Interview with Colin Pillinger

Image credit: Beagle 2
Colin Pillinger is married and has two children. He lives on a small farm in Cambridgeshire, where his livestock keep him busy out of working hours. He first became interested in ‘space science’ by reading Dan Dare comics and listening to ‘Journey Into Space’ on the radio.

“The loss of Beagle-2 I would say was very frustrating to everyone who worked on the project including myself, because the craft carried the first instruments down onto the Martian surface that would actually look for Carbon based organisms, as apposed to carrying out a chemical analysis of the Martian soil by adding liquid nutrients, which is what the Label Release Experiment did on the Vikings landers back in 1976,” explained Professor Pillinger.

2004 has truly been ‘The year of Mars’ with the European Space Agency’s Mars Express doing remarkable science in Martian orbit, while sending back highly detailed images of the planet, and with the successful landing of the two NASA/JPL rovers Spirit and Opportunity in January which have done good geological science leading to the discovery that a huge quantity of water once flowed on the red planet.

“Finding out that a large amount of water existed on Mars in the past was good news because it brings the possibility of some form of life on the planet that bit closer,” explained Colin. “Meteorites from Mars that have landed on Earth show clear evidence that conditions appropriate to life did exist on the red planet, including in the recent past.

“However, features in the meteorites which have been described as nanofossils are highly controversial. Unfortunately, we cannot be sure that organic matter found in the meteorites is the remnant of organisms that lived on Mars and not due to contamination on Earth. We need to repeat the experiments on rocks that never left Mars,” he continued.

A short time ago I talked to Sir Patrick Moore about the best chance of finding life in the solar system, and I posed this question to Professor Pillinger as well. In our interview, Sir Patrick had said, “I believe our best chance of finding life is on the planet Mars. We now know that a lot of water once existed on this planet sometime in the past, and the latest surface rovers (Spirit and Opportunity), along side orbiting space probes like Mars Express, have shown that the Martian conditions are more favorable for life to evolve their today than at any time in the past. If the conditions are right, life will always find a way to exist.”

Prof. Pillinger replied “The fact that Mars Express has also confirmed the existence of methane in the thin Martian atmosphere, is interesting too.

“There have been two independent astronomical observations that first detected the presence of methane while Mars Express just confirmed it, and we now know that the amount of this gas is more than can be accounted for by volcanic activity.”

On Earth, there are many creatures, large and small, that produce methane. The simplest biological sources, including peat bogs, rice fields and ruminant animals (cows, sheep, etc.), continuously supply fresh gas to replace that destroyed by oxidation.

Methane also has a very short lifetime on Mars because of the oxidizing nature of the atmosphere, so its presence would indicate a replenishing source, which may be life, even if it is buried beneath the surface. If this methane exists, the Mars Express Orbiter has an instrument which should be able to detect it in the atmosphere.

“The Beagle-2 lander would have looked for signatures of life on Mars, whether long-dead or still-living, by measuring the ratio of two different types of carbon in the rock,” explained Prof. Pillinger. “Biological processes on Earth favor the lighter isotope of carbon, carbon-12, over the heavier carbon-13. Hence, a high carbon-12 to carbon-13 ratio is taken as evidence of life and has been found in rocks up to 4000 million years old, even where geological processing has occurred.”

Dr. Gilbert V. Levin, an experimenter with the original 1976 Viking Mission to Mars has been following this methane discovery with great interest. He has been advocating for years that Viking did find evidence of life on Mars with the Labeled Release life detection experiment, but other scientists are still skeptical.

I asked Colin if the discoveries by Spirit and Opportunity in 2004, or the recent discovery of methane supported Dr. Levin’s findings.

“I have heard of Dr. Levin. I think it is a firm understanding among planetary scientists that the Viking life investigation experiment only detected a chemical reaction rather than finding life on Mars itself. There is no point in harking on about the past, it’s time to move on and look for the real evidence of the carbon-based organisms that may exist on Mars today. That is where the Beagle 2 experiment differed from that of the Viking landers.”

