration of the Moon began in earnest with the Soviet Luna program. Beginning in earnest in 1958, the programmed suffered the loss of three unmanned probes. But by 1959, the Soviets managed to successfully dispatch fifteen robotic spacecraft to the Moon and accomplished many firsts in space exploration. This included the first human-made objects to escape Earth’s gravity (Luna 1), the first human-made object to impact the lunar surface (Luna 2), and the first photographs of the far side of the Moon (Luna 3).

Between 1959 and 1979, the program also managed to make the first successful soft landing on the Moon (Luna 9), and the first unmanned vehicle to orbit the Moon (Luna 10) – both in 1966. Rock and soil samples were brought back to Earth by three Luna sample return missions – Luna 16 (1970), Luna 20 (1972), and Luna 24 (1976).

Two pioneering robotic rovers landed on the Moon – Luna 17 (1970) and Luna 21 (1973) – as a part of Soviet Lunokhod program. Running from 1969 to 1977, this program was primarily designed to provide support for the planned Soviet manned moon missions. But with the cancellation of the Soviet manned moon program, they were instead used as remote-controlled robots to photograph and explore the lunar surface.

NASA began launching probes to provide information and support for an eventual Moon landing in the early 60s. This took the form of the Ranger program, which ran from 1961 – 1965 and produced the first close-up pictures of the lunar landscape. It was followed by the Lunar Orbiter program which produced maps of the entire Moon between 1966-67, and the Surveyor program which sent robotic landers to the surface between 1966-68.

In 1969, astronaut Neil Armstrong made history by becoming the first person to walk on the Moon. As the commander of the American mission Apollo 11, he first sett foot on the Moon at 02:56 UTC on 21 July 1969. This represented the culmination of the Apollo program (1969-1972), which sought to send astronauts to the lunar surface to conduct research and be the first human beings to set foot on a celestial body other than Earth.

The Apollo 11 to 17 missions (save for Apollo 13, which aborted its planned lunar landing) sent a total of 13 astronauts to the lunar surface and returned 380.05 kilograms (837.87 lb) of lunar rock and soil. Scientific instrument packages were also installed on the lunar surface during all the Apollo landings. Long-lived instrument stations, including heat flow probes, seismometers, and magnetometers, were installed at the Apollo 12, 14, 15, 16, and 17 landing sites, some of which are still operational.

After the Moon Race was over, there was a lull in lunar missions. However, by the 1990s, many more countries became involve in space exploration. In 1990, Japan became the third country to place a spacecraft into lunar orbit with its Hiten spacecraft, an orbiter which released the smaller Hagoroma probe.

In 1994, the U.S. sent the joint Defense Department/NASA spacecraft Clementine to lunar orbit to obtain the first near-global topographic map of the Moon and the first global multispectral images of the lunar surface. This was followed in 1998 by the Lunar Prospector mission, whose instruments indicated the presence of excess hydrogen at the lunar poles, which is likely to have been caused by the presence of water ice in the upper few meters of the regolith within permanently shadowed craters.

Mosaic of the Chang'e-3 moon lander and the lunar surface taken by the camera on China’s Yutu moon rover from a position south of the lander during Lunar Day 3. Note the landing ramp and rover tracks at left. Credit: CNSA/SASTIND/Xinhua/Marco Di Lorenzo/Ken Kremer — *Mosaic of the Chang’e-3 moon lander and the lunar surface, taken by the Yutu rover during Lunar Day 3. Credit: CNSA/SASTIND/Xinhua/Marco Di Lorenzo/Ken Kremer*

Since the year 2000, exploration of the moon has intensified, with a growing number of parties becoming involved. The ESA’s SMART-1 spacecraft, the second ion-propelled spacecraft ever created, made the first detailed survey of chemical elements on the lunar surface while in orbit from November 15th, 2004, until its lunar impact on September 3rd, 2006.

China has pursued an ambitious program of lunar exploration under their Chang’e program. This began with Chang’e 1, which successfully obtained a full image map of the Moon during its sixteen month orbit (November 5th, 2007 – March 1st, 2009) of the Moon. This was followed in October of 2010 with the Chang’e 2 spacecraft, which mapped the Moon at a higher resolution before performing a flyby of asteroid 4179 Toutatis in December of 2012, then heading off into deep space.

On 14 December 2013, Chang’e 3 improved upon its orbital mission predecessors by landing a lunar lander onto the Moon’s surface, which in turn deployed a lunar rover named Yutu (literally “Jade Rabbit”). In so doing, Chang’e 3 made the first soft lunar landing since Luna 24 in 1976, and the first lunar rover mission since Lunokhod 2 in 1973.

Between October 4th, 2007, and June 10th, 2009, the Japan Aerospace Exploration Agency‘s (JAXA) Kaguya (“Selene”) mission – a lunar orbiter fitted with a high-definition video camera and two small radio-transmitter satellites – obtained lunar geophysics data and took the first high-definition movies from beyond Earth orbit.

The Indian Space Research Organisation (ISRO) first lunar mission, Chandrayaan I, orbited the Moon between November 2008 and August 2009 and created a high resolution chemical, mineralogical and photo-geological map of the lunar surface, as well as confirming the presence of water molecules in lunar soil. A second mission was planned for 2013 in collaboration with Roscosmos, but was cancelled.

NASA has also been busy in the new millennium. In 2009, they co-launched the Lunar Reconnaissance Orbiter (LRO) and the Lunar CRater Observation and Sensing Satellite (LCROSS) impactor. LCROSS completed its mission by making a widely observed impact in the crater Cabeus on October 9th, 2009, while the LRO is currently obtaining precise lunar altimetry and high-resolution imagery.

Two NASA Gravity Recovery And Interior Library (GRAIL) spacecraft began orbiting the Moon in January 2012 as part of a mission to learn more about the Moon’s internal structure.

Upcoming lunar missions include Russia’s Luna-Glob – an unmanned lander with a set of seismometers, and an orbiter based on its failed Martian Fobos-Grunt mission. Privately funded lunar exploration has also been promoted by the Google Lunar X Prize, which was announced on September 13th, 2007, and offers US$20 million to anyone who can land a robotic rover on the Moon and meet other specified criteria.

Under the terms of the Outer Space Treaty, the Moon remains free to all nations to explore for peaceful purposes. As our efforts to explore space continue, plans to create a lunar base and possibly even a permanent settlement may become a reality. Looking to the distant future, it wouldn’t be far fetched at all to imagine native-born humans living on the Moon, perhaps known as Lunarians (though I imagine Lunies will be more popular!)

We have many interesting articles about the Moon here at Universe Today. Below is a list that covers just about everything we know about it today. We hope you find what you are looking for:

September 17, 2015December 23, 2015 by Ken Kremer

First Manned Flight of NASA’s Orion Deep Space Capsule Could Slip to 2023

NASA Orion spacecraft blasts off atop 1st Space Launch System rocket in 2017 - attached to European provided service module – on an enhanced m mission to Deep Space where an asteroid could be relocated as early as 2021. Credit: NASA

The first manned flight of NASA’s Orion deep space capsule – currently under development – could slip two years from 2021 to 2023 due to a variety of budget and technical issues, top NASA officials announced on Wednesday, Sept. 16.

