Philae’s First Photos; Update on its Troubled Landing

Image from the Philae lander as it approached the surface. The dust-covered boulder at upper right is about 5 meters (16.4 feet) across. The dust might have originated through vaporization of ice on the boulder itself or deposited there by dust settling from jets elsewhere. Credit: ESA
First photo released of Comet 67P/C-G taken by Philae during its descent. The view is just 1.8 miles above the comet. Credit: ESA
First photo released of Comet 67P/C-G taken by Philae during its descent. The view is just 1.8 miles above the comet. Credit: ESA

Hey, we’re getting closer! This photo was taken by Philae’s ROLIS instrument just 1.8 miles (3 km) above the surface of 67P/Churyumov-Gerasimenko at 8:38 a.m. (CST) today. The ROLIS instrument is a down-looking imager that acquires images during the descent and doubles as a multi-wavelength close-up camera after the landing. The aim of the ROLIS experiment is to study the texture and microstructure of the comet’s surface. ROLIS (ROsetta Lander Imaging System) is a descent and close-up camera on the Philae lander.

I know, I know. You got a fever for more comet images the way Christopher Walken on Saturday Night Live couldn’t get enough cowbell.

Just to give you a flavor for the rugged landscape Philae was headed toward earlier today, this photo was taken by Rosetta at an altitude of 4.8 miles (7.7 km) from the comet's surface. Credit: ESA
Just for a little flavor of the rugged landscape Philae was headed toward earlier today, this photo was taken recently by Rosetta 4.8 miles (7.7 km) from the comet’s surface. Credit: ESA

Key scientists in a  media briefing this afternoon highlighted the good news and the bad news about the landing. We reported earlier that both the harpoons and top thrusters failed to fire and anchor the lander to the comet. Yet land it did – maybe more than once! A close study of the data returned seems to indicate that Philae, without its anchors, may have touched the surface and then lifted off again, turning itself from the residual angular momentum left over after its flywheel was shut down.  Stephan Ulamec, Philae Landing Manager, got a appreciative laugh from the crowd when he explained it this way:  Maybe today we didn’t just land once. We landed twice!”

Stephan Ulamec, Philae Lander Manager. Credit: ESA
Stephan Ulamec, Philae Lander Manager. Credit: ESA

Telemetry from the probe has been sporadic. Data streams come in strong and then suddenly cut out only to return later. These fluctuations in the radio link obviously have the scientists concerned and as yet, there’s no explanation for them. Otherwise, Philae landed in splendid fashion almost directly at the center of its planned “error ellipse”.

Instruments on Philae are functioning normally and gathering data as you read this.  Ulamec summed up the situation nicely:  “It’s complicated to land and also complicated to understand the landing.”

Scientists and mission control will work to hopefully resolve the harpoon and radio link issues. The next live webcast begins tomorrow starting at 7 a.m. (CST). Although nothing definite was said, we may see more images arriving still today, so stop by later.

Touchdown! Philae Successfully Lands on Rosetta’s Comet

Excitement ripples through the ESA control room with the news that Philae successfully landed on the comet this morning. Credit: ESA

We did it! We’re on the comet! At about 9:37 a.m. (CST) Philae touched down on Rosetta’s Comet. After traveling more than 315 million miles (508 million km) the lander’s signal arrived 28 minutes later with the fabulous news. Telemetry is trickling in and the lander’s in great health, but one small concern has arisen. We’ve just learned that the harpoons used to anchor Philae failed to fire. Mission control is considering whether to refire them to make sure the craft is stable.

Philae  postcard. Hey, it made it - a huge congratulations to ESA. Credit: ESA
Philae is now at work on the comet after successfully harpooning itself to the surface. A huge congratulations to ESA! Credit: ESA

One might think that as long as the craft is sitting still on the comet, that will do. Well, maybe. Until it’s anchored, activity from nearby jets or even vaporizing ice beneath it could flip it over. After all, Philae only weighs a gram in 67P/C-G’s gravity field. The harpoons also house the instrument that measures surface density. Presumably, without them we won’t get that data.

ESA's version of a Swiss Army knife, Philae will now probe the comet on many levels. Credit: ESA
ESA’s version of a Swiss Army knife, Philae will now probe the comet on many levels. Credit: ESA

Now that Philae has reached its target, science will begin in earnest. Here’s an illustration that describes each of the probe’s instruments. Be sure to click to enlarge.

 

Midway Between Storms: Our Guide to the 2014 Leonid Meteors

Credit:

If there’s one meteor shower that has the potential to bring on a storm of epic proportions, it’s the Leonids. Peaking once every 33 years, these fast movers hail from the Comet 55P Temple-Tuttle, and radiate from the Sickle, or backwards “question mark” asterism in the constellation Leo.  And although 2014 is an “off year” in terms of storm prospects, it’s always worth taking heed these chilly November mornings as we await the lion’s roar once again.

The prospects: 2014 sees the expected peak of the Leonids arriving around 22:00 Universal Time (UT) which is 5:00 PM EST. Locally speaking, a majority of meteor showers tend to peak in the early AM hours past midnight, as the observer’s location turns forward facing into the oncoming meteor stream. Think of driving in an early November snowstorm, with the car being the Earth and the flakes of snow as the oncoming meteors. And if you’ve (been fortunate enough?) to have never seen snow, remember that it’s the front windshield of the car going down the highway that catches all of the bugs!

This all means that in 2014, the Asian Far East will have an optimal viewing situation for the Leonids, though observers worldwide should still be vigilant. Of course, meteor showers never read online prognostications such as these, and often tend to arrive early or late.  The Leonids also have a broad range of activity spanning November 6th through November 30th.

Credit: Starry Night Education Software.
The November path of the radiant of the 2014 Leonids. Credit: Starry Night Education Software.

The predicted ideal Zenithal Hourly Rate for 2014 stands at about 15, which is well above the typical background sporadic rate, but lower than most years. Expect the actual sky position of the radiant and light pollution to lower this hourly number significantly. And speaking of light pollution, the Moon is a 21% illuminated waning crescent on the morning of November 17th, rising at around 2:00 AM local in the adjacent constellation of Virgo.

