Mars’ atmosphere is about 100 times thinner than Earth’s, but there’s still a lot going on in that wispy, carbon dioxide Martian air. The MAVEN spacecraft recently took some exceptional images of Mars using its Imaging UltraViolet Spectrograph (IUVS), revealing dynamic and previously invisible subtleties.
MAVEN took the first-ever images of nightglow on Mars. You may have seen nightglow in images of Earth taken by astronauts on the International Space Station as a dim greenish light surrounding the planet. Nightglow is produced when oxygen and nitrogen atoms collide to form nitric oxide. This is ionized by ultraviolet light from the Sun during the day, and as it travels around to the nightside of the planet, it will glow in ultraviolet.
“The planet will glow as a result of this chemical reaction,” said Nick Schneider, from the Laboratory for Atmospheric and Space Physics at the University of Colorado, Boulder, speaking today at the American Astronomical Society Division for Planetary Sciences meeting. “This is a common planetary reaction that tells us about the transport of these ingredients and around the planet and show how winds circulate at high altitudes.”
MAVEN’s images show evidence of strong irregularities in Mars’ high altitude winds and circulation patterns and Schneider said these first images will lead to an improved understanding of the circulation patterns that control the behavior of the atmosphere from approximately 37 to 62 miles (about 60 to 100 kilometers) high.
MAVEN’s ultraviolet images also provide insight into cloud formation and ozone in Mars atmosphere.
The images show how water ice clouds form, especially in the afternoon, over the four giant volcanoes on Mars in the Tharsis region. Cloud formation in the afternoon is a common occurrence on Earth, as convection causes water vapor to rise.
“Water ice clouds are very common on Mars and they can tell us about water inventory on the planet,” Schneider said. “In these images you can see an incredible expansion of the clouds over the course of seven hours, forming a cloud bank that must be a thousand miles across.”
He added that this is just the kind of info scientists want to be plugging in to their circulation models to study circulation and the chemistry of Mars’ atmosphere. “This is helping us advance our understanding in these areas, and we’ll be able to study it with MAVEN through full range of Mars’ seasons.”
Schneider explained that MAVEN’s unique orbit allows it to get views of the planet that other orbiters don’t have. One part of its elliptical orbit takes it high above the planet that allows for global views, but it still orbits fast enough to get multiple views as Mars rotates over the course of a day.
“We get to see daily events evolve over time because we return to that orbit every few hours,” he said.
In addition, dayside ultraviolet imagery from the spacecraft shows how ozone amounts change over the seasons. Ozone is destroyed when water vapor is present, so ozone accumulates in the winter polar region where the water vapor has frozen out of the atmosphere. The images show ozone lasting into spring, indicating that global winds are constraining the spread of water vapor from the rest of the planet into winter polar regions.
Wave patterns in the ozone images show wind pattern, as well, helping scientists to study the chemistry and global circulation of Mars’ atmosphere.
Have you ever taken a look at a piece of firewood and said to yourself, “gee, I wonder how much energy it would take to split that thing apart”? Chances are, no you haven’t, few people do. But for physicists, asking how much energy is needed to separate something into its component pieces is actually a pretty important question.
In the field of physics, this is what is known as binding energy, or the amount of mechanical energy it would take to disassemble an atom into its separate parts. This concept is used by scientists on many different levels, which includes the atomic level, the nuclear level, and in astrophysics and chemistry.
Nuclear Force:
As anyone who remembers their basic chemistry or physics surely knows, atoms are composed of subatomic particles known as nucleons. These consist of positively-charged particles (protons) and neutral particles (neutrons) that are arranged in the center (in the nucleus). These are surrounded by electrons which orbit the nucleus and are arranged in different energy levels.
The reason why subatomic particles that have fundamentally different charges are able to exist so close together is because of the presence of Strong Nuclear Force – a fundamental force of the universe that allows subatomic particles to be attracted at short distances. It is this force that counteracts the repulsive force (known as the Coulomb Force) that causes particles to repel each other.
Therefore, any attempt to divide the nucleus into the same number of free unbound neutrons and protons – so that they are far/distant enough from each other that the strong nuclear force can no longer cause the particles to interact – will require enough energy to break these nuclear bonds.
Thus, binding energy is not only the amount of energy required to break strong nuclear force bonds, it is also a measure of the strength of the bonds holding the nucleons together.
Nuclear Fission and Fusion:
In order to separate nucleons, energy must be supplied to the nucleus, which is usually accomplished by bombarding the nucleus with high energy particles. In the case of bombarding heavy atomic nuclei (like uranium or plutonium atoms) with protons, this is known as nuclear fission.