The potential two year postponement of Orion’s first flight with astronauts follows on the heels of the agency’s recently completed rigorous review of the programs status from a budgetary, technical, engineering, safety and risk assessment analysis of the vehicles systems and subsystems.

But Orion’s launch delay has already been condemned by some in Congress who accuse the Obama Administration of purposely shortchanging funding for the program.

Based on the budget available and all the work remaining to be accomplished, liftoff of the first Orion test flight with an astronaut crew is likely to occur “no later than April 2023,” said NASA Associate Administrator Robert Lightfoot at the Sept. 16 briefing for reporters.

NASA had been marching towards an August 2021 liftoff for the maiden crewed Orion on a test flight dubbed Exploration Mission-2 (EM-2), until Lightfoot’s announcement.

Lightfoot added that although August 2021 is still NASA’s officially targeted launch date for EM-2, achieving that early goal is not likely as a direct result of the program review.

“The team is still working toward a launch in August 2021, but have much less confidence in achieving that. But we are not changing that date for EM-2 at this time.”

“But we’re committing that we’ll be no later than April 2023.”

“It’s not a very high confidence level [on making the August 2021 launch date], I’ll tell you that, just because of the things we see historically pop up.”

Orion is being developed by NASA to send America’s astronauts on journeys venturing farther into deep space than ever before – back to the Moon first and then beyond to Asteroids, Mars and other destinations in our Solar System.

Artist's conception of NASA's Space Launch System with Orion crewed deep space capsule. Credit: NASA — Artist’s conception of NASA’s Space Launch System with Orion crewed deep space capsule. Credit: NASA

Orion’s likely launch slip is the direct fallout from NASA’s recently completed internal program review called Key Decision Point C (KDP-C).

The KDC-P review assesses all the technological work and advancements required for launch to design, develop and manufacture Orion and that can be accomplished based on the Federal budget that will be available to carry out the program successfully.

“The KDC-P analysis just completed and decision to move forward with the Orion program is based on a 70% confidence level of success,” notes Lightfoot.

“The budget is a factor in the timing for the projection. It is based on the President’s current budget.”

“The decision commits NASA to a development cost baseline of $6.77 billion from October 2015 through the first crewed mission (EM-2) and a commitment to be ready for a launch with astronauts no later than April 2023.”

“EM-2 is a full up Orion on a human mission,” he said.

The EM-2 mission would last about 3 weeks and fly in a lunar retrograde orbit. It would carry astronauts beyond the Moon and further out into space than ever before.

Prior to EM-2, Orion’s next test flight is the uncrewed EM-1 mission targeted to launch no later than November 2018 – from Launch Complex 39-B at the Kennedy Space Center.

EM-1 will blastoff on the inaugural launch of NASA’s mammoth Space Launch System (SLS) heavy lift booster concurrently under development. The SLS will be configured in its initial 70-metric-ton (77-ton) version with a liftoff thrust of 8.4 million pounds. It will boost an unmanned Orion on an approximately three week long test flight beyond the Moon and back.

Toward that goal, NASA is also currently testing the RS-25 first stage engines that will power SLS – as outlined in my recent story here.

Orion’s inaugural mission dubbed Exploration Flight Test-1 (EFT) was successfully launched on a flawless flight on Dec. 5, 2014 atop a United Launch Alliance Delta IV Heavy rocket Space Launch Complex 37 (SLC-37) at Cape Canaveral Air Force Station in Florida.

Orion learned a lot from EFT-1 and the lessons learned are being incorporated into the EM-1 and EM-2 missions.

Among the very few changes is an alteration in the heat shield from a monolithic to a block design that will vastly simplify its manufacture.

“We are making the heat shield change as a result of what we leaned on EFT-1,” said William Gerstenmaier, the agency’s associate administrator for Human Exploration and Operations at NASA Headquarters, at the briefing.

“The Orion Program has done incredible work, progressing every day and meeting milestones to prepare for our next missions. The team will keep working toward an earlier readiness date for a first crewed flight, but will be ready no later than April 2023, and we will keep the spacecraft, rocket and ground systems moving at their own best possible paces.”

Some members of Congress and others have said that delays in the Orion and SLS program are also a direct result of funding shortfalls caused by budget cuts in the programs, and condemned the Obama Administrations 2016 NASA budget request.

In fact, the Obama Administration did request $440 million less in the 2016 NASA budget request vs. the 2015 request.

“Once again, the Obama administration is choosing to delay deep space exploration priorities such as Orion and the Space Launch System that will take U.S. astronauts to the Moon, Mars, and beyond, said Rep Lamar Smith (R-Texas) House Committee Chairman of the House Science, Space, and Technology Committee.

“While this administration has consistently cut funding for these programs and delayed their development, Congress has consistently restored funding as part of our commitment to maintaining American leadership in space,” said Chairman Smith.

“We must chart a compelling course for our nation’s space program so that we can continue to inspire future generations of scientists, engineers and explorers. I urge this administration to follow the lead of the House Science, Space, and Technology Committee’s NASA Authorization Act to fully fund NASA’s exploration programs.”

Smith added that he “has repeatedly criticized the Obama administration for failure to request adequate funding for Orion and the Space Launch System; the administration’s FY16 budget request proposed cuts of more than $440 million for the programs.”

“The House Science Committee’s NASA Authorization Act for 2016 and 2017 sought to restore $440 million to these crucial programs being developed to return U.S. astronauts to deep space destinations such as the Moon and Mars. That bill also restored funding for planetary science accounts that have been responsible for missions such as the recent Pluto fly-by, and provided full funding for the other space exploration programs such as Commercial Crew and Commercial Cargo programs.”

Stay tuned here for Ken’s continuing Earth and planetary science and human spaceflight news.

Ken Kremer

September 15, 2015December 23, 2015 by David Dickinson

A Minor Lunar Standstill for 2015

Think you know the Moon? Whether you love our natural neighbor in space for the lunar and solar eclipses it provides, or you simply decide to ‘pack it in’ from deep sky observing on the weeks bookending Full phase — per chance to catch up on image processing — the Moon has provided humanity with a fine crash course in Celestial Mechanics 101.

Take the Moon’s path in the Fall of 2015 as a peculiar case in point. In fact, we’re nearing what’s known as a minor lunar standstill over the next lunation, the first of the 21^st century.

The term lunar standstill is kind of a misnomer. The Moon will continue in its orbit around the Earth like it always does. What’s interesting to note, however, is how shallow the apparent path of the Moon currently is with respect to the ecliptic this year. A technical lunar standstill – the point at which the Moon seems to reverse course from north to south and vice versa – occurs twice a lunation… but not all lunar standstills are created equal.