The Leonids can, once every 33 years, produce a storm of magnificent proportions. The history of Leonid observation may even extend back as far as 902 A.D., which was recorded in Arab annals as the “Year of the Stars.”

But it was the morning of November 13th, 1833 that really gained notoriety for the Leonids, and really kicked the study of meteor showers into high gear.

Credit:
A depiction of the 1868 Leonids by Étienne Léopold Trouvelot from The Trouvelot Astronomical Drawings, 1881. Image in the Public Domain.

The night was clear over the U.S. Eastern Seaboard, and frightened townsfolk were awakened to moving shadows on bedroom walls. Fire was the first thing on most people’s minds, but they were instead confronted with a stunning and terrifying sight: a sky seeming to rain stars in every direction. Churches quickly filled up, as folks reckoned the Day of Judgment had come.  The 1833 Leonid storm actually made later historical lists as one of the 100 great events in the United States for the 19th century. The storm has also been cited as single-handedly contributing to the religious fundamentalist revivals of the 1830s. Poet Walt Whitman witnessed the 1833 storm, and the song The Stars Fell on Alabama by Frank Perkins was inspired by the event as well.

Wikimedia Commons image in the Public Domain.
Live in Alabama? Then you may well possess a license plate that commemorates the 1833 Leonid Storm. Wikimedia Commons image in the Public Domain.

But not all were fearful. Astronomer Denison Olmsted was inspired to study the radiants and paths of meteor streams after the 1833 storm, and founded modern meteor science. The Leonids continued to produce storms at 33 year intervals, and there are still many observers that recall the spectacle that the Leonids produced over the southwestern U.S. back 1966, with a zenithal hourly rate topping an estimated 144,000 per hour!

We also have a personal fondness for this shower, as we were fortunate enough to witness the Leonids from the dark desert skies of Kuwait back in 1998. We estimated the shower approached a ZHR of about 900 towards sunrise, as a fireballs seemed to light up the desert once every few seconds.

Created using Stellarium.
The situation at 22:00 UT on November 17th, noting the direction of the Earth’s motion with relation to the predicted peak of the 2014 Leonid stream. Created using Stellarium.

The Leonids have subsided in recent years, and have fallen back below enhanced rates since 2002. Here’s the most recent ZHR levels as per the International Meteor Organization:

2009: ZHR=80.

2010: ZHR=32.

2011: ZHR=22.

2012: ZHR=48.

Note: 2013 the shower was, for the most part, washed out by the Full Moon.

But this year is also special for another reason.

Note that the 2014-2015 season marks the approximate halfway mark to an expected Leonid outburst around 2032. Comet 55P Tempel-Tuttle reaches perihelion on May 20th, 2031, and if activity in the late 1990s was any indication, we expect the Leonids to start picking up again around 2030 onward.

A simulated storm on the morning of November 17th, 2032. Credit: Stellarium.
A simulated Leonid storm on the morning of November 17th, 2032. Credit: Stellarium.

Observing meteors is as simple as laying back and looking up. Be sure to stay warm, and trace the trail of any suspect meteor back to the Sickle to identify it as a Leonid. The Leonid meteors have one of the fastest approach velocities of any meteor stream at 71 kilometres per second, making for quick, fleeting passages in the pre-dawn sky. Brighter bolides may leave lingering smoke trails, and we like to keep a set of binoculars handy to examine these on occasion.

Looking to do some real science? You can document how many meteors you see per hour from your location and send this in to the International Meteor Organization, which tabulates and uses these volunteer counts to characterize a given meteor stream.

Leonids Credit: NASA
The 1997 Leonids as seen from space by the MSX satellite. Credit: NASA/JPL

And taking images of Leonid meteors is as simple as setting your DSLR camera on a tripod and taking long exposure images of the night sky. Be sure to use the widest field of view possible, and aim the camera about 45 degrees away from the radiant to nab meteors in profile. We generally shoot 30 second to 3 minute exposures in series, and don’t be afraid to experiment with manual F-stop/ISO combinations to get the settings just right for the local sky conditions. And be sure to carefully review those shots on the “big screen” afterwards… nearly every meteor we’ve caught in an image has turned up this way.

Don’t miss the 2014 Leonids. Hey, we’re half way to the start of the 2030 “storm years!”

‘Naked’ Comets Could Expose Solar System’s Ancient Origin Story

Two objects with comet-like orbits flew through the solar system in 2013 and 2014, but with little to no activity on their surfaces. At left is C/2013 P2 Pan-STARRS and at right, C/2014 S3 Pan-STARRS. Credit: University of Hawaii Institute for Astronomy

What’s a comet that doesn’t look like a comet? The question sounds contradictory, but astronomers believe these objects exist. As comets pass through the solar system, they bleed ice and dust as the Sun’s effects wash over their small bodies. Over time, some of the objects can keep going like ghost ships — just without the ices that used to produce a show.

There already is a class of objects called damocloids that are believed to be extinct comets, but scientists believe they have found something new with two mysterious visitors — what they call “naked” comets — from the outer Solar System.

The two objects originate from an area that astronomers term the Oort Cloud, a hypothetical collection of icy bodies that orbit as far away as 100,000 times the Earth-Sun distance (astronomical unit). Gravitational influences then kick the objects in towards the Sun and they commence orbits that can last millions of years.

When Jan Oort first proposed this concept in the 1950s, he said that some of the objects there could have only a tiny layer of ice that would immediately evaporate during the first pass in near the Sun. That’s what astronomers think they are seeing in objects C/2013 P2 Pan-STARRS and C/2014 S3 Pan-STARRS.