However, binding energy also plays a role in nuclear fusion, where light nuclei together (such as hydrogen atoms), are bound together under high energy states. If the binding energy for the products is higher when light nuclei fuse, or when heavy nuclei split, either of these processes will result in a release of the “extra” binding energy. This energy is referred to as nuclear energy, or loosely as nuclear power.
It is observed that the mass of any nucleus is always less than the sum of the masses of the individual constituent nucleons which make it up. The “loss” of mass which results when nucleons are split to form smaller nucleus, or merge to form a larger nucleus, is also attributed to a binding energy. This missing mass may be lost during the process in the form of heat or light.
Once the system cools to normal temperatures and returns to ground states in terms of energy levels, there is less mass remaining in the system. In that case, the removed heat represents exactly the mass “deficit”, and the heat itself retains the mass which was lost (from the point of view of the initial system). This mass appears in any other system which absorbs the heat and gains thermal energy.
Types of Binding Energy:
Strictly speaking, there are several different types of binding energy, which is based on the particular field of study. When it comes to particle physics, binding energy refers to the energy an atom derives from electromagnetic interaction, and is also the amount of energy required to disassemble an atom into free nucleons.
In the case of removing electrons from an atom, a molecule, or an ion, the energy required is known as “electron binding energy” (aka. ionization potential). In general, the binding energy of a single proton or neutron in a nucleus is approximately a million times greater than the binding energy of a single electron in an atom.
In astrophysics, scientists employ the term “gravitational binding energy” to refer to the amount of energy it would take to pull apart (to infinity) an object held together by gravity alone – i.e. any stellar object like a star, a planet, or a comet. It also refers to the amount of energy that is liberated (usually in the form of heat) during the accretion of such an object from material falling from infinity.
Finally, there is what is known as “bond” energy, which is a measure of the bond strength in chemical bonds, and is also the amount of energy (heat) it would take to break a chemical compound down into its constituent atoms. Basically, binding energy is the very thing that binds our Universe together. And when various parts of it are broken apart, it is the amount of energy needed to carry it out.
The study of binding energy has numerous applications, not the least of which are nuclear power, electricity, and chemical manufacture. And in the coming years and decades, it will be intrinsic in the development of nuclear fusion!
NASA WALLOPS FLIGHT FACILITY, VA – The ‘Return to Flight’ blastoff of Orbital ATK’s upgraded Antares rocket will have to wait one more day to come to fruition with a magnificent Monday night launch – after a technical scrub was called this afternoon, Oct. 16, at NASA’s Virginia launch base due to a faulty cable.
The launch potentially offers a thrilling skyshow to millions of US East Coast spectators if all goes well.
Despite picture perfect Fall weather, technical gremlins intervened to halt Sunday nights planned commercial cargo mission for NASA carrying 2.5 tons of science and supplies bound for the International Space Station (ISS).
The launch of the Orbital ATK CRS-5 mission is now scheduled for October 17 at 7:40 p.m. EDT, from the Mid-Atlantic Regional Spaceport pad 0A at NASA’s Wallops Flight Facility on Virginia’s picturesque Eastern shore.
You can watch the launch live on NASA TV as well as the agency’s website beginning at 6:30 p.m. EDT Oct 17.
Mondays liftoff is slated to take place approximately 23 minutes earlier then Sunday’s hoped for time of 8:03 p.m. EDT in order to match the moment when the orbital plane of the station passes on NASA Wallops.
The weather outlook on Monday remains extremely favorable with a 95 percent chance of acceptable conditions at launch time.
A nearly full moon has risen over Antares the past few days at the launch pad.
Announcement of the launch scrub of the mission – also known as OA-5 – came just as the six hour countdown was set to begin after engineers discovered the bad cable.
“Today’s launch of Orbital ATK’s Antares rocket is postponed 24 hours due to a ground support equipment (GSE) cable that did not perform as expected during the pre-launch check out,” officials at NASA Wallops said.
The faulty cable was a component of the rocket’s hold down system at the pad, Orbital ATK officials told Universe Today after the scrub was announced.
Technicians have spares on hand and are working now to replace the cable in time to permit a Monday evening launch.
“We have spares on hand and rework procedures are in process. The Antares and Cygnus teams are not currently working any technical issues with the rocket or the spacecraft.”
Besides the cable the rocket is apparently in perfect shape.
“The Antares and Cygnus teams are not currently working any technical issues with the rocket or the spacecraft.”
Antares launches have been on hold for two years after it was grounded following its catastrophic failure just moments after liftoff on Oct. 28, 2014 that doomed the Orb-3 resupply mission to the space station – as witnessed by this author.