Is there any other evidence that life may exist on the red planet, I asked? “Yes, meteorites from Mars that have landed on Earth show clear evidence that conditions appropriate to life did exist on the planet, including in the recent past, unfortunately, we cannot be sure that organic matter found in the meteorites is the remnant of organisms that lived on Mars and not due to contamination on Earth. We need to repeat the experiments on rocks that never left the Red Planet.

“At the moment there is no new Beagle Mars Lander project; however, I think this is an exciting time to look for life on Mars, and Beagle was well equipped to try and find it, which is why it has been very frustrating for my team and myself. I think that a new British Beagle lander should be built at this time to go to Mars and look for signs of life on the planet’s surface.”

By Science Correspondent Richard Pearson

What’s Up This Week – Nov 22 – 28, 2004

Monday, November 22 – How about taking time to study a bit of astronomy this morning before a busy work week begins? Before dawn, ultra-bright Venus commands the ecliptic plane. Just above it, blue star Spica and mighty Jupiter capture attention and dim, red Mars is below Venus. This is a wonderful sight for just the unaided eye, but why not try a challenge this morning? All it will require is binoculars and clear sky! For viewers in both hemispheres, (40 degrees and below) the time is perfect to locate Comet C/2003 K4 LINEAR as it slides just slightly south of visible star Beta Hydra. At an estimated magnitude of 5, it will be a beauty for the Southern Hemisphere and a challenge for the North!

Tonight’s lunar feature can be spotted in binoculars, but needs a telescope to be studied. The Riphaeus Mountains will appear to the southwest of Copernicus. Highlighted by the bright ring of Euler, the Riphaeus Mountains under high power show a variety of isolated hills and sharp peaks which may have been the original crater walls of Mare Cognitum before having been filled with lava flow. Northeast of this range is an area with a smooth floor on the border of Oceanus Procellarum. It is here that Surveyor 3 landed on April 19, 1967. After having bounced three times, the lunar probe came to rest on a smooth slope in a sub-telescopic crater. As its on-board television monitors watched, Surveyor 3 deployed the “first of its kind” miniature power shovel and dug to a depth of 18 inches. The revelation of sub-soil material and clean-cut lines allowed scientists to come to the conclusion that the loose lunar soil was capable of compaction. Watching as Surveyor 3 pounded its shovel against the surface, the tiny “dents” it produced answered the crucial question – the surface of a mare would support the landing of a spacecraft and subsequent exploration by astronauts.

In the mood to stay up late tonight? Then wait until well past midnight until Orion has risen well in the sky and let’s try for another comet despite the Moon. Comet C/2004 Q2 (Machholz) is visible to larger binoculars, but better achieved in telescopes for northern viewers 40 degrees and below. At around magnitude 8, it will appear on the Columba/Caelum border. Viewers in both hemispheres should enjoy this one!

Tuesday, November 23 – The first photograph of a meteor shower was taken on this day in 1885 in Prague, Czechoslovakia but no picture can rival the beauty of the predawn skies as Venus once again dominates the scene. While lovely Spica and Jupiter try to steal the show, try to ignore them as it’s time to start observing Mars (right below Venus) and watch in the coming days as they appear closer and closer together.

Weather satellite Tiros II was launched on this day in 1960. Carried to orbit by a three-stage Delta rocket, the “Television Infrared Observation Satellite” was about the size of a barrel, testing experimental television techniques and infrared equipment. Operating for 376 days, Tiros II sent back thousands of pictures of Earth’s cloud cover and was successful in its experiments to control orientation of satellite spin and infrared sensors. Oddly enough, a similar mission – Meteosat1- also became the first satellite put into orbit in 1977 on this day by the European Space Agency. Where is all this leading? Why not try observing satellites on your own! Thanks to a wonderful tool from NASA you can be alerted by email whenever a bright satellite makes a pass for your specific area. It’s fun!