The path of the ecliptic vs the orbit of the Moon on ‘shallow’ and ‘steep’ years. Image credit: Dave Dickinson

The approximately five degree tilt of the Moon’s path around the Earth with respect to the path of the Earth around the Sun assures that the Moon can actually appear anywhere from 23.5 degrees (the tilt of the Earth’s axis with respect to the ecliptic) plus five degrees above or below the celestial equator, or 28.5 degrees declination north to south.

Such a ‘hilly year’ happens once every 18.6 years, and last occurred in 2006, and won’t take place again until 2025. This orbital phenomenon also results in what’s known as a ‘long nights moon’ when the Full Moon nearest the winter solstice rides high in the sky near the spot the summer Sun occupied six months earlier, and will do so again six months hence.

To quote Game of Thrones: “Winter is coming,” indeed.

Such is the wacky orbit of the Moon. Unlike the majority of natural satellites in the solar system, the inclination of the Moon’s orbit is not fixed in relation to its host planet’s (in this case, the Earth’s) equator, but instead, to the plane of its path around the Sun, that imaginary line known as the ecliptic. Hence, we say the Moon’s path is either steep and ‘hilly’ near a major lunar standstill, or shallow and almost flat-lined, like this year. In between years are sometimes termed ‘ecliptic-like’ and happen between standstills once every 9.3 years.

Why are the nodes of the ecliptic changing? The chief culprit is the gravitational pull of the Sun, which drags the nodes opposite in the Moon’s direction of travel once around full circle every 18.6 years. To confound things even more, the Moon’s line of apsides (the imaginary line bisecting its orbit from apogee to perigee) is moving in the opposite direction and completes one revolution every 8.85 years.

This also means that the Moon can wander off the beaten trail of the zodiac constellations well worn by the classical planets. The Moon can actually transit 18 constellations: the 12 familiar zodiacal constellations, plus Orion, Ophiuchus, Sextans, Corvus, Auriga and Cetus.

This, along with the 26,000 plus year precession of the equinoxes, also means that the stars the Moon can occult along its path are slowly changing as well.

There’s lots of evidence to suggest that ancient astronomers knew something of the cycle of lunar standstills as well. The modern term comes from archaeologist Alexander Thom’s 1971 book Megalithic Lunar Observatories. There is evidence to suggest Bronze Age cultures in the United Kingdom took note of the changing path of the Moon. The famous ‘Sun dagger’ rock alignment of Fajada Butte in Chaco Canyon, New Mexico may have also doubled as a similar sort of calendar that not only marked the yearly solstices and equinoxes, but longer periods of the cycles of the Moon as well.

Knowing the gear clock tick of the heavens gave cultures an edge, allowing them to predict when to sow, reap, hunt and prepare for the onset of winter.

The 2015 minor lunar standstill also impacts this years’ Full Harvest Moon as well. Ordinarily on most years, the evening angle of the ecliptic versus the eastern horizon near the autumnal equinox conspires to make the Moon seem to ‘freeze’ in its nightly path, rising scant minutes later on successive evenings. This effect is most dramatic as seen from mid-northern latitudes in September on years around the major lunar standstill.

Not so in 2015. The Full Harvest Moon occurs on September 28^th at 2:50 UT (10:50 PM EDT on the evening of the 27^th) about four and half days after the autumnal equinox. As seen from latitude 40 degrees north, however, the Moon will rise nearly 40 minutes later each successive evening. Check out these Moonrise times as seen from the U.S. capital near 39 degrees north latitude:

Washington D.C.

Sept 25^th 5:28 PM

Sept 26^th 6:09 PM

Sept 27^th 6:49 PM

Sept 28^th: 7:29 PM

Sept 29^th: 8:11 PM

As you can see, the minor lunar standstill of 2015 ameliorates the usual impact of the Harvest Moon… though we do have the final total lunar eclipse of 2015 to compensate.

New Horizons Team Delves into the Mystery of Charon’s “Red Pole”

Details of Pluto’s largest moon, Charon, are revealed in this image from New Horizons’ Long Range Reconnaissance Imager (LORRI), taken July 13, 2015, from a distance of 289,000 miles (466,000 kilometers), combined with color information obtained by New Horizons’ Ralph instrument on the same day. The distinctive red marking in Charon’s north polar region is currently being studied by scientists. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute)

As we await new imagery and data from the New Horizons’ flyby of the Pluto system to be transmitted to Earth, one piece of the Pluto-Charon puzzle that scientists are looking forward learning more about is the mysterious “dark pole” on Charon. Images sent immediately after the flyby reveal Charon’s north polar region is much darker than the lighter-colored material surrounding it, and it actually has a reddish cast to it.

The New Horizons team says the red pole appears to be a thin deposit of dark material over a distinct, sharply bounded, angular feature – perhaps and impact basin – and scientists hope to learn more by studying higher-resolution images that are currently being beamed back to Earth from the spacecraft.

Carly Howett, a senior research scientist at the Southwest Research Institute, is one of the scientists studying the mystery of what is causing this color difference and why it shows up at Charon’s north pole.

“Looking at Charon, it’s very clear that the northern polar region is much redder than the rest of the moon,” said Howett in a post on the New Horizons website. “Surfaces vary in color when something about them changes.”

So what is this red material? The leading theory right now is that material from Pluto’s atmosphere is falling to Charon and being ensnared in the polar region by what is known as “cold-trapping.”

It’s is so cold at Charon’s poles – temperatures there vary are just a tad warmer than absolute zero, between -433 and -351 °F (-258 and -213 °C) – that any gases settling there would freeze solid instead of escaping. And with the combination of extremely cold temperatures and solar radiation, the material is transformed to a new substance, and is being trapped on the pole. Howett said it likely won’t disappear with any seasonal changes on Charon.

“We know Pluto’s atmosphere is mainly nitrogen, with some methane and carbon monoxide,” she said, “so we expect that these same constituents are slowly coating Charon’s winter pole. The frozen ices would sublimate away again as soon as Charon’s winter pole emerges back into sunlight, except for one important detail: solar radiation modifies these ices to produce a new substance, which has a higher sublimation temperature and can’t sublimate and then escape from Charon.”

What is the new substance? Scientists can’t say for sure yet, but it might be a tholin.

Scientists at Johns Hopkins University’s Hörst Laboratory have produced complex chemical compounds called tholins, which may give Pluto its reddish hue. (Image credit: Chao He, Xinting Yu, Sydney Riemer, and Sarah Hörst, Johns Hopkins University).

What is a tholin? Tholins were first created in a laboratory by in the 1970s by Carl Sagan and his team at Cornell. According to planetary scientist Sarah Hörst, who wrote about tholins on The Planetary Society website, Sagan and his team would take mixtures of cosmically relevant gases and irradiate them with various energy sources. The result was “a brown, sometimes sticky, residue,” as Sagan described them in a paper he wrote in 1979.

Hörst said Sagan and team “were searching for answers to questions ranging from ‘why is the Great Red Spot red’ to ‘how did life on Earth originate’ and in the process produced material for which there was no name.”