Orbital ATK’s Antares commercial rocket had to be overhauled with the completely new RD-181 first stage engines- fueled by LOX/kerosene – following the destruction of the Antares rocket and Cygnus supply ship two years ago.
The 14 story tall commercial Antares rocket also will launch for the first time in the upgraded 230 configuration – powered by new Russian-built first stage engines designed and manufactured by Energomesh.
The 133-foot-tall (40-meter) Antares was rolled out to pad 0A on Thursday, Oct. 13 – three days prior to Sunday’s intended launch date. It was raised to the vertical launch position on Friday.
The two stage Antares will carry the Orbital OA-5 Cygnus cargo freighter to orbit on a flight bound for the ISS and its multinational crew of astronauts and cosmonauts.
The launch marks the first nighttime liftoff of the Antares – and it could be visible up and down the eastern seaboard if weather and atmospheric conditions cooperate to provide a spectacular viewing opportunity to the most populated region in North America.
The Cygnus spacecraft for the OA-5 mission is named the S.S. Alan G. Poindexter in honor of former astronaut and Naval Aviator Captain Alan Poindexter.
Under the Commercial Resupply Services (CRS) contract with NASA, Orbital ATK will deliver approximately 28,700 kilograms of cargo to the space station. OA-5 is the sixth of these missions.
Watch for Ken’s continuing Antares/Cygnus mission and launch reporting. He will be reporting from on site at NASA’s Wallops Flight Facility, VA during the launch campaign.
Stay tuned here for Ken’s continuing Earth and Planetary science and human spaceflight news.
A volcano is an impressive sight. When they are dormant, they loom large over everything on the landscape. When they are active, they are a destructive force of nature that is without equal, raining fire and ash down on everything in site. And during the long periods when they are not erupting, they can also be rather beneficial to the surrounding environment.
But just what causes volcanoes? When it comes to our planet, they are the result of active geological forces that have shaped the surface of the Earth over the course of billions of years. And interestingly enough, there are plenty of examples of volcanoes on other bodies within our Solar System as well, some of which put those on Earth to shame!
Definition:
By definition, a volcano is a rupture in the Earth’s (or another celestial body’s) crust that allows hot lava, volcanic ash, and gases to escape from a magma chamber located beneath the surface. The term is derived from Vulcano, a volcanically-active island located of the coast of Italy who’s name in turn comes from the Roman god of fire (Vulcan).
On Earth, volcanoes are the result of the action between the major tectonic plates. These sections of the Earth’s crust are rigid, but sit atop the relatively viscous upper mantle. The hot molten rock, known as magma, is forced up to the surface – where it becomes lava. In short, volcanoes are found where tectonic plates are diverging or converging – such as the Mid-Atlantic Ridge or the Pacific Ring of Fire – which causes magma to be forced to the surface.
Volcanoes can also form where there is stretching and thinning of the crust’s interior plates, such as in the the East African Rift and the Rio Grande Rift in North America. Volcanism can also occur away from plate boundaries, where upwelling magma is forced up into brittle sections of the crust, forming volcanic islands – such as the Hawaiian islands.
Erupting volcanoes pose many hazards, and not just to the surrounding countryside. In their immediate vicinity, hot, flowing lava can cause extensive damage to the environment, property, and endanger lives. However, volcanic ash can cause far-reaching damage, raining sulfuric acid, disrupting air travel, and even causing “volcanic winters” by obscuring the Sun (thus triggering local crop failures and famines).
Types of Volcanoes:
There are four major types of volcanoes – cinder cone, composite and shield volcanoes, and lava domes. Cinder cones are the simplest kind of volcano, which occur when magma is ejected from a volcanic vent. The ejected lava rains down around the fissure, forming an oval-shaped cone with a bowl-shaped crater on top. They are typically small, with few ever growing larger than about 300 meters (1,000 feet) above their surroundings.
Composite volcanoes (aka. stratovolcanoes) are formed when a volcano conduit connects a subsurface magma reservoir to the Earth’s surface. These volcanoes typically have several vents that cause magma to break through the walls and spew from fissures on the sides of the mountain as well as the summit.
These volcanoes are known for causing violent eruptions. And thanks to all this ejected material, these volcanoes can grow up to thousands of meters tall. Examples include Mount Rainier (4,392 m; 14,411 ft), Mount Fuji (3,776 m; 12,389 ft), Mount Cotopaxi (5,897 m; 19,347 ft) and Mount Saint Helens (2,549 mm; 8,363 ft).