Tonight’s lunar feature will be bright, medium-sized class one crater, Artistarchus. On the terminator tonight north of Keplar, this dazzling feature can sometimes be seen by the naked eye and with no problem in binoculars. For telescopic viewers, Aristarchus will offer up a splendid challenge as you are encouraged to look for a thin, bright thread that curls away from it. Named Schroter’s Valley, it is a sinous rille and the largest of its kind. It may have once been a lava drainage channel, for it bears similarities with our own terrestrial volcanic features.

Wednesday, November 24
Heads up! There will an occulation of a bright star tonight by an asteroid. Visible from the NE to SW United States, Asteroid 860 Ursina will occult HIP 11395 (magnitude 7). For more details, click here for an IOTA locater chart and prediction times.

Comet C/2001 T4 (NEAT) will make its closest approach to Earth at a distance of 8.190 AU. Dry fact or an observable reality? Comet T4 is indeed very visible to the northern hemisphere, but it is not for the faint of heart. Right now it is holding around a magnitude 11 and is cutting its way across the Draco/Bootes border, making it a prime target for early morning viewers when the Moon is as low as it can possibly be. Requiring at least 12.5 inches of aperture, T4 will closely resemble a small, out-of-focus globular cluster since the Moon will toast any indication of coma. Are you up to that kind of challenge? I dare ya…

Tonight’s highlighted lunar feature can be seen in binoculars but best viewed with a telescope. Located in the southwest quadrant and on the terminator just south of Shickard, crater Wargentin is most unique. Once upon a time, it was a very normal crater and had been that way for hundreds of millions of years – then it happened. Either a fissure opened in its interior, or the meteoric impact that formed it caused molten lava to begin to rise. Oddly enough, Wargentin’s walls were without large enough breaks to allow the lava to escape and it continued to fill the crater to the rim. Often referred to as “the Cheese”, enjoy Wargentin tonight for its unusual appearance!

Thursday, November 25 – Ready to aim for a bullseye? Then tonight as darkness completely falls, go have a look at the Moon. To the right of it will be the M45, or the Pleiades star cluster. Just below it you will note bright, reddish star, Aldeberan. Set your eyes, scopes or binoculars there and let’s look into the “eye” of the Bull.

Known early on as “Al Dabaran”, or “the Follower”, Alpha Tauri it took its name for the fact that it appears to follow the Pleiades across the sky. In Latin it was “Stella Dominatrix”, yet the old English knew it as “Oculus Tauri”, or very literally the “eye of Taurus”. No matter which ancient astronomy lore we explore, there is reference to Aldeberan. As the 13th brightest star in the sky, it almost appears from Earth to be a member of the V-shaped Hyades star cluster, but its association is merely coincidental since it is about twice as close to us as the cluster. In reality, Aldeberan is really on the small end as far as K5 stars go and like many other orange giants, could possibly be a variable. Aldeberan is also known to have five close companions, but they are faint and highly difficult to observe with backyard equipment. At a distance of approximately 68 light years away, Alpha is only about 40 times larger than our own Sun and approximately 125 times brighter. To get a grasp on that size, think of it as being about the same size as the Earth’s orbit! Because of its position along the ecliptic, Aldeberan is one of the very few stars of first magnitude that can be occulted by the Moon.

And speaking of Moon, let’s explore tonight’s lunar feature – Galileo. It is a challenge for binoculars to spot this feature, but telescopes of any size capable of higher power will find it easily on the terminator to the west, northwest section of the Moon. Set in the smooth sands of Oceanus Procellarum, Galileo is a very tiny, eye-shaped crater and has a soft rille that accompanies it. It was named for the very man who first viewed and contemplated the Moon through a telescope. No matter what lunar resource you chose to follow, all agree that giving such an insignificant crater a great name like Galileo is unthinkable! For those of you familiar with some of the outstanding lunar features, read this account of Galileo’s life and just look at how many spectacular craters were named for people he supported! We cannot change the names of lunar cartography, but we can remember Galileo’s many accomplishments each time we view this crater.