The familiar solar system with its 8 planets occupies a tiny space inside a large spherical shell containing trillions of comets - the Oort Cloud. Credit: Wikimedia Commons
The familiar solar system with its 8 planets occupies a tiny space inside a large spherical shell containing trillions of comets – the Oort Cloud. Credit: Wikimedia Commons

“Objects on long-period orbits like this usually exhibit cometary tails, for example Comet ISON and Comet Hale Bopp, so we immediately knew this object was unusual,” stated Karen Meech, an astronomer at the University of Hawaii at Manoa who led the research. “I wondered if this could be the first evidence of movement of solar system building blocks from the inner solar system to the Oort Cloud.”

The automated Pan STARRS1 survey telescope found C/2013 P2 in August 2013, with astronomers remarking its orbit resembled that of a comet. But, C/2013 P2’s surface was quiet. A second look the next month with the 8-meter Gemini North telescope in Hawaii revealed a little bit of light and a dusty tail. The object stayed at about the same brightness, even when it got to its closest approach to the Sun (2.8 AU) in February 2014.

After the comet swung around the Sun and telescopes could look at it again, examinations with the Gemini North telescope found something weird: the object’s spectrum looked red. This makes it look more like a Kuiper Belt object — something that roams in shallower waters in the Solar System, beyond Neptune’s orbit — than a typical comet or asteroid.

While results were still being analyzed, in September a NASA survey found an object with curiously similar properties: C/2014 S3. When it was found, the object had already passed its closest approach to the Sun in August. But from analyzing the orbit, the scientists saw it had come to only within 2 AU. Also, the first observations showed barely a tail at all.

Distribution of Kuiper belt objects (green), along with various other outer Solar System bodies, based on data from the Minor Planet Center. [Credit:  Minor Planet Center; Murray and Dermott]
Distribution of Kuiper belt objects (green), along with various other outer Solar System bodies, based on data from the Minor Planet Center. [Credit: Minor Planet Center; Murray and Dermott]
A closer examination with the Canada-France-Hawaii Telescope revealed a mystery: the spectrum was more blue than red, hinting at materials similar to what you would find in the inner Solar System. The team says this could be a new class of objects altogether.

“I’ll be thrilled if this object turns out to have a surface composition similar to asteroids in the inner part of the asteroid belt.  If this is the case, it will be remarkable for a body found so far out in the Solar System,” stated Meech.

“There are several models that try to explain how the planets grew in the early Solar System, and some of these predict that material formed close to the sun could have been thrown outward into the outer Solar System and Oort Cloud, where it remains today. Maybe we are finally seeing that evidence.”

Results were presented today (Nov. 10) at the Division of Planetary Sciences meeting of the American Astronomical Society in Tucson, Arizona. A press release did not say if the research is peer-reviewed, or state publication plans.

Source: University of Hawaii Institute for Astronomy

What Did Isaac Newton Discover?

Godfrey Kneller's 1689 portrait of Isaac Newton at age 46. Image credit: Isaac Newton Insitute

Isaac Newton – who lived from December 25th, 1642, to March 20th, 1727 – was an English scientist, mathematician, and “natural philosopher”. In his time, he played a vital role in the Scientific Revolution, helping to advance the fields of physics, astronomy, mathematics and the natural sciences. From this, he established a legacy that would dominate the sciences for the next three centuries.

In fact, the term “Newtonian” came to be used by subsequent generations to describe bodies of knowledge that owed their existence to his theories. And because of his extensive contributions, Sir Isaac Newton is regarded as one of the most influential scholars in the history of science. But what exactly did he discover?

Newton’s Three Laws of Motion:

For starters, his magnum opus – Philosophiæ Naturalis Principia Mathematica (“Mathematical Principles of Natural Philosophy”), which was first published in 1687 – laid the foundations for classical mechanics. In it, he formulated his Three Laws of Motion, which were derived from Johann Kepler’s Laws of Planetary Motion and his own mathematical description of gravity.

William Blake's Newton (1795), depicted as a divine geometer. Image Credit: William Blake Archive/Wikipedia
William Blake’s Newton (1795), depicting him as a divine geometer. Image Credit: William Blake Archive/Wikipedia

The first law, known as the “law of inertia”, states that: “An object at rest will remain at rest unless acted on by an unbalanced force. An object in motion continues in motion with the same speed and in the same direction unless acted upon by an unbalanced force.” The second law states that acceleration is produced when a force acts on a mass – ergo, the greater the mass of the object, the greater the force required to accelerate it. The third and final law states that “for every action, there is an equal but opposite reaction”.

Universal Gravitation:

He also formulated his law of Universal Gravitation in the Principia, which states that every point mass attracts every single other point mass by a force pointing along the line intersecting both point. According to his calculations, this force is proportional to the product of the two masses and inversely proportional to the square of the distance between them. The formula for this theory can be expressed as:

F = G frac{m_1 m_2}{r^2}

Newton would go on to use these principles to account for the trajectories of comets, the tides, the precession of the equinoxes, and other astrophysical phenomena. This effectively removed the last doubts about the validity of the heliocentric model of the cosmos which argued that the Sun (not the Earth) was at the center of the planetary system. His work also demonstrated that the motion of objects on Earth and of celestial bodies could be described by the same principles.

Sapling of the reputed original tree that inspired Sir Isaac Newton to consider gravitation. Credit: Wikipedia Commons/Loodog
Sapling of the reputed original tree that inspired Sir Isaac Newton to consider gravitation. Credit: Wikipedia Commons/Loodog

Though Newton’s inspiration for his theories on gravity are often attributed to the “Apple Incident” – i.e. where he watched an apple fall from a tree – the story is considered apocryphal by modern sources who argue that he came to his conclusions over time. However, Newton himself described the incident, and contemporaries of his defend this assertion.

Shape of the Earth:

Additional contributions include his prediction that the Earth was likely shaped as an “oblate spheroid” – i.e. a sphere that experienced flattening at the poles. This theory would later be vindicated by the measurements of Maupertuis, La Condamine, and others. This in turn helped convince most Continental European scientists of the superiority of Newtonian mechanics over the earlier system of Descartes.