Shield volcanoes are so-named because of their large, broad surfaces. With these types of volcanoes, the lava that pours forth is thin, allowing it to travel great distances down the shallow slopes. This lava cools and builds up slowly over time, with hundreds of eruptions creating many layers. They are therefore not likely to be catastrophic. Some of the best known examples are those that make up the Hawaiian Islands, especially Mauna Loa and Mauna Kea.
Volcanic or lava domes are created by small masses of lava which are too viscous to flow very far. Unlike shield volcanoes, which have low-viscosity lava, the slow-moving lava simply piles up over the vent. The dome grows by expansion over time, and the mountain forms from material spilling off the sides of the growing dome. Lava domes can explode violently, releasing a huge amount of hot rock and ash.
Volcanoes can also be found on the ocean floor, known as submarine volcanoes. These are often revealed through the presence of blasting steam and rocky debris above the ocean’s surface, though the pressure of the ocean’s water can often prevent an explosive release.
In these cases, lava cools quickly on contact with ocean water, and forms pillow-shaped masses on the ocean floor (called pillow lava). Hydrothermal vents are also common around submarine volcano, which can support active and peculiar ecosystems because of the energy, gases and minerals they release. Over time, the formations created by submarine volcanoes may become so large that they become islands.
Volcanoes can also developed under icecaps, which are known as subglacial volcanoes. In these cases, flat lava flows on top of pillow lava, which results from lava quickly cooling upon contact with ice. When the icecap melts, the lava on top collapses, leaving a flat-topped mountain. Very good examples of this type of volcano can be seen in Iceland and British Columbia, Canada.
Examples on Other Planets:
Volcanoes can be found on many bodies within the Solar System. Examples include Jupiter’s moon Io, which periodically experiences volcanic eruptions that reach up to 500 km (300 mi) into space. This volcanic activity is caused by friction or tidal dissipation produced in Io’s interior, which is responsible for melting a significant amount of Io’s mantle and core.
It’s colorful surface (orange, yellow, green, white/grey, etc.) shows the presence of sulfuric and silicate compounds, which were clearly deposited by volcanic eruptions. The lack of impact craters on its surface, which is uncommon on a Jovian moon, is also indicative of surface renewal.
Mars has also experienced intense volcanic activity in its past, as evidenced by Olympus Mons – the largest volcano in the Solar System. While most of its volcanic mountains are extinct and collapsed, the Mars Express spacecraft observed evidence of more recent volcanic activity, suggesting that Mars may still be geologically active.
Much of Venus’ surface has been shaped by volcanic activity as well. While Venus has several times the number of Earth’s volcanoes, they were believed to all be extinct. However, there is a multitude of evidence that suggests that there may still be active volcanoes on Venus which contribute to its dense atmosphere and runaway Greenhouse Effect.
For instance, during the 1970s, multiple Soviet Venera missions conducted surveys of Venus. These missions obtained evidence of thunder and lightning within the atmosphere, which may have been the result of volcanic ash interacting with the atmosphere. Similar evidence was gathered by the ESA’s Venus Express probe in 2007.
This same mission observed transient localized infrared hot spots on the surface of Venus in 2008 and 2009, specifically in the rift zone Ganis Chasma – near the shield volcano Maat Mons. The Magellan probe also noted evidence of volcanic activity from this mountain during its mission in the early 1990s, using radar-sounding to detect ash flows near the summit.
Cryovolcanism:
In addition to “hot volcanoes” that spew molten rock, there are also cryovolcanoes (aka. “cold volcanoes”). These types of volcanoes involve volatile compounds – i.e. water, methane and ammonia – instead of lava breaking through the surface. They have been observed on icy bodies in the Solar System where liquid erupts from ocean’s hidden in the moon’s interior.
For instance, Jupiter’s moon Europa, which is known to have an interior ocean, is believed to experiences cryovolcanism. The earliest evidence for this had to do with its smooth and young surface, which points towards endogenic resurfacing and renewal. Much like hot magma, water and volatiles erupt onto the surface where they then freeze to cover up impact craters and other features.
In addition, plumes of water were observed in 2012 and again in 2016 using the Hubble Space Telescope. These intermittent plumes were observed on both occasions to be coming in the southern region of Europa, and were estimated to be reach up to 200 km (125 miles) before depositing water ice and material back onto the surface.
In 2005, the Cassini-Huygens mission detected evidence of cryovolcanism on Saturn’s moons Titan and Enceladus. In the former case, the probe used infrared imaging to penetrate Titan’s dense clouds and detect signs of a 30 km (18.64 mi) formation, which was believed to be caused by the upwelling of hydrocarbon ices beneath the surface.