They came up with the name “tholin,” and theorized that tholins could be a constituent of the Earth’s primitive oceans and therefore as relevant to the origin of life.

In the article Hörst wrote, “I have been studying tholin for almost a decade and in my experience the most frequently used synonyms for tholin are “gunk”, “brown gunk”, and “complex organic gunk”. Tholin is also often described as a “tar-like” substance. Words like tar, kerogen, bitumen, petroleum, asphalt, etc. all describe substances that are potentially similar to tholin in some ways. However, these materials all result from life; they are’biotic.’”

Charon approach from New Horizons. Credit: NASA/Damian Peach

Finding out more about what is going on at Charon’s north pole is indeed intriguing. Tholins might be the same material that give Pluto its reddish-brown hue in some regions, too.

Howett told Universe Today that the main instrument on New Horizons that will really pin down the compositional information is LEISA (Linear Etalon Imaging Spectral Array).

“This instrument observes 250 wavelengths between 1.25-2.5 microns, making it ideal for detecting the spectral signature of solid features,” she said via email. “We don’t know exactly the composition of the tholin on Charon (many different types are possible) but with LEISA we can look for differences in the spectra between the Charon’s anomalous red region and those surrounding it – to give us some hints of the change in surface composition and the “raw ingredients” for the tholin.”

For example, Howett said, maybe they’ll see more hydrogen cyanide (HCN) around the north pole region, which would open up a lot of complex chemistry options.

“We will start getting this data down in the next few weeks, so hopefully we’ll have some answers soon!” she said.

Further reading: New Horizons website, The Planetary Society

September 5, 2015December 23, 2015 by Ken Kremer

Boeing ‘Starliner’ Crew Spaceship; America’s Next Ride to Space Takes Shape

First view of the Boeing CST-100 ‘Starliner’ crewed space taxi at the Sept. 4, 2015 Grand Opening ceremony held in the totally refurbished C3PF manufacturing facility at NASA’s Kennedy Space Center. These are the upper and lower segments of the first Starliner crew module known as the Structural Test Article (STA) being built at Boeing’s Commercial Crew and Cargo Processing Facility (C3PF) at KSC. Credit: Ken Kremer /kenkremer.com
Story/photos updated[/caption]

KENNEDY SPACE CENTER, FL – ‘Starliner’ is the new name of America’s next spaceship destined to launch our astronauts to orbit. The new commercial craft from Boeing will restore America’s capability to launch American astronauts from American soil to the International Space Station (ISS) in 2017 – and the magnificent looking first capsule is already taking shape!

Built by The Boeing Company, ‘Starliner’ was officially announced by Boeing and NASA as the new name of the company’s CST-100 commercial crew transportation spacecraft during the Grand Opening event for the craft’s manufacturing facility held at the Kennedy Space Center on Friday, Sept 4. 2015 and attended by Universe Today.

‘Starliner’ counts as history’s first privately developed ‘Space Taxi’ to carry humans to space – along with the Crew Dragon being simultaneously developed by SpaceX.

“Please welcome the CST-100 Starliner,” announced Chris Ferguson, the former shuttle commander who now is deputy manager of operations for Boeing’s Commercial Crew Program, at the Grand Opening event hosting numerous dignitaries.

The CST-100 ‘Starliner’ is at the forefront of ushering in the new commercial era of space flight and will completely revolutionize how we access, explore and exploit space for the benefit of all mankind.

Starliner will be mostly automated for ease of operation and is capable of transporting astronaut crews of four or more to low Earth orbit and the ISS as soon as mid 2017 if all goes well and Congress approves the required funding.

“One hundred years ago we were on the dawn of the commercial aviation era and today, with the help of NASA, we’re on the dawn of a new commercial space era,” said Boeing’s John Elbon, vice president and general manager of Space Exploration.

“It’s been such a pleasure to work hand-in-hand with NASA on this commercial crew development, and when we look back 100 years from this point, I’m really excited about what we will have discovered.”

Boeing ‘Starliner’ commercial crew space taxi manufacturing facility marks Grand Opening at the Kennedy Space Center on Sept 4. 2015. Exterior view depicting newly installed mural for the Boeing Company’s newly named CST-100 ‘Starliner’ commercial crew transportation spacecraft on the company’s Commercial Crew and Cargo Processing Facility (C3PF) at NASA’s Kennedy Space Center in Florida. Credit: Ken Kremer /kenkremer.com

The CST-100 ‘Starliner’ will be produced in Boeing’s newly revamped manufacturing facility dubbed the Commercial Crew and Cargo Processing Facility (C3PF) on site at the Kennedy Space Center in Florida.

The CC3P building was previously known as Orbiter Processing Facility-2 (OPF-3) and utilized by NASA to process the agency’s space shuttle orbiters between crewed flights during the three decade long Space Shuttle program.

“When Boeing was looking for the prime location for its program headquarters, we knew Florida had a lot to offer from the infrastructure to the supplier base to the skilled work force,” said Chris Ferguson.

“Starliner will launch on an Atlas V from pad 41 at Cape Canaveral Air Force Station in Florida. It has the capability to dock at the ISS within 24 hours. It can stay docked at the station for 6 months.”

Over the past few years, the historic facility has been completely renovated, upgraded and transformed into a state of the art manufacturing site for Boeing’s commercial CST-100 Starliner.

First view of upper half of the Boeing CST-100 '?Starliner?' crewed space taxi unveiled at the Sept. 4, 2015 Grand Opening ceremony held in the totally refurbished C3PF manufacturing facility at NASA's Kennedy Space Center. This will be part of the first Starliner crew module known as the Structural Test Article (STA) being built at Boeing’s Commercial Crew and Cargo Processing Facility (C3PF) at KSC. Credit: Ken Kremer /kenkremer.com — First view of upper half of the Boeing CST-100 ‘Starliner’ crewed space taxi unveiled at the Sept. 4, 2015 Grand Opening ceremony held in the totally refurbished C3PF manufacturing facility at NASA’s Kennedy Space Center. This will be part of the first Starliner crew module known as the Structural Test Article (STA) being built at Boeing’s Commercial Crew and Cargo Processing Facility (C3PF) at KSC. Credit: Ken Kremer /kenkremer.com

Boeing was awarded a $4.2 Billion contract in September 2014 by NASA Administrator Charles Bolden to complete development and manufacture of the CST-100 space taxi under the agency’s Commercial Crew Transportation Capability (CCtCap) program and NASA’s Launch America initiative.

It is also a key part of NASA’s overarching strategy to send Humans on a “Journey to Mars” in the 2030s.

“Commercial crew is an essential component of our journey to Mars, and in 35 states, 350 American companies are working to make it possible for the greatest country on Earth to once again launch our own astronauts into space,” said NASA Administrator Charles Bolden. “That’s some impressive investment.”