In terms of mathematics, he contributed to the study of power series, generalized the binomial theorem to non-integer exponents, developed Newton’s method for approximating the roots of a function, and classified most of the cubic plane curves. He also shares credit with Gottfried Leibniz for the development of calculus.

These discoveries represented a huge leap forward for the fields of math, physics, and astronomy, allowing for calculations that more accurately modeled the behavior of the universe than ever before.

Optics:

In 1666, Newton began contributing to the field of optics, first by observing that color was a property of light by measuring it through a prism. From 1670 to 1672, he lectured at the University of Cambridge on optics and investigated the refraction of light, demonstrating that the multicolored spectrum produced by a prism could be recomposed into white light by a lens and a second prism.

Sunlight passing through a prism. Image credit: NASA
Sunlight passing through a prism. Image credit: NASA

As a result of his research, he came to theorize that color is the result of objects interacting with already-colored light rather than objects generating the color themselves, which is known as Newton’s theory of color.

In addition, he concluded that the lens of any refracting telescope would suffer from the dispersion of light into colors (chromatic aberration). As a proof of the concept, he constructed a telescope using a mirror as the objective to bypass that problem. This was the first known functional reflecting telescope in existence, the design of which is now known as a Newtonian telescope.

Other Achievements:

He also formulated an empirical law of cooling, studied the speed of sound, and introduced the notion of a Newtonian fluid. This term is used to describe any fluid where the viscous stresses arising from its flow, at every point, are linearly proportional to the rate of change of its deformation over time.

Beyond his work in mathematics, optics and physics, he also devoted a significant amount of time studying Biblical chronology and alchemy, but most of his work in these areas remained unpublished until long after his death.

So what did Isaac Newton discover? Theories that would dominate the fields of science, astronomy, physics and the natural world for centuries to come. His ideas would go on to influence such luminaries as Joseph-Louis Lagrange and Albert Einstein, the latter of whom is the only scientists believed to have left a comparable legacy.

We have written many interesting articles about Sir Isaac Newton here at Universe Today. Here’s Who was Sir Isaac Newton?, What did Isaac Newton Invent?, Who Discovered Gravity?, What is Absolute Space?, What is the Gravitational Constant?

There are other resources on the internet if you want to learn more about Isaac Newton. This UK site has some great info on his discoveries. You can also check out the PBS website.

You can also check out Astronomy Cast. Episode 44 Einstein’s Theory of Relativity is particularly interesting.

Sources:

A Snapshot of a Galactic Crash

This image combines NASA/ESA Hubble Space Telescope observations with data from the Chandra X-ray Observatory. As well as the electric blue ram pressure stripping streaks seen emanating from ESO 137-001, a giant gas stream can be seen extending towards the bottom of the frame, only visible in the X-ray part of the spectrum. Credit: NASA, ESA, CXC

Some galaxies shine with a red ghostly glow. Once these galaxies stop forming new stars, they can only host long-lived stars with low masses and red optical colors. Astronomers often call these ghostly galaxies “red and dead.” But the basics behind why some form so quickly is still a mystery.

“It is one of the major tasks of modern astronomy to find out how and why galaxies in clusters evolve from blue to red over a very short period of time,” said lead author Michele Fumagalli from Durham University in a news release. “Catching a galaxy right when it switches from one to the other allows us to investigate how this happens.”

And that’s exactly what Fumagalli and colleagues did.

The team used ESO’s Multi Unit Spectroscopic Explorer (MUSE) instrument mounted on the 8-meter Very Large Telescope. With this instrument, astronomers collect 90,000 spectra every time they look at an object, allowing them to gain a detailed map of the object’s motion through space.

This chart shows the location of the distant galaxy ESO 137-001 in the constellation of Triangulum Australe (The Southern Triangle). This is a rich area of the sky close to the Milky Way, but this galaxy is faint and needs a large telescope to be visible. Credit: ESO, IAU and Sky & Telescope
The location of the distant galaxy ESO 137-001. Credit: ESO / IAU / Sky & Telescope

The target, ESO 137-001, is a spiral galaxy 200 million light-years away in the constellation better known as the Southern Triangle. But more importantly, it’s currently hurtling toward the Norma Cluster and embarking on a grand galactic collision.

ESO 137-001 is being stripped of most of its gas due to a process called ram-pressure stripping. As the galaxy falls into the galaxy cluster, it feels a headwind, much as a runner feels a wind on even the stillest day. At times this can compress the gas enough to spark star formation, but if it’s too intense then the gas is stripped away, leaving a galaxy that’s empty of the material needed to form new stars.

So the galaxy is in the midst of a brilliant transformation, changing from a blue gas-rich galaxy to a red gas-poor galaxy.

The observations show that the outskirts of the galaxy are already completely devoid of gas. Here the stars and matter are more thinly spread, and gravity has a relatively week hold over the gas. So it’s easier to push the gas away.

In fact, dragging behind the galaxy are 200,000 light-year-long streams of gas that have already been lost, making the galaxy look like a jellyfish trailing its tentacles through space. In these streamers, the gas is turbulent enough to compress small pockets of gas and therefore actually ignite star formation.

The center of the galaxy, however, is not yet devoid of gas because the gravitational pull is strong enough to hold out much longer. But it will only take time until all of the galactic gas is swept away, leaving ESO 137-001 red and dead.

Surprisingly the new MUSE observations show the gas trailing behind continues to rotate in the same way that the galaxy does. Furthermore, the rotation of stars at the center of the galaxy remains unhindered by the great fall.

Astronomers remain unsure why as this is only a snapshot of one galactic crash, but soon MUSE and other instruments will pry more out of the cosmic shadows.

The results will be published in the journal Monthly Notices of the Royal Astronomical Society and are available online.