Friday, November 26 – Today is the fifth anniversary of the discovery of SAU 005 & 008 labeled “Mars Meteorites”. These meteorites are known to be of Mars origin because of gases preserved in the glassy material of their interior. They were hurled into space some 600,000 years ago when a probable asteroid impact on Mars tossed them high enough to escape the planet’s gravity and were captured by our gravity thousands of years later. These are just 2 of the 32 meteorites found on Earth positively classed from their chemical compositions to be of Martian origin.

Comet 32P Comas Sola will make its closest approach to the Earth at a distance of 1.237 AU, but is it visible? The answer is yes. At around magnitude 13, Comas Sola is within the range of large aperture telescopes, but viewing will be difficult tonight thanks to the full Moon. Now cruising the border of Cetus and Aries, 32P can be found very near Mu Cetus. If you cannot spot it tonight, try in just a few days when the later rise of the Moon will provide darker skies.

Since it will be bright tonight, why don’t we try doing something a little different with an astronomical twist? Earlier in the week we discussed watching satellites, so how about if we learn how and when to locate the International Space Station! It’s easy to discover visible passes of the ISS using tools like this link provides, and even more fun to watch them. There may be a pass that will occur tonight in your area, and you might have to wait a few days, but the tool is now in your hands to predict the sightings. If you are new to the astronomy game, it may take a few times before the numbers that determine the height of the pass make sense from where you view, but don’t be discouraged if you don’t spot it right away. A rule of thumb is an altitude value of 10 means it will be very low on the horizon, while one of 90 means it will pass directly overhead. It’s very exciting to follow with binoculars because you can make out a certain amount of detail and those talented enough to “track” with a telescope will see even more. Even if you just watch with your eyes, it’s still a wonderful event that folks of all ages enjoy. Happy Hunting!

Tonight’s full Moon is also known as the “Frost Moon” and there is little doubt about how its name came to be! For those of you interested in viewing lunar features tonight, libration will be favourable to study a collection of shallow, dark craters known as Mare Australe. Located on the southeastern limb, this large binocular and telescopic object is well-worth locating because it isn’t always visible to the degree it will be tonight.

Saturday, November 27 – Tonight Uranus is at opposition. No, this doesn’t mean the planet is causing an altercation in the heavens or joining a political party. It just means that Uranus has now reached the point in its orbit where its celestial longitude is precisely 180 degrees from that of the Sun. Here’s a tip: planets that have reached opposition are visible all night long!

Tonight, rather than adventure on the lunar surface, let’s turn our eyes to the far north and explore the constellation of Cassiopeia. Almost everyone is familiar with the legend of Cassiopeia and how the Queen came to be bound in her chair, destined for an eternity to turn over and over in the sky, but did you know that Cassiopeia holds a wealth of double stars and galactic clusters? Seasoned sky watchers have long been familiar with this constellation’s many delights, but let’s pretend that not everyone knows where they are all at and tonight let’s begin our exploration of this Cassiopeia with a two of its primary stars.

Looking much like a flattened “W” the southern-most bright star is Alpha. Also known as Schedar, this magnitude 2.2 spectral type K star, was once suspected of being a variable, but no changes have been detected in modern astronomy. Binoculars will reveal its orange/yellow coloring, but a telescope is needed to bring out its unique features. In 1781, Sir William Herschel discovered a 9th magnitude companion star and our modern optics easily separate the blue/white component’s distance of 63″. A second, even fainter companion at 38″ is mentioned in the list of double stars and even a third at 14th magnitude was spotted by S.W. Burnham in 1889. All three stars are optical companions only, but make 150 to 200 light year distant Schedar a delight to view!

Just north of Alpha is the next destination for tonight… Eta Cassiopeiae. Discovered by Sir William Herschel in August of 1779, Eta is quite possibly one of the most well-known of binary stars. The 3.5 magnitude primary star is a spectral type G, meaning it has a yellowish color much like our own Sun. It is about 10% larger than Sol and about 25% brighter. The 7.5 magnitude secondary (or B star) is very definitely a K-type, metal poor, and distinctively red. In comparison, it is half the mass of our Sun, crammed into about a quarter of its volume and around 25 times dimmer. In the eyepiece, the B star will angle off to the northwest, providing a wonderful and colorful look at one of the season’s finest!