Crew access tunnel and seal for Boeing CST-100 Starliner that attaches to upper dome of the crew module for the Structural Test Article being manufactured at the company’s Commercial Crew and Cargo Processing Facility (C3PF) at NASA’s Kennedy Space Center in Florida. Credit: Ken Kremer /kenkremer.com — Crew access tunnel and hatch for Boeing CST-100 Starliner that attaches to upper dome of the crew module for the Structural Test Article being manufactured at the company’s Commercial Crew and Cargo Processing Facility (C3PF) at NASA’s Kennedy Space Center in Florida. Credit: Ken Kremer /kenkremer.com

The commercial crew program is designed to return human spaceflight launches to the United States and end our sole source reliance on Russia and the Soyuz capsule for all manned flights to the ISS and crew rotation missions.

Since the forced retirement of NASA’s shuttle orbiters in 2011, US astronauts have been totally dependent on the Russians for trips to space and back.

SpaceX also received a NASA award worth $2.6 Billion to build the Crew Dragon spacecraft for launch atop the firms man-rated Falcon 9 rocket.

Final assembly of both half’s of Starliner will take place in the C3PF – namely the crew command module and the service module.

Boeing is already building the first version of Starliner known as the Structural Test Article (STA) . The STA will be used for extensive prelaunch testing and evaluation to ensure it will be ready and robust and capable of safely launches humans to orbit on a very cost effective basis.

The Starliner STA is rapidly taking shape. The first components have been built and were on display at the C3PF Grand Opening eventy of Sept. 4. They are comprised of the upper and lower halves of the crew command module, the crew access tunnel and adapter.

The shell of Starliner’s first service module was also on display.

“The STA will be completed in early 2016,” said John Mulholland Boeing Vice President, Commercial Programs, at the event.

“Then we start assembly of the Qualification Test Article.”

I asked Mulholland to describe the currently planned sequence of Starliner’s initial uncrewed and crewed flights.

“The first uncrewed flight is expected to occur in May 2017. Then comes the Pad Abort Test in August 2017. The first crewed flight is set for September 2017. The first contracted regular service flight (PCM-1) is set for December 2017,” Mulholland told me.

“It’s all very exciting.”

Boeing CST-100 crew capsule will carry five person crews to the ISS. Credit: Ken Kremer - kenkremer.com — Boeing CST-100 crew capsule will carry five person crews to the ISS. Credit: Ken Kremer – kenkremer.com

“Kennedy Space Center has transitioned more than 50 facilities for commercial use. We have made improvements and upgrades to well-known Kennedy workhorses such as the Vehicle Assembly Building, mobile launcher, crawler–transporter and Launch Pad 39B in support of Orion, the SLS and Advanced Exploration Systems,” said Robert Cabana, Kennedy’s center director.

“I am proud of our success in transforming Kennedy Space Center to a 21st century, multi-user spaceport that is now capable of supporting the launch of all sizes and classes of vehicles, including horizontal launches from the Shuttle Landing Facility, and spacecraft processing and landing.”

Boeing and NASA managers pose with the Boeing CST-100 Starliner crew module being assembled into the Structural Test Article at company’s C3PF facility at the Kennedy Space Center in Florida. From left are John Mulholland, Boeing Vice President Commercial Programs; Chris Ferguson, former shuttle commander now Boeing deputy manager Commercial Crew Program; John Elbon, Boeing vice president and general manager of Space Exploration; and Robert Cabana, former shuttle commander and now Director NASA’s Kennedy Space Center, on Sept. 4, 2015. Credit: Ken Kremer/kenkremer.com

Read my earlier exclusive, in depth one-on-one interviews with Chris Ferguson – America’s last shuttle commander and who now leads Boeings CST-100 program; here and here.

Stay tuned here for Ken’s continuing Earth and planetary science and human spaceflight news.

Ken Kremer

Boeing’s commercial CST-100 'Space Taxi' will carry a crew of five astronauts to low Earth orbit and the ISS from US soil. Mockup with astronaut mannequins seated below pilot console and Samsung tablets was unveiled on June 9, 2014 at its planned manufacturing facility at the Kennedy Space Center in Florida. Credit: Ken Kremer - kenkremer.com — Boeing’s commercial CST-100 ‘Space Taxi’ will carry a crew of five astronauts to low Earth orbit and the ISS from US soil. Mockup with astronaut mannequins seated below pilot console and Samsung tablets was unveiled on June 9, 2014 at its planned manufacturing facility at the Kennedy Space Center in Florida. Credit: Ken Kremer – kenkremer.com

September 1, 2015December 23, 2015 by David Dickinson

Watch the Moon Occult Aldebaran This Weekend

How about that perigee Full Moon this past weekend? Thus begins ‘Supermoon season’ for 2015, as this month’s Full Moon occurs even closer to perigee — less than an hour apart, in fact — on September 28^th, with the final total lunar eclipse of the ongoing tetrad to boot. Keep an eye on Luna this week, as it crosses into the early AM sky for several key dates with destiny just prior to the start of the second and final eclipse season for 2015.

The big event later this week is a passage of the waning gibbous Moon through the Hyades open cluster on the morning of Saturday, September 5^th, climaxing with a dramatic occultation of the bright star Aldebaran on the same morning. This is part of a series of 49 ongoing occultations of Aldebaran by the Moon, one for each lunation extending out to September 2018.

This weekend’s event will occur at moonrise under nighttime skies for the northeastern United States and the Canadian Maritimes, and near dawn and under daytime skies for observers in Western Europe and Northern Africa eastward. We observed an occultation of Aldebaran by the Moon under daytime skies from Alaska back in the late 1990s, and can attest that the star is indeed visible near the limb of the Moon in binoculars. A good deep blue sky is key to spotting +1 magnitude Aldebaran in the daytime.

London 711 AM — The view from London UK at 7:11 AM local. Image Credit: Starry Night Education software

During waning phase, the bright edge of the Moon is always leading, meaning Aldebaran will ingress (wink out) on the bright limb of the 52% illuminated Moon, and egress (reappear) along its dark limb.

Here are some key times for ingress/egress by location (all times quoted are local and incorporate daylight saving/summer time):

Washington D.C.

Moonrise: 11:53 PM

Ingress: N/A (before Moonrise)

Egress: 12:38 AM (altitude = 8 degrees)

Boston

Moonrise: 11:22 PM

Ingress 11:57 PM (altitude = 6 degrees)

Egress: 12:41 AM (altitude = 14 degrees)

Gander, Newfoundland

Moonrise: 11:26 PM

Ingress: 1:37 AM (altitude = 20 degrees)

Egress: 2:26 AM (altitude = 28 degrees)

London

Moonrise: 11:04 PM

Ingress: 5:50 AM (altitude = 53 degrees)

Sunrise: 6:18 AM

Egress: 7:07 AM (altitude = 54 degrees)

Paris

Moonrise: 12:02 AM

Ingress: 6:53 AM (altitude = 56 degrees)

Sunrise: 7:12 AM

Egress: 8:10 AM (altitude = 57 degrees)

Occultations of bright stars by the Moon are one of the few times besides a solar or lunar eclipse when you can actually discern the one degree per every two and half hours orbital motion of the Moon in real time. The Moon moves just a little more than its own apparent diameter as seen from the Earth every hour. This also sets us up for four more fine occultations of Aldebaran by the Moon alternating between Europe and North America on October 2^nd, October 29^th, November 26^th, and December 23^rd.