NASA’s Next Exoplanet Hunter Moves Into Development

A conceptual image of the Transiting Exoplanet Survey Satellite. Image Credit: MIT
A conceptual image of the Transiting Exoplanet Survey Satellite. Image Credit: MIT

NASA’s ongoing hunt for exoplanets has entered a new phase as NASA officially confirmed that the Transiting Exoplanet Survey Satellite (TESS) is moving into the development phase. This marks a significant step for the TESS mission, which will search the entire sky for planets outside our solar system (a.k.a. exoplanets). Designed as the first all-sky survey, TESS will spend two years of an overall three-year mission searching both hemispheres of the sky for nearby exoplanets.

Previous sky surveys with ground-based telescopes have mainly picked out giant exoplanets. In contrast, TESS will examine a large number of small planets around the very brightest stars in the sky. TESS will then record the nearest and brightest main sequence stars hosting transiting exoplanets, which will forever be the most favorable targets for detailed investigations. During the third year of the TESS mission, ground-based astronomical observatories will continue monitoring exoplanets identified by the TESS spacecraft.

“This is an incredibly exciting time for the search of planets outside our solar system,” said Mark Sistilli, the TESS program executive from NASA Headquarters, Washington. “We got the green light to start building what is going to be a spacecraft that could change what we think we know about exoplanets.”

“During its first two years in orbit, the TESS spacecraft will concentrate its gaze on several hundred thousand specially chosen stars, looking for small dips in their light caused by orbiting planets passing between their host star and us,” said TESS Principal Investigator George Ricker of the Massachusetts Institute of Technology..

Artistic representations of the only known planets around other stars (exoplanets) with any possibility to support life as we know it. Credit: Planetary Habitability Laboratory, University of Puerto Rico, Arecibo.
Artistic representations of known exoplanets with any possibility to support life. Image Credit: Planetary Habitability Laboratory, University of Puerto Rico, Arecibo.

All in all, TESS is expected to find more than 5,000 exoplanet candidates, including 50 Earth-sized planets. It will also find a wide array of exoplanet types, ranging from small, rocky planets to gas giants. Some of these planets could be the right sizes, and orbit at the correct distances from their stars, to potentially support life.

“The most exciting part of the search for planets outside our solar system is the identification of ‘earthlike’ planets with rocky surfaces and liquid water as well as temperatures and atmospheric constituents that appear hospitable to life,” said TESS Project Manager Jeff Volosin at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “Although these planets are small and harder to detect from so far away, this is exactly the type of world that the TESS mission will focus on identifying.”

Now that NASA has confirmed the development of TESS, the next step is the Critical Design Review, which is scheduled to take place in 2015. This would clear the mission to build the necessary flight hardware for its proposed launch in 2017.

“After spending the past year building the team and honing the design, it is incredibly exciting to be approved to move forward toward implementing NASA’s newest exoplanet hunting mission,” Volosin said.

TESS is designed to complement several other critical missions in the search for life on other planets. Once TESS finds nearby exoplanets to study and determines their sizes, ground-based observatories and other NASA missions, like the James Webb Space Telescope, would make follow-up observations on the most promising candidates to determine their density and other key properties.

The James Webb Space Telescope. Image Credit: NASA/JPL
The James Webb Space Telescope. Image Credit: NASA/JPL

By figuring out a planet’s characteristics, like its atmospheric conditions, scientists could determine whether the targeted planet has a habitable environment.

“TESS should discover thousands of new exoplanets within two hundred light years of Earth,” Ricker said. “Most of these will be orbiting bright stars, making them ideal targets for characterization observations with NASA’s James Webb Space Telescope.”

“The Webb telescope and other teams will focus on understanding the atmospheres and surfaces of these distant worlds, and someday, hopefully identify the first signs of life outside of our solar system,” Volosin said.

TESS will use four cameras to study sections of the sky’s north and south hemispheres, looking for exoplanets. The cameras would cover about 90 percent of the sky by the end of the mission.

This makes TESS an ideal follow-up to the Kepler mission, which searches for exoplanets in a fixed area of the sky. Because the TESS mission surveys the entire sky, TESS is expected to find exoplanets much closer to Earth, making them easier for further study.

In addition, Ricker said TESS would provide precision, full-frame images for more than 20 million bright stars and galaxies.

“This unique new data will comprise a treasure trove for astronomers throughout the world for many decades to come,” Ricker said.

Now that TESS is cleared to move into the next development stage, it can continue towards its goal of being a key part of NASA’s search for life beyond Earth.

“I’m still hopeful that in my lifetime, we will discover the existence of life outside of our solar system and I’m excited to be part of a NASA mission that serves as a key stepping stone in that search,” Volosin said.

Further Reading: NASA

Review: In “Interstellar,” Christopher Nolan Shows He Has The Right Stuff

Mathew McConnaughey wades through an ocean on another planet. This is not a fishing expedition. He is out to save his children and all humanity. Image courtesy Paramount.

Science fiction aficionados, take heed. The highly-anticipated movie Interstellar is sharp and gripping. Nolan and cast show in the end that they have the right stuff. Nearly a three hour saga, it holds your attention and keeps you guessing. Only a couple of scenes seemed to drift and lose focus. Interstellar borrows style and substance from some of the finest in the genre and also adds new twists while paying attention to real science. If a science-fiction movie shies away from imagining the unknown, taking its best shot of what we do not know, then it fails a key aspect of making sci-fi. Interstellar delivers in this respect very well.

Jessica Chastain, the grown daughter of astronaut McConnaughey starts to torch the cornfields. Interstellar viewers are likely to show no sympathy to the ever present corn fields.
Jessica Chastain, the grown daughter of astronaut McConnaughey takes a torch to the cornfields. Interstellar viewers are likely to show no sympathy to the ever present corn fields. Image courtesy Paramount.

The movie begins quite unassuming in an oddly green but dusty farmland. It does not rely on showing off futuristic views of Earth and humanity to dazzle us. However, when you see a farming family with a dinner table full of nothing but variations of their cash crop which is known mostly as feedstock for swine and cattle, you know humanity is in some hard times. McConaughey! Save us now! I do not want to live in such a future!