Sunday, November 28 – Why not step outside this morning before dawn and have a look at Mars just below Venus on the horizon? This would be a fitting way to celebrate the 40th anniversary of the Mariner 4 launch. Mariner 4 gave us our first “up close and personal” looks of the planet’s surface as it beamed back 22 television pictures of Mars’ barren, dusty red surface. As we look at Mars this morning, think of all the changes that have occurred in its exploration in just 40 years!

Heads up for this evening! In a line from Greenland, through Canada, to the northwest United States, Asteroid 80 Sappho will occult HIP 19229 (7.9 magnitude). For the northeast to southwest United States, 64 Angelina will occult SAO093069(b) (magnitude 11.3) and then a bit later take out SAO093069(a) (magnitude 10) for the southeast/southwest United States. Be sure to click on the links for appropriate times and finder charts supplied by IOTA.

Thanks to just a slightly later rise of the Moon, let’s return again to Cassiopeia and start first by exploring the central most bright star, Gamma. At approximately 100 light years away, Gamma is a very unusual star. Once thought to be a variable, this particular star has been known to go through some very radical changes with its temperature, spectrum, magnitude, color and even diameter! Gamma is also a visual double star, but the 11 magnitude companion is highly difficult to perceive so close (2.3″) from the primary.

Four degrees southeast of Gamma is our marker for this starhop, Phi Cassiopeiae. By aiming binoculars or telescopes at this star, it is very easy to locate an interesting open cluster, NGC457, because they will be in the same field of view. This bright and splendid galactic cluster has received a variety of names over the years because of its uncanny resemblance to a figure. Some call it an “Angel”, others see it as the “Zuni Thunderbird”, I’ve heard it called the “Owl” and the “Dragonfly”, but perhaps my most favourite is the “E.T. Cluster”, As you view it, you can see why! Bright Phi and HD 7902 appear like “eyes” in the dark and the dozens of stars that make up the “body” appear like outstretched “arms” or “wings”. (For E.T. fans? Check out the red “heart” in the center.)

All this is very fanciful, but what is the NGC457, really? Both Phi and HD 7902 may not be true members of the cluster. If magnitude 5 Phi were actually part of this grouping, it would have to have a distance of approximately 9300 light years, making it the most luminous star in the sky, far outshining even Rigel! To get a rough of idea of what that means, if we were to view our own Sun from this far away, it would be no more than magnitude 17.5. The fainter members of the NGC457 comprise a relatively “young” star cluster that spans about 30 light years across. Most of the stars are only about 10 million years old, yet there is 8.6 magnitude red supergiant in the center.

No matter what you call it, the NGC457 is an entertaining bright cluster that you will find yourself returning to again and again. Enjoy!

Until next week? Keep looking up and enjoying the wonders of the night sky! Wishing you clear skies and light speed…

~Tammy Plotner

Private Spaceflight Legislation Passes

The US House of Representatives approved legislation on Saturday that would make regulations easier for companies looking to provide rides on private spacecraft. The vote for HR 5382 passed 269-120, which allows it to now go on for Senate approval, and finally to be signed by the President. This bill would streamline space tourism, allowing passengers to fly at their own risk, instead of forcing operators to take on excessive risk and insurance.

Swift Launches to Search for Cosmic Explosions

NASA’s Swift satellite successfully launched today aboard a Boeing Delta 2 rocket at 12:16 p.m. EST from Launch Complex 17A at the Cape Canaveral Air Force Station, Fla. The satellite will pinpoint the location of distant yet fleeting explosions that appear to signal the births of black holes.

About 80 minutes after launch, the spacecraft was successfully separated from the Delta second stage. It has also been confirmed that the solar arrays are properly deployed.

“It’s a thrill that Swift is in orbit. We expect to detect and analyze more than 100 gamma-ray bursts a year. These are the most powerful explosions in the universe, and I can’t wait to learn more about them,” said Swift Principal Investigator Dr. Neil Gehrels, at NASA’s Goddard Space Flight Center, Greenbelt, Md.