The bright stars Antares, Spica and Regulus also lie along the path of the Moon, which is inclined about five degrees relative to the ecliptic. A series of occultations of Regulus by the Moon begins in late 2016.

Fun fact: The Moon used to occult the bright star Pollux in the constellation Gemini until about 2100 years ago in 117 BC. The 26,000 year cycle known as the Precession of the Equinoxes has since carried the star out of the Moon’s path.

Observations of occultations — especially dramatic grazes spied right from the edge of the path — can be used to construct a profile of the lunar limb. A step-wise ‘wink out’ of a star during an occultation can also betray the existence of a close binary.

Recording an occultation of a star by the Moon is as easy as running video while shooting the Moon. The dark limb egress of Aldebaran will be much easier to record during the September 5^th event than the ingress of the star against the bright limb. I typically run video with a DLSR directly coupled to a Celestron 8” SCT telescope, with WWV radio running in the background for a precise audio timing of the event. Remember, the Moon will also be transiting the Hyades star cluster as well, covering and uncovering many fainter stars for observers worldwide around the same time frame.

Sept 5 5UT — The Last Quarter Moon versus Aldebaran and the Hyades on September 5th at ~5:00 UT. Image credit: Stellarium

Now for the ‘wow’ factor. The Moon is about 240,000 miles (400,000 km), or 1 1/4 light seconds distant. Aldebaran is 65 light years away, and said light left the star around 1950, only to have its light ‘rejected’ during the very last second by the craggy mountains along the lunar limb. And though Aldebaran appears to be a member of the Hyades, it isn’t, as the open cluster sits 153 light years from Earth.

And watch that Moon, as it then heads for a partial solar eclipse as seen from South Africa and the southern Indian Ocean on September 13th, and a total lunar eclipse visible from North America and Europe on September 28th.

Expect more to come, with complete guides to both on Universe Today!

August 30, 2015December 23, 2015 by Ken Kremer

NASA Tests Orion’s Fate During Parachute Failure Scenario

A test version of NASA's Orion spacecraft successfully landed under two main parachutes in the Arizona desert Aug. 26, 2015 at the U.S. Army's Yuma Proving Ground. Credit: NASA

What would happen to the astronaut crews aboard NASA’s Orion deep space capsule in the event of parachute failures in the final moments before splashdown upon returning from weeks to years long forays to the Moon, Asteroids or Mars?

NASA teams are evaluating Orion’s fate under multiple scenarios in case certain of the ships various parachute systems suffer partial deployment failures after the blistering high speed reentry into the Earth’s atmosphere.

Orion is nominally outfitted with multiple different parachute systems including two drogue chutes and three main chutes that are essential for stabilizing and slowing the crewed spacecraft for safely landing in the Pacific Ocean upon concluding a NASA ‘Journey to Mars’ mission.”

This week engineers from NASA and prime contractor Lockheed Martin ran a dramatic and successful six mile high altitude drop test in the skies over the Arizona desert, in the instance where one of the parachutes in each of Orion’s drogue and main systems was intentionally set to fail.

“We test Orion’s parachutes to the extremes to ensure we have a safe system for bringing crews back to Earth on future flights, even if something goes wrong,” says CJ Johnson, project manager for Orion’s parachute system, in a statement.

“Orion’s parachute performance is difficult to model with computers, so putting them to the test in the air helps us better evaluate and predict how the system works.”

Although Orion hits the atmosphere at over 24,000 mph after returning from deep space, it slows significantly after atmospheric reentry.

By the time the first parachutes normally deploy, the crew module has decelerated to some 300 mph. Their job is to slow the craft down to about 20 mph by the time of ocean splashdown mere minutes later.

On Aug. 26, NASA conducted a 35,000 foot high drop test out of the cargo bay of a C-17 aircraft using an engineering test version of the Orion capsule over the U.S. Army Yuma Proving Ground in Yuma, Arizona.

“The engineering model has a mass similar to that of the Orion capsule being developed for deep space missions, and similar interfaces with its parachute system,” say officials.

“Engineers purposefully simulated a failure scenario in which one of the two drogue parachutes, used to slow and stabilize Orion at high altitude, and one of its three main parachutes, used to slow the crew module to landing speed, did not deploy.”

Here’s a video detailing the entire drop test sequence of events from preflight preparations to the parachute landing.

The high-risk Aug. 26 experiment was NASA’s penultimate drop test in this engineering evaluations series. A new series of tests in 2016 will serve to qualify the parachute system for crewed flights.

Engineers prepare to test the parachute system for NASA’s Orion spacecraft at the U.S. Army Yuma Proving Ground in Yuma, Arizona on Aug. 26, 2015 by loading a test version on a C-17 aircraft. Credit: NASA

The parachutes operated flawlessly during the Orion EFT-1 mission.

Orion’s next launch is set for the uncrewed test flight called Exploration Mission-1 (EM-1). It will blast off on the inaugural flight of NASA’s SLS heavy lift monster rocket concurrently under development – from Launch Complex 39-B at the Kennedy Space Center.

The maiden SLS test flight is targeted for no later than November 2018 and will be configured in its initial 70-metric-ton (77-ton) version with a liftoff thrust of 8.4 million pounds. It will boost an unmanned Orion on an approximately three week long test flight beyond the Moon and back.

Toward that goal, NASA is also currently testing the RS-25 first stage engines that will power SLS – as outlined in my recent story here.

NASA plans to gradually upgrade the SLS to achieve an unprecedented lift capability of 130 metric tons (143 tons), enabling the more distant missions even farther into our solar system.

Stay tuned here for Ken’s continuing Earth and Planetary science and human spaceflight news.

Ken Kremer

………….

Learn more about MUOS-4 USAF launch, Orion, SLS, SpaceX, Boeing, ULA, Space Taxis, Mars rovers, Orbital ATK, Antares, NASA missions and more at Ken’s upcoming outreach events:

Aug 31- Sep 2: “MUOS-4 launch, Orion, Commercial crew, Curiosity explores Mars, Antares and more,” Kennedy Space Center Quality Inn, Titusville, FL, evenings

August 30, 2015December 23, 2015 by Bob King

Eclipse By Fire! Smoky Haze Pervades Night Sky, Darkens Moon

The Full Moon at 10:30 p.m. last night (Aug. 30). Even at 25 altitude, it glowed a deep, dark orange due to heavy smoke from western forest fires. Credit: Bob King

Did you see the Moon last night? I walked outside at 10:30 p.m. and was stunned to see a dark, burnt-orange Full Moon as if September’s eclipse had arrived a month early. Why? Heavy smoke from forest fires in Washington, California and Montana has now spread to cover nearly half the country in a smoky pall, soaking up starlight and muting the moonlight.