On Enceladus, cryovolcanic activity has been confirmed by observing plumes of water and organic molecules being ejected from the moon’s south pole. These plumes are are thought to have originated from the moon’s interior ocean, and are composed mostly of water vapor, molecular nitrogen, and volatiles (such as methane, carbon dioxide and other hydrocarbons).
In 1989, the Voyager 2 spacecraft observed cryovolcanoes ejecting plumes of water ammonia and nitrogen gas on Neptune’s moon Triton. These nitrogen geysers were observed sending plumes of liquid nitrogen 8 km (5 mi) above the surface of the moon. The surface is also quite young, which was seen as indication of endogenic resurfacing. It is also theorized that cryovolcanism may also be present on the Kuiper Belt Object Quaoar.
Here on Earth, volcanism takes the form of hot magma being pushed up through the Earth’s silicate crust due to convention in the interior. However, this kind of activity is present on all planet that formed from silicate material and minerals, and where geological activity or tidal stresses are known to exist. But on other bodies, it consists of cold water and materials from the interior ocean being forced through to the icy surface.
Today, our knowledge of volcanism (and the different forms it can take) is the result of improvements in both the field of geology, as well as space exploration. The more we learn of about other planets, the more we are able to see startling similarities and contrasts with our own (and vice versa).
Those who live along the “wet coast” – which is what people living in Puget Sound or the lower mainland of British Columbia and Vancouver Island affectionately call their home – might think that they live in the wettest place on Earth. Then again, people living in the Amazon rain forest might think that there lush and beautiful home is the dampest place in the world.
But in truth, all these places come up dry (pun intended!) compared to the one place that has held the title for wettest point on Earth many times in its history. And that place is none other than Mawsynram, India, which experiences an annual average rainfall of 12 meters. And yet, this curious region in northwestern part of the Indian subcontinent is an exercise in extremes, either drowning in rainwater, or starving for it.
Annual Rainfall:
When it comes to describing locations on planet Earth in terms of “wet”, some clarifications are needed. What we are talking about is average annual precipitation – i.e. rainfall, snow, drizzle, fog, etc. – measured in mm (or inches). This is necessary because otherwise, the “wettest” place on Earth would be the Mariana Trench, which has over 10,000 meters (36,000 feet) of water on top of it.
Also, based on rainfall. the wettest place on Earth has been known to change from time to time. In recent years, that title has gone to the town of Mawsynram, a village located in the East Khasi Hills district of northeastern, India. With an average annual rainfall of 11,872 millimetres (467.4 in), it is arguably the wettest place on Earth.
However, it is often in competition with the neighboring town of Cherrapunjee, which is located just 15 km (9.3 mi) to the west of Mawsynram in the East Khasi Hills district in northeastern India. The city’s yearly rainfall average stands at 11,777 millimetres (463.7 in), so it too has held the title.
The reason for these town experiencing so much precipitation has to do with the local climate. Situated within a subtropical highland climate zone, it experiences a lengthy and powerful monsoon season. In once instance, the monsoon season lasted for 2 years straight with no reported break in the rain!
Surprisingly, the high rainfall is a result of the region’s elevation and not the monsoon season alone. Huge amounts of warm air condense and fall as rain when they encounter the Khasi Hills. The topography of the region forces the very moist clouds up and down, forcing them to empty their accumulated water over the region.
Other Locations:
Beyond northeastern India, there are several other locations on the planet that experience over 10 meters (32.8 feet) of annual precipitation. For instance, the town of Tutunendo, Colombia, experiences an average of 11,770 mm (463.38 in) of annual rainfall. The area actually experiences two rainy seasons a year, so precipitation is pretty much the norm.
Next up, there is Mount Waialeale, a shield volcano located on the island of Kaua’i on the Hawaiian Islands. As the the second highest point on the island, its name literally means “rippling water” (or “overflowing water”), and for good reason! This mountain has had an average of 11,500 mm (452 in) of rainfall since 1912.
However, in 1982, its summit experienced 17,300 mm (683 in), making it the wettest place on Earth in that year. And between 1978-2007, Big Bog – a spot in Haleakala National Park on the island of Maui, Hawaii – experienced an average of 10,300 mm (404 in) of rainfall, putting it in the top ten.
As already noted, the “wettest place on Earth” changes over time. This should come as no surprise, considering that weather patterns have been known to shift, not only in the course of an average year, but also over the course of centuries and millennia.