One is left wondering about what got us to the conditions facing humanity from the onset of the movie. One can easily imagine a couple of hot topic issues that splits the American public in two. But Nolan doesn’t try to add a political or religious bent to Interstellar. NASA is in the movie but apparently after decades of further neglect, it is literally a shadow of even its present self.

Somehow, recent science fiction movies — Gravity being one exception — would make us believe that the majority of American astronauts are from the Midwest. Driving a John Deere when you are 12, being raised under big sky or in proximity to the home of the Wright Brothers would make you hell-bent to get out of Dodge and not just see the world but leave the planet. Matthew McConaughey adds to that persona.

Dr. Kip Thorne made it clear that black is not the primary hue of Black Holes. His guidance offered to Nolan raised science fiction to a new level.
Dr. Kip Thorne made it clear that black is not the primary hue of Black Holes. His guidance offered to Nolan raised science fiction to a new level. Image courtesy Paramount.

We are seemingly in the golden age of astronomy. At present, a science fiction movie with special effects can hardly match the imagery that European and American astronomy is delivering day after day. There is one of our planets that gets a very modest delivery in Interstellar. An undergraduate graphic artist could take hold of NASA imagery and outshine those scenes quite easily. However, it appears that Nolan did not see it necessary to out-do every scene of past sci-fi or every astronomy picture of the day (APOD) to make a great movie.

Nolan drew upon American astro-physicist Dr. Kip Thorne, an expert on Einstein’s General Relativity, to deliver a world-class presentation of possibly the most extraordinary objects in our Universe – black holes. It is fair to place Thorne alongside the likes of Sagan, Feynman, Clarke and Bradbury to advise and deliver wonders of the cosmos in compelling cinematic form. In Instellar, using a black hole in place of a star to hold a planetary system is fascinating and also a bit unbelievable. Whether life could persist in such a system is a open question. There is one scene that will distress most everyone in and around NASA that involves the Apollo Moon landings and one has to wonder if Thorne was pulling a good one on old NASA friends.

Great science fiction combines a vision of the future with a human story. McConaughey and family are pretty unassuming. John Lithgow, who plays grandpa, the retired farmer, doesn’t add much and some craggy old character actor would have been just fine. Michael Cane as the lead professor works well and Cane’s mastery is used to thicken and twist the plot. His role is not unlike the one in Children of Men. He creates bends in the plot that the rest of the cast must conform to.

There was one piece of advice I read in previews of Interstellar. See it in Imax format. So I ventured over to the Imax screening at the Technology Museum in Silicon Valley. I think this advice was half correct. The Earthly scenes gained little or nothing from Imax but once they were in outer space, Imax was the right stuff. Portraying a black hole and other celestial wonders is not easy for anyone including the greatest physicists of our era and Thorne and Nolan were right to use Imax format.

According to industry insiders, Nolan is one of a small group of directors with the clout to demand film recording rather than digital. Director Nolan used film and effects to give Interstellar a very earthy organic feel. That worked and scenes transitioned pretty well to the sublime of outer space. Interstellar now shares the theaters with another interesting movie with science fiction leanings. The Stephen Hawking biography, “The Theory of Everything” is getting very good reviews. They hold different ties to science and I suspect sci-fi lovers will be attracted to seeing both. With Interstellar, out just one full day and I ran into moviegoers that had already seen it more than once.

Where does Interstellar stand compared to Stanley Kubricks works? It doesn’t make that grade of science fiction that stands up as a century-class movie. However, Thorne’s and Nolan’s accounting of black holes and worm holes and the use of gravity is excellent. Instellar makes a 21st Century use of gravity in contrast to Gravity that was stuck in the 20th Century warning us to be careful where you park your space vehicle. In the end, Matthew McConaughey serves humanity well. Anne Hathaway plays a role not unlike Jody Foster in Contact – an intellectual but sympathetic female scientist.

Jessica Chastain playing the grown up daughter of McConaughey brings real angst and an edge to the movie; even Mackenzie Foy playing her part as a child. Call it the view ports for each character – they are short and narrow and Chastain uses hers very well. Matt Damon shows up in a modest but key role and does not disappoint. Nolan’s directing and filmography is impressive, not splashy but one is gripped by scenes. Filming in the small confines of spaceships and spacesuits is challenging and Nolan pulls it off very well. Don’t miss Interstellar in the theaters. It matches and exceeds the quality of several recent science fiction movies. Stepping back onto the street after the movie, the world seemed surprisingly comforting and I was glad to be back from the uncertain future Nolan created.

Mind-blowing Meteor Shower on Mars During Comet Flyby, Say NASA Scientists

We can only imagine what the meteor storm from Comet Siding Spring must have looked like standing on the surface of Mars on October 19, 2014. NASA scientists announced today that the planet experienced an exceptional shower during the comet's flyby, saturating the sky. Source: Stellarium

“Thousands of meteors per hour would have been visible — truly astounding to the human eye.” That’s Nick Schneider’s description of what you and I would have seen standing on Mars during Comet Siding Spring’s close flyby last month. “It would have been really mind-blowing,” he added. Schneider is instrument lead for MAVEN’s Imaging Ultraviolet Spectrograph (IUVS).

He and a group of scientists who work as lead investigators for instruments on the MAVEN and  Mars Reconnaissance Orbiter (MRO) spacecraft shared the latest results from the comet flyby during a media teleconference earlier today. There were many surprises. Would we expect anything less from a comet?

Here’s a summary of the results:

A very dusty ice ball – The comet’s dust tail and the amount of dust in its coma were much larger than expected, prompting Jim Green, director of NASA’s Planetary Science Division in Washington,  to remark: “It makes me very happy we hid them (the spacecraft) on the backside of Mars. That really saved them.” Siding Spring dumped several tons of fine dust into the Martian atmosphere prompting a spectacular meteor shower and possibly causing a yellow, twilight afterglow above the Curiosity landing site from vaporizing sodium atoms contained in the minerals. That, and dust in the mid-levels of the atmosphere at the time contributed to the rover’s difficulty in getting good photos of the comet itself. Scientists are still examining the images.