If this is what global warming has in store for us, skywatchers will soon have to take a forecast of “clear skies” with a huge grain of salt.

The Pacific Northwest is abundantly dotted with wildfires in Washington, Oregon, Idaho and Montana.This natural-color satellite image was made using the Aqua satellite on August 25, 2015. Actively burning areas, detected by MODIS’s thermal bands, are outlined in red. Credit: NASA image courtesy Jeff Schmaltz, MODIS Rapid Response Team — The Pacific Northwest is abundantly dotted with wildfires in Washington, Oregon, Idaho and Montana in this Aqua satellite image taken on August 25, 2015. Actively burning areas, detected by MODIS’s thermal bands, are outlined in red. Smoke from the fires has been drifting east, blanketing Midwestern skies and blotting out the stars at night. Credit: NASA image courtesy Jeff Schmaltz, MODIS Rapid Response Team

By day, the sky appears the palest of blues. By night, the stars are few if any, and the Moon appears faint, the color of fire and strangely remote. Despite last night’s clear skies, only the star Vega managed to penetrate the gloom. I never saw my shadow even at midnight when the Moon had climbed high into the southern sky.

Last night's Full Moon seen through an 8-inch telescope. The colors are true. Credit: Bob King — Last night’s Full Moon seen through an 8-inch telescope at 11:30 p.m. The colors are true. Credit: Bob King

We’ve seen this smoke before. Back in July, Canadian forest fires wafted south and west and covered much of the northern half of the U.S., giving us red suns in the middle of the afternoon and leaving only enough stars to count with two hands at night. On the bright side, the Moon is fascinating to observe. I set up the telescope last night and spend a half hour watching this unexpected “eclipse”; sunsets appear positively atomic. The size of the smoke particles is just right for filtering out or scattering away blues, greens and even yellow from white light. Vivid reds, pinks and oranges remain to tint anything bright enough to penetrate the haze.

GOES-8 satellite view of the central U.S. taken at 8:15 a.m. CDT August 30, 2015 show a veil of grayish forest fire smoke covering much of the Midwest with clearer conditions to the southeast. The red line is the approximate border between the two. Credit: NOAA

But smoke can cause harm, too. Forest fire smoke contains carbon monoxide, carbon dioxide and soot. On especially smoky days, you can even smell the odor of burning trees in the air at ground level. Some may suffer from burning eyes, asthma or bronchitis on especially smoky days even a thousand miles from the source fires.

Wide-angle view of last night's melon Moon. Notice that the smoke is thicker along the horizontal left and right of the Moon. Above, at a higher elevation, we see through less smoke, so the moonlit sky is a little brighter there. No stars are visible. Credit: Bob King — Wide-angle view of last night’s Moon. Notice that the smoke is thicker along the horizontal – left and right of the Moon. Above, at a higher elevation, we see through less smoke, so the moonlit sky is a bit brighter there. No stars are visible. Credit: Bob King

On clear, blue-sky days, I’ve watched the smoke creep in from the west. It begins a light haze and slowly covers the entire sky in a matter of several hours, often showing a banded structure in the direction of the Sun. A little smoke is OK for observing, but once it’s thick enough to redden the Moon even hours after moonrise, you can forget about using your telescope for stargazing. Sometimes, a passing thunderstorm and cold front clears the sky again. Sometimes not.

The only cures for fire soot are good old-fashioned rain and the colder weather that arrives with fall. In the meantime, many of us will spend our evenings reading about the stars instead of looking at them.

August 28, 2015December 23, 2015 by Bob King

August Full Moon Anticipates September’s Total Lunar Eclipse

A Full Moon in all its horizontal glory. When near the horizon, refraction squeezes the lunar disk into an oval. Scattering removes the shorter wavelengths of white light, leaving the Moon a rich red or orange. Credit: Bob King

Who doesn’t love a Full Moon? Occurring about once a month, they never wear out their welcome. Each one becomes a special event to anticipate. In the summer months, when the Moon rises through the sultry haze, atmosphere and aerosols scatter away so much blue light and green light from its disk, the Moon glows an enticing orange or red.

At Full Moon, we’re also more likely to notice how the denser atmosphere near the horizon squeezes the lunar disk into a crazy hamburger bun shape. It’s caused by atmospheric refraction. Air closest to the horizon refracts more strongly than air near the top edge of the Moon, in effect “lifting” the bottom of the Moon up into the top. Squished light! We also get to see all the nearside maria or “seas” at full phase, while rayed craters like Tycho and Copernicus come into their full glory, looking for all the world like giant spatters of white paint even to the naked eye.

At full phase, the Moon lies directly opposite the Sun on the other side of Earth. Sunlight hits the Moon square on and fully illuminates the Earth-facing hemisphere. Credit: Bob King

Tomorrow night (August 29), the Full Sturgeon Moon rises around sunset across the world. The name comes from the association Great Lakes Indian groups made between the August moon and the best time to catch sturgeon. Next month’s moon is the familiar Harvest Moon; the additional light it provided at this important time of year allowed farmers to harvest into the night.

A Full Moon lies opposite the Sun in the sky exactly like a planet at opposition. Earth is stuck directly between the two orbs. As we look to the west to watch the Sun go down, the Moon creeps up at our back from the eastern horizon. Full Moon is the only time the Moon faces Sun directly – not off to one side or another – as seen from Earth, so the entire disk is illuminated.

The moon provides the perfect backdrop for watching birds migrate at night. Observers with spotting scopes and small telescopes can watch the show anytime the moon is at or near full. Photo illustration: Bob King — The moon provides the perfect backdrop for watching birds migrate at night. Although a small telescope is best, you might see an occasional bird in binoculars, too. Credit: Bob King

If you’re a moonrise watcher like I am, you’ll want to find a place where you can see all the way down to the eastern horizon tomorrow night. You’ll also need the time of moonrise for your city and a pair of binoculars. Sure, you can watch a moonrise without optical aid perfectly well, but you’ll miss all the cool distortions happening across the lunar disk from air turbulence. Birds have also begun their annual migration south. Don’t be surprised if your glass also shows an occasional winged silhouette zipping over those lunar seas.

Because the Moon's orbit is tilted 5.1 degrees with respect to Earth's, it normally passes above or below Earth's shadow with no eclipse. Only when the lineup is exact, does the Moon then pass directly behind Earth and into its shadow. Credit: Bob King — Because the Moon’s orbit is tilted 5.1° with respect to Earth’s, it normally passes above or below Earth’s shadow with no eclipse — either lunar or solar. Only when the lineup is exact, does the Moon pass directly behind Earth and into its shadow. Credit: Bob King

Next month’s Full Moon is very special. A few times a year, the alignment of Sun, Earth and Moon (in that order) is precise, and the Full Moon dives into Earth’s shadow in total eclipse. That will happen overnight Sunday night-Monday morning September 27-28. This will be the final in the current tetrad of four total lunar eclipses, each spaced about six months apart from the other. I think this one will be the best of the bunch. Why?