Nevertheless, those places that experience over 10 meters of precipitation are generally found within the tropical regions of the world, places known for experiencing intense and prolonged rainy seasons, and where lush tropical rainforests have existed for thousands of years. Here is a recent list of the top 10 locations.
But with anthropogenic climate change becoming a growing factor in planetary weather systems, this too could be subject to change. In the coming decades, and centuries, who’s to say where the most precipitation will fall on planet Earth?
We often hear how the Moon’s appearance hasn’t changed in millions or even billions of years. While micrometeorites, cosmic rays and the solar wind slowly grind down lunar rocks, the Moon lacks erosional processes such as water, wind and lurching tectonic plates that can get the job done in a hurry.
Remember Buzz Aldrin’s photo of his boot print in the lunar regolith? It was thought the impression would last up to 2 million years. Now it seems that estimate may have to be revised based on photos taken by the Lunar Reconnaissance Orbiter (LRO) that reveal that impacts are transforming the surface much faster than previously thought.
The LRO’s high resolution camera, which can resolve features down to about 3 feet (1-meter) across, has been peering down at the Moon from orbit since 2009. Taking before and after images, called temporal pairs, scientists have identified 222 impact craters that formed over the past 7 years. The new craters range from 10 feet up to 141 feet (3-43 meters) in diameter.
By analyzing the number of new craters and their size, and the time between each temporal pair, a team of scientists from Arizona State University and Cornell estimated the current cratering rate on the Moon. The result, published in Nature this week, was unexpected: 33% more new craters with diameters of at least 30 feet (10 meters) were found than anticipated by previous cratering models.
Similar to the crater that appeared on March 17, 2013 (above), the team also found that new impacts are surrounded by light and dark reflectance patterns related to material ejected during crater formation. Many of the larger impact craters show up to four distinct bright or dark reflectance zones. Nearest to the impact site, there are usually zone of both high and low reflectance. These two zones likely formed as a layer of material that was ejected from the crater during the impact shot outward to about 2½ crater diameters from the rim.
From analyzing multiple impact sites, far flung ejecta patterns wrap around small obstacles like hills and crater rims, indicating the material was traveling nearly parallel to the ground. This kind of path is only possible if the material was ejected at very high speed around 10 miles per second or 36,000 miles per hour! The jet contains vaporized and molten rock that disturb the upper layer of lunar regolith, modifying its reflectance properties.
How LRO creates temporal pairs and scientists use them to discover changes on the moon’s surface.
In addition to discovering impact craters and their fascinating ejecta patterns, the scientists also observed a large number of small surface changes they call ‘splotches’ most likely caused by small, secondary impacts. Dense clusters of these splotches are found around new impact sites suggesting they may be secondary surface changes caused by material thrown out from a nearby primary impact. From 14,000 temporal pairs, the group identified over 47,000 splotches so far.
Based on estimates of size, depth and frequency of formation, the group estimated that the relentless churning caused by meteoroid impacts will turn over 99% of the lunar surface after about 81,000 years. Keep in mind, we’re talking about the upper regolith, not whole craters and mountain ranges. That’s more than 100 times faster than previous models that only took micrometeorites into account. Instead of millions of years for those astronaut boot prints and rover tracks to disappear, it now appears that they’ll be wiped clean in just tens of thousands!
NASA WALLOPS FLIGHT FACILITY, VA – After a two year stand down, an upgraded commercial Antares rocket was rolled out to the NASA Wallops launch pad on Virginia’s eastern shore and raised to its launch position today in anticipation of a spectacular Sunday night liftoff, Oct. 16, to the International Space Station (ISS) on a critical resupply mission for NASA.
Blastoff of the re-engined Orbital ATK Antares rocket is slated for 8:03 p.m. EDT on Oct. 16 from the Mid-Atlantic Regional Spaceport pad 0A at NASA’s Wallops Flight Facility on Virginia’s picturesque Eastern shore.
Officials had to postpone this commercial resupply mission – dubbed OA-5 – from mid-week due to Cat 3 Hurricane Nicole which slammed into Bermuda yesterday, Oct. 13, packing winds of about 125 mph, and is home to a critical NASA launch tracking station.
After the storm passed, engineers found the tracking station only suffered minor damage – so the GO was given to proceed with preparation for Sunday’s nighttime launch.
“Repairs to the station have been made and the team is currently readying to support the launch,” according to NASA officials.
Engineers are still testing the station to ensure its readiness.
“The Bermuda site provides tracking, telemetry and flight terminations support for Antares launches from NASA’s Wallops Flight Facility on Virginia’s Eastern Shore. Final testing is scheduled to be conducted the morning of Oct. 15 prior to the launch readiness review later that day.”