MAVEN's Ultraviolet Imaging Spectrograph (IUVS) uses limb scans to map the chemical makeup and vertical structure across Mars' upper atmosphere. It detected strong enhancements of magnesium and iron from ablating incandescing dust from Comet Siding Spring. Credit: NASA
MAVEN’s Ultraviolet Imaging Spectrograph (IUVS) uses limb scans to map the chemical makeup and vertical structure across Mars’ upper atmosphere. It detected strong enhancements of magnesium and iron from ablating incandescing dust from Comet Siding Spring. Credit: NASA
I'm not big into graphs either, but check out the heavy metal drama in this. On the left is the "before" scan from MAVEN's IUVS instrument; on the right, during the comet's close approach. The spike in magnesium from vaporizing comet dust is impressive. Ionized magnesium is the strongest spike with neutral and ionized iron on the left in smaller amounts. Both elements are common in meteorites as well as on Earth. Credit: NASA
I’m not big into graphs either, but check out the heavy metal drama going on here. On the left is the “before” scan from MAVEN’s IUVS instrument; on the right, during the comet’s close approach. The spike in magnesium from vaporizing comet dust is impressive. Ionized magnesium is the strongest spike with neutral and ionized iron on the left in smaller amounts. Both elements are common in meteorites as well as on Earth. Credit: NASA
Profiles showing spikes in the amounts of eight different metals detected in Mars' atmosphere during the flyby by MAVEN's Neutral Gas and Ion Mass Spectrometer (NGIMS). The emissions faded with a short time. Credit: NASA
Profiles showing spikes in the amounts of eight different metals over time detected in Mars’ atmosphere by MAVEN’s Neutral Gas and Ion Mass Spectrometer (NGIMS). The emissions faded within a short time, but chemicals from the comet will continue to interact with the Martian atmosphere over time. Credit: NASA

Chemistry of Mars’ atmosphere changed – Dust vaporized in the intense meteor shower produced a striking increase in the amount of magnesium, iron and others metals in Mars’ upper atmosphere. “We were pressed back in our chairs,” said Mike Schneider. The bombardment created a temporary new layer of comet-tainted air and may have acted as condensation nuclei for the formation of high-altitude clouds. MAVEN’s Neutral Gas and Ion Mass Spectrometer (NGIMS) recorded huge spikes in the levels of eight different metals during the comet’s passage and then trailed off a day or so later. “They came to MAVEN as a free sample from no less than an Oort Cloud comet,” said Mehdi Benna, instrument scientist for MAVEN’s Neutral Gas and Ion Mass Spectrometer.

The MARSIS instrument on the Mars Express is a ground penetrating radar sounder used to look for subsurface water and ice. It can also make soundings of the ionosphere. It was used to see the new ionospheric layer formed by vaporizing comet dust on October 19th. Credit: ESA
The MARSIS instrument on the Mars Express is a ground penetrating radar sounder used to look for subsurface water and ice. It can also make soundings of the ionosphere. It was used to see the new ionospheric layer formed by vaporizing comet dust on October 19th. Credit: ESA
The Mars Express radar probed the ionosphere (upper atmosphere) at three different times. At top, before the comet arrived; middle, 7 hours later after the comet's closest approach and bottom, hours later after the comet had departed. The middle graph shows a strong signal (blue horizontal bar) from the creation of newly-ionized layer of the planet's lower atmosphere from hot, fast-moving comet dust. Credit: ESA
The Mars Express radar probed the ionosphere (upper atmosphere) at three different times. At top, before the comet arrived; middle, 7 hours later after the comet’s closest approach and bottom, hours later after the comet had departed. The middle graph shows a strong signal (blue horizontal bar) from the creation of a newly-ionized layer of the planet’s lower atmosphere from hot, fast-moving comet dust. Credit: ESA

 

Flaming comet dust creates new ionospheric layer – Comet dust slamming into the atmosphere at 125,000 mph (56 km/sec) knocked electrons loose from atoms in the thin Martian air  50-60 miles (80-100 km) high, ionizing them and creating a very dense ionization layer in the planet’s lower ionosphere seven hours after the comet’s closest approach. Normally, Mars ionosphere is only seen on the dayside of the planet, but even when the MARSIS instrument on Mars Express  beamed radio waves through the atmosphere on the nightside of the planet, it picked up a very strong signal.

54 red-filtered images of the comet's nucleus-coma taken by the MRO's HiRISE camera show changes in the flow of material leaving the comet. Credit: NASA
54 red-filtered, false-color images of the comet’s nucleus-coma taken by the MRO’s HiRISE camera show changes in the flow of material leaving the comet. Based on the photos, the comet’s nucleus spins once every 8 hours. Credit: NASA
The five closest photos made with the HiRISE camera show the combined light of the nucleus and coma. Scale is 140-meter per pixel at top and 177-meters at bottom. Scientists will further process these images to separate the nucleus from the coma. Credit: NASA
The five closest photos made with the HiRISE camera show the combined light of the nucleus and coma. Scale is 140-meter per pixel at top and 177-meters at bottom. Scientists will further process these images to separate the nucleus from the coma. Credit: NASA

Nucleus spins once during your work day – Comet Siding Spring’s icy core spins once every 8 hours and its irregular shape causes strong variations in the comet’s brightness. The comet’s size appears less certain  – at least for the moment – with estimates anywhere between a few hundred meters to 2 km (1.2 miles). More analysis on images taken by MRO’s HiRISE camera should narrow that number soon.

CRISM photo and spectrum of Comet Siding Spring. The spectrum is "flat", indicating we're seeing sunlight reflected off comet dust. The intriguing color variations in the image tell of dust particles of varying size leaving the nucleus. Credit: NASA
CRISM photo and spectrum of Comet Siding Spring. The spectrum is “flat”, indicating we’re seeing ordinary sunlight reflecting off comet dust. The intriguing color variations in the image tell us the comet’s spewing dust particles of many sizes. Credit: NASA

Dust motes of many sizes – Color variations across Siding Spring’s coma seen by Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) indicate it’s releasing dust particles of different sizes – big and little.