The totally eclipsed moon on April 15, 2014 from Duluth, Minn. This was the first in the series of four eclipses called a tetrad. Some refer to this lunar eclipse as a “Blood Moon” because it coincides with the Jewish Passover. Credit: Bob King — The totally eclipsed moon on April 15, 2014 from Duluth, Minn. This was the first in the series of four eclipses called a tetrad. September’s totally eclipsed Moon will appear similar. The coloring comes from sunlight grazing the edge of Earth’s atmosphere and refracted by it into the planet’s shadow. Credit: Bob King

Convenient evening viewing hours (CDT times given) for observers in the Americas. Partial eclipse begins at 8:07 p.m., totality lasts from 9:11 – 10:23 p.m. and partial eclipse ends at 11:27 p.m. Those times mean that for many regions, kids can stay up and watch.
The Moon passes more centrally through Earth’s shadow than during the last total eclipse. That means a longer totality and possibly more striking color contrasts.
September’s will be the last total eclipse visible in the Americas until January 31, 2018. Between now and then, there will be a total of four minor penumbral eclipses and one small partial. Slim pickings.

Diagram showing the details of the upcoming total lunar eclipse. The event begins when the Moon treads into Earth's outer shadow (penumbra) at 7:12 p.m. CDT. Partial phases start at 8:07 and totality at 9:11. Credit: NASA / Fred Espenak — Diagram showing the details of the upcoming total lunar eclipse. The event begins when the Moon treads into Earth’s outer shadow (penumbra) at 7:12 p.m. CDT. Partial phases start at 8:07 and totality at 9:11. Credit: NASA / Fred Espenak

Not only will the Americas enjoy a spectacle, but totality will also be visible from Europe, Africa and parts of Asia. For eastern hemisphere skywatchers, the event will occur during early morning hours of September 28. Universal or UT times for the eclipse are as follows: Partial phase begin at 1:07 a.m., totality from 2:11 – 3:23 a.m. with the end of partial phase at 4:27 a.m.

Eclipse visibility map. Credit: NASA / Fred Espenak — September 27-28, 2015 eclipse visibility map. Credit: NASA / Fred Espenak

We’ll have much more coverage on the upcoming eclipse in future articles here at Universe Today. I hope this brief look will serve to whet your appetite and help you anticipate what promises to be one of the best astronomical events of 2015.

August 26, 2015December 23, 2015 by David Dickinson

Ice Giants at Opposition

It seems as if the planets are fleeing the evening sky, just as the Fall school star party season is getting underway. Venus and Mars have entered the morning sky, and Jupiter reaches solar conjunction this week. Even glorious Saturn has passed eastern quadrature, and will soon depart evening skies.

Enter the ice giants, Uranus and Neptune. Both reach opposition for 2015 over the next two months, and the time to cross these two out solar system planets off your life list is now.

Aug 26 — Looking east at dusk in late August, as Uranus and Neptune rise. Image credit: Stellarium

First up, the planet Neptune reaches opposition next week in the constellation Aquarius on the night of August 31^st/September 1^st. Shining at magnitude +7.8, Neptune spends the remainder of 2015 about three degrees southwest of the +3.7 magnitude star Lambda Aquarii. It’s possible to spot Neptune using binoculars, and about x100 magnification in a telescope eyepiece will just resolve the blue-grey 2.3 arc second disc of the planet. Though Neptune has 14 known moons, just one, Triton, is within reach of a backyard telescope. Triton shines at magnitude +13.5 (comparable to Pluto), and orbits Neptune in a retrograde path once every 6 days, getting a maximum of 15” from the disk of the planet.

Nep Aug-Nov Triton aug 31 — The path of Neptune from late August through early November 2015. Inset: the position of Neptune’s moon Triton on the evening of August 31st: Image credit: Starry Night Education software

Uranus reaches opposition on October 11^th in the adjacent constellation Pisces. Keep an eye on Uranus, as it nears the bright +5.2 magnitude star Zeta Piscium towards the end on 2015. Shining at magnitude +5.7 with a 3.6 arc second disk, Uranus hovers just on the edge of naked eye visibility from a dark sky site.

Credit — Uranus, left of the eclipsed Moon last October. Image credit and copyright: A Nartist

It’ll be worth hunting for Uranus on the night of September 27^th/28^th, when it sits 15 degrees east of the eclipsed Moon. Uranus turned up in many images of last Fall’s total lunar eclipse. This will be the final total lunar eclipse of the current tetrad, and the Moon will occult Uranus the evening after for the South Atlantic. This is part of a series of 19 ongoing occultations of Uranus by the Moon worldwide, which started in August 2014, and end on December 20^th, 2015. After that, the Moon will move on and begin occulting Neptune next year in June through the end of 2017.

Occultation — The visibility footprint of the September 29th occultation of Uranus by the Moon. Image credit: Occult 4.0.

Uranus has 27 known moons, four of which (Oberon, Ariel, Umbriel and Titania) are visible in a large backyard telescope. See our extensive article on hunting the moons of the solar system for more info, and the JPL/PDS rings node for corkscrew finder charts.

Uranus aug-dec moons oct12 — The path of Uranus, from late August through early December 2015. Inset: the position of the moons of Uranus on the evening of October 12th. Image credit: Starry Night Education software

The two outermost worlds have a fascinating entwined history. William Herschel discovered Uranus on the night of March 13^th, 1781. We can be thankful that the proposed name ‘George’ after William’s benefactor King George the III didn’t stick. Herschel initially thought he’d discovered a comet, until he followed the slow motion of Uranus over several nights and realized that it had to be something large orbiting at a great distance from the Sun. Keep in mind, Uranus and Neptune both crept onto star charts unnoticed pre-1781. Galileo even famously sketched Neptune near Jupiter in 1612! Early astronomers simply considered the classical solar system out to Saturn as complete, end of story.

And the hunt was on. Astronomers soon realized that Uranus wasn’t staying put: something farther still from the Sun was tugging at its orbit. Mathematician Urbain Le Verrier predicted the position of the unseen planet, and on and on the night of September 23^rd, 1846, astronomers at the Berlin observatory spied Neptune.

In a way, those early 19^th century astronomers were lucky. Neptune and Uranus had just passed each other during a close encounter in 1821. Otherwise, Neptune might’ve remained hidden for several more decades. The synodic period of the two planets—that is, the time it takes the planets to return to opposition—differ by about 2-3 days. The very first documented conjunction of Neptune and Uranus occurred back in 1993, and won’t occur again until 2164. Heck, In 2010, Neptune completed its first orbit since discovery!

To date, only one mission, Voyager 2, has given us a close-up look at Uranus and Neptune during brief flybys. The final planetary encounter for Voyager 2 occurred in late August in 1989, when the spacecraft passed 4,800 kilometres (3,000 miles) above the north pole of Neptune.

All thoughts to ponder as you hunt for the outer ice giants. Sure, they’re tiny dots, but as with many nighttime treats, the ‘wow’ factor comes with just what you’re seeing, and the amazing story behind it.