If all goes well Antares is sure to provide a dazzling nighttime skyshow from NASA’s Virginia launch base Sunday night – and potentially offering a thrilling spectacle to millions of US East Coast spectators.
The launch window last five minutes and the weather outlook is currently favorable.
The launch will air live on NASA TV and the agency’s website beginning at 7 p.m. EDT Oct 16.
The 133-foot-tall (40-meter) Antares was rolled out to pad 0A on Thursday, Oct. 13 – three days prior to the anticipated launch date – and raised to the vertical launch position this afternoon.
The two stage Antares will carry the Orbital OA-5 Cygnus cargo freighter to orbit on a flight bound for the ISS and its multinational crew of astronauts and cosmonauts.
The launch marks the first nighttime liftoff of the Antares – and it could be visible up and down the eastern seaboard if weather and atmospheric conditions cooperate to provide a spectacular viewing opportunity to the most populated region in North America.
The 14 story tall commercial Antares rocket also will launch for the first time in the upgraded 230 configuration – powered by new Russian-built first stage engines.
Orbital ATK’s Antares commercial rocket had to be overhauled with the completely new RD-181 first stage engines – fueled by LOX/kerosene – following the destruction of the Antares rocket and Cygnus supply ship two years ago.
The RD-181 replaces the previously used AJ26 engines which failed moments after liftoff during the last launch on Oct. 28, 2014 resulting in a catastrophic loss of the rocket and Cygnus cargo freighter.
The launch mishap was traced to a failure in the AJ26 first stage engine turbopump and caused Antares launches to immediately grind to a halt.
For the OA-5 mission, the Cygnus advanced maneuvering spacecraft will be loaded with approximately 2,400 kg (5,290 lbs.) of supplies and science experiments for the International Space Station (ISS).
“Cygnus is loaded with the Saffire II payload and a nanoracks cubesat deployer,” Frank DeMauro, Orbital ATK Cygnus program manager, told Universe Today in a interview.
Among the science payloads aboard the Cygnus OA-5 mission is the Saffire II payload experiment to study combustion behavior in microgravity. Data from this experiment will be downloaded via telemetry. In addition, a NanoRack deployer will release Spire Cubesats used for weather forecasting. These secondary payload operations will be conducted after Cygnus departs the space station.
Other experiments include a study on the effect of lighting on sleep and daily rhythms, collection of health-related data, and a new way to measure neutrons.
Watch for Ken’s continuing Antares/Cygnus mission and launch reporting. He will be reporting from on site at NASA’s Wallops Flight Facility, VA during the launch campaign.
The Cygnus spacecraft for the OA-5 mission is named the S.S. Alan G. Poindexter in honor of former astronaut and Naval Aviator Captain Alan Poindexter.
Under the Commercial Resupply Services (CRS) contract with NASA, Orbital ATK will deliver approximately 28,700 kilograms of cargo to the space station. OA-5 is the sixth of these missions.
Stay tuned here for Ken’s continuing Earth and Planetary science and human spaceflight news.
In the northern hemisphere of Mars, between the planet’s southern highlands and the northern lowlands, is a hilly region known as Colles Nilli. This boundary-marker is a very prominent feature on Mars, as it is several kilometers in height and surrounded by the remains of ancient glaciers.
And thanks to the Mars Express mission, it now looks like this region is also home to some buried glaciers. Such was the conclusion after the orbiting spacecraft took images that revealed a series of eroded blocks along this boundary, which scientists have deduced are chunks of ice that became buried over time.
The Mars Express images show a plethora of these features along the north-south boundary. They also reveal several features that hint at the presence of buried ice and erosion – such as layered deposits as well as ridges and troughs. Similar features are also found in nearby impact craters. All of these are believed to have been caused by an ancient glacier as it retreated several hundred million years ago.
It is further reasoned that these remaining ice deposits were covered by debris that was deposited from the plateau as it eroded. Wind-borne dust was also deposited over time, which is believed to be the result of volcanic activity. This latter source is evidenced by steaks of dark material deposited around the blocks, as well as dark sand dunes spotted within the impact craters.
Similar features are believed to exist within many boundary regions on Mars, and are believed to represent periods of glaciation that took place over the course of eons. And this is not the first time buried glaciers have been spotted on Mars.
For instance, back in 2008, the Mars Reconnaissance Orbiter (MRO) used its ground-penetrating radar to locate water ice under blankets or rocky debris, and at latitudes far lower than any that had been previously identified. At the time, this information shed light on a long-standing mystery about Mars, which was the presence of what are called “aprons”.