The scientists involved in the encounter couldn’t be happier with how the instruments functioned and the amount of hard data returned. Said Jim Green: “We are so lucky to observe this once-in-a-lifetime event.” How true when you consider that it takes about 8 million years for a comet from the Oort Cloud, that vast reservoir of frozen comets  extending nearly a light year from the Sun, to get here in the first place.  Nick Schneider put it another way:

“Not only is this a free sample of the Oort Cloud in Mars’ atmosphere, but it gives us a chance to learn more about Mars itself.”

If you’d like to listen in to the hour-long teleconference at any time, it’ll be up for the next week or so HERE.

A Comet’s Tale – Rosetta’s Philae, Five Days from Touchdown

Rosetta, the scientific mission to explore a comet's surface. "Ambition", a short Sci-Fi film, set in the near future, and Rosetta, the children's fable, to encourage the next generations to undertake on the great adventures still to come. (Photo Credits: ESA, Platige Image, ESA Communications)

In the recently released Rosetta short film called “Ambition”, the master begins a story to his apprentice – “Once upon a time.” The apprentice immediately objects to his triteness. But he promises that it is worth the slight tribulation. Who could have imagined ten years ago that Rosetta would become so successful in two such contrasting approaches to telling a tale.

The Rosetta mission is part franchise and part scientific mission. In five days, Rosetta will reach a crossroad, a point of no return as epic as moments in Harry Potter or Lord of the Rings. A small mindless little probe called Philae will be released on a one-way trip to the surface of a comet. Win or lose, Philae will live on in the tale of a comet and a mission to uncover the mysteries of our planet’s formation.

ESA did not promise a good mission as Aidan Gillen promises a good story in Ambition. A space mission is never put in terms of a promise but rather it is thousands of requirements and constraints that formulate a mission plan and a spacecraft design. The European Space Agency put 1 billion Euros ($1.3 billion) to work and did so in what now looks like one of the greatest space missions of the first century of space exploration.

The Rosetta mission is actually two missions in one. There is the comet chaser, the orbiter – Rosetta and then the lander Philae. The design of Rosetta’s objectives is some part, probably in large part, was conceived by dismissing the presence of Philae. Make a space probe to a comet that just orbits the small body. Select your scientific instrumentations accordingly. Now add a small lander to the mission profile that will do something extraordinary – what Rosetta cannot do with its instrumentation. Finally, make sure that Rosetta has everything needed to support Philae’s landing on a comet.

Here is what they have as the game plan on November 12th (the sequence of events begins while its still November 11th in the Americas). These two times are absolutely non- trivial. They are finely tuned to a timepiece called  67P/Churyumov–Gerasimenko. If calculations were made in error, then Philae’s ultimate fate is unknown. Start exactly on time and Philae will be given the best chance at making a successful  touchdown on the comet.

Separation of Philae from Rosetta:   09:03 GMT (10:03 CET)

Touchdown on the comet:                    16:02 GMT (17:02 CET).

During this time, comet  67P/Churyumov–Gerasimenko will complete over half a rotation on its axis. To be exact, it will rotate 56.2977% of a full rotation. Comet 67P will have its back turned towards Rosetta as it holds the diminutive Philae for the last time and releases Philae for the first and only time.

Now that the ESA, with help from the graphic artists from Platige Image from Poland, has released something entertaining for the science fiction minded among us, they have again released a next episode in their children’s fable of Rosetta and Philae (video below). This cartoon of the final moments of Rosetta and Philae together preparing for the descent which could well be the final moments of Philae.

Philae could fail, crack like an egg on a sharp rock or topple over a cliff or into a crevasse on the surface of 67P. What happens to Philae will make for a Grimm’s fairy tale ending or something we would all prefer. In either case, the ESA is using graphic arts and storytelling to inspire the next generations to join in what our JFK called “great adventures of all time” [ref].

Through a contest something NASA and JPL have used several times to involve the public, the ESA asked the public to come up with a name for the landing site, site J. Out of the thousands of entries, 150 people suggested the name Agilkia [ref]. Alexandre Brouste from France, the designated winner, has been invited to watch the landing activities at Rosetta’s mission control in Darmstadt, Germany. It follows from the Eqyptian theme of the mission’s two probes. “Rosetta” comes from the clay tablet discovered in the 1800s that led to the deciphering of Egyptian hieroglyphics. Philae” is a island on the Nile which held magnificent Eqyptian temples. With the operation  of the Aswan dam starting in 1902, the island of Philae was repeatedly flooded and the temple was at risk. UNESCO beginning in 1960 started a project to save the islands historic structures. They were all moved to a nearby Nile island called Agilkia [related U.T. article]. This becomes a part of the Rosetta story – a lander named Philae in reference to the obelisks used along with the Rosetta stone to decipher Eqyptian writings, departing its mother ship on a short but critical voyage to a final resting place, the landing site now called Agilkia.

Upon landing, a landing confirmation signal is expected from Philae via Rosetta at about 8:02 AM PST (11:02 AM EST, 17:02 Central European Time). Alexandre Brouste of France, the designated winner of the landing site naming contest will be in Darmstadt, Germany in mission control to watch the landing unfold with the Rosetta engineers and scientists. Surely, millions of citizens of the European Union and people worldwide will be watching via the World Wide Web.

The timeline and events to unfold as Philae, the lander is released from Rosetta, the comet orbiter. (Illustration Credit: ESA)
The timeline and events to unfold as Philae, the lander is released from Rosetta, the comet orbiter. (Illustration Credit: ESA)

Previous Rosetta and Philae articles at Universe Today

Rosetta’s Philae Lander: A Swiss Army Knife of Scientific Instruments

Why Watch ESA Rosetta’s Movie ‘Ambition’? Because We Want to Know What is Possible