These gently-sloping rocky deposit, which are found at the bases of taller features, were first noticed by NASA’s Viking orbiters during the 1970s. A prevailing theory has been that these aprons are the result of rocky debris lubricated by small amounts of ice.
Combined with this latest info taken from the northern hemisphere, it would appear that there is plenty of ice deposits all across the surface of Mars. The presence (and prevalence) of these icy remnants offer insight into Mars’ geological past, which – like Earth – involved some “ice ages”.
The Mars Express mission has been actively surveying the surface of Mars since 2003. On October 19th, it will be playing a vital role as the Exomars mission inserts itself into Martian orbit and the Schiaparelli lander makes its descent and landing on the Martian surface.
Alongside the MRO and the ExoMars Orbiter, it will be monitoring signals from the lander to confirm its safe arrival, and will relay information sent from the surface during the course of its mission.
The ESA will be broadcasting this event live. And given that this mission will be the ESA’s first robotic lander to reach Mars, it should prove to be an exciting event!
Ever since human beings learned that the Milky Way was not unique or alone in the night sky, astronomers and cosmologists have sought to find out just how many galaxies there are in the Universe. And until recently, our greatest scientific minds believed they had a pretty good idea – between 100 and 200 billion.
However, a new study produced by researchers from the UK has revealed something startling about the Universe. Using Hubble’s Deep Field Images and data from other telescopes, they have concluded that these previous estimates were off by a factor of about 10. The Universe, as it turns out, may have had up to 2 trillion galaxies in it during the course of its history.
Led by Prof. Christopher Conselice of the University of Nottingham, U.K., the team combined images taken by the Hubble Space Telescope with other published data to produced a 3-D map of the Universe. They then incorporated a series of new mathematical models that allowed them to infer the existence of galaxies which are not bright enough to be observed by current instruments.
Using these, they then began reviewing how galaxies have evolved over the past 13 billion years. What they learned was quite fascinating. For one, they observed that the distribution of galaxies throughout the history of the Universe was not even. What’s more, they found that in order for everything in their calculations to add up, there had to be 10 times more galaxies in the early Universe than previously thought.
Most of these galaxies would be similar in mass to the satellite galaxies that have been observed around the Milky Way, and would be too faint to be spotted by today’s instruments. In other words, astronomers have only been able to see about 10% of the early Universe until now, because most of its galaxies were too small and faint to be visible.
As Prof. Conselice explained in a Hubble Science Release, while may help resolve a lingering debate about the structure of the Universe:
“These results are powerful evidence that a significant galaxy evolution has taken place throughout the universe’s history, which dramatically reduced the number of galaxies through mergers between them — thus reducing their total number. This gives us a verification of the so-called top-down formation of structure in the universe.”
To break it down, the “top-down model” of galaxy formation states that galaxies formed from huge gas clouds larger than the resulting galaxies. These clouds began collapsing because their internal gravity was stronger than the pressures in the cloud. Based on the speed at which the gas clouds rotated, they would either form a spiral or an elliptical galaxy.
In contrast, the “bottom-up model” states that galaxies formed during the early Universe due to the merging of smaller clumps that were about the size globular clusters. These galaxies could then have been drawn into clusters and superclusters by their mutual gravity.
In addition to helping to resolve this debate, this study also offers a possible solution to the Olbers’ Paradox (aka. “the dark night sky paradox”). Named after the 18th/19th century German astronomer Heinrich Wilhelm Olbers, this paradox addresses the question of why – given the expanse of the Universe and all the luminous matter in it – is the sky dark at night?
Based on their results, the UK team has surmised that while every point in the night sky contains part of a galaxy, most of them are invisible to the human eye and modern telescopes. This is due to a combination of factors, which includes the effects of cosmic redshift, the fact that the Universe is dynamic (i.e. always expanding) and the absorption of light by cosmic dust and gas.
Needless to say, future missions will be needed to confirm the existence of all these unseen galaxies. And in that respect, Conselice and his colleagues are looking to future missions – ones that are capable of observing stars and galaxies in the non-visible spectrum – to make that happen.
“It boggles the mind that over 90 percent of the galaxies in the universe have yet to be studied,” he added. “Who knows what interesting properties we will find when we discover these galaxies with future generations of telescopes? In the near future, the James Webb Space Telescope will be able to study these ultra-faint galaxies.”
Understanding how many galaxies have existed over time is a fundamental aspect of understanding the Universe as a whole. With every passing study that attempts to resolve what we can see with our current cosmological models, we are getting that much closer!
And be sure to enjoy this video about some of Hubble’s most stunning images, courtesy of HubbleESA:
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