Each gamma-ray burst is a short-lived event, lasting only a few milliseconds to a few minutes, never to appear again. They occur several times daily somewhere in the universe, and Swift should detect several weekly.

Swift, a mission with international participation, was designed to solve the 35-year-old mystery of the origin of gamma-ray bursts. Scientists believe the bursts are related to the formation of black holes throughout the universe – the birth cries of black holes.

To track these mysterious bursts, Swift carries a suite of three main instruments. The Burst Alert Telescope (BAT) instrument, built by Goddard, will detect and locate about two gamma-ray bursts weekly, relaying a rough position to the ground within 20 seconds. The satellite will swiftly re-point itself to bring the burst area into the narrower fields of view of the on-board X-ray Telescope (XRT) and the UltraViolet/Optical Telescope (UVOT). These telescopes study the afterglow of the burst produced by the cooling ashes that remain from the original explosion.

The XRT and UVOT instruments will determine a precise arc-second position of the burst and measure the spectrum of its afterglow from visible to X-ray wavelengths. For most of the bursts detected, Swift data, combined with complementary observations conducted with ground-based telescopes, will enable measurements of the distances to the burst sources.

The afterglow phenomenon can linger in X-ray light, optical light, and radio waves for hours to weeks, providing detailed information about the burst. Swift will check in on bursts regularly to study the fading afterglow, as will ground-based optical and radio telescopes. The crucial link is having a precise location to direct other telescopes. Swift will provide extremely precise positions for bursts in a matter of minutes.

Swift notifies the astronomical community via the Goddard-maintained Gamma-ray Burst Coordinates Network. The Swift Mission Operations Center, operated from Penn State’s University Park, Pa., campus, controls the Swift observatory and provides continuous burst information.

“Swift can respond almost instantly to any astrophysical phenomenon, and I suspect that we’re going to be making many discoveries which are currently unpredicted,” said Swift Mission Director John Nousek, Penn State professor of astronomy and astrophysics.

Goddard manages Swift. Swift is a NASA mission with the participation of the Italian Space Agency (ASI) and the Particle Physics and Astronomy Research Council in the United Kingdom.

Swift was built through collaboration with national laboratories, universities and international partners, including General Dynamics, Gilbert, Arizona; Penn State University; Los Alamos National Laboratory, New Mexico; Sonoma State University, Rohnert Park, Calif.; Mullard Space Science Laboratory in Dorking, Surrey, England; the University of Leicester, England; ASI-Malindi ground station in Africa; the ASI Science Data Center in Italy; and the Brera Observatory in Milan, Italy.

For more information about Swift on the Internet, visit:

http://www.nasa.gov/swift and http://swift.gsfc.nasa.gov

Original Source: NASA News Release

Supermassive Black Holes Early On

NASA’s Chandra X-ray Observatory has obtained definitive evidence that a distant quasar formed less than a billion years after the Big Bang contains a fully-grown supermassive black hole generating energy at the rate of twenty trillion Suns. The existence of such massive black holes at this early epoch of the Universe challenges theories of the formation of galaxies and supermassive black holes.

Astronomers Daniel Schwartz and Shanil Virani of the Harvard-Smithsonian Center for Astrophysics in Cambridge, MA observed the quasar, known as SDSSp J1306, which is 12.7 billion light years away. Since the Universe is estimated to be 13.7 billion years old, we see the quasar as it was a billion years after the Big Bang. They found that the distribution of X-rays with energy, or X-ray spectrum, is indistinguishable from that of nearby, older quasars. Likewise, the relative brightness at optical and X-ray wavelengths of SDSSp J1306 was similar to that of the nearby group of quasars. Optical observations suggest that the mass of the black hole is about a billion solar masses.

Evidence of another early-epoch supermassive black hole was published previously by a team of scientists from the California Institute of Technology and the United Kingdom using the XMM-Newton X-ray satellite. They observed the quasar SDSSp J1030 at a distance of 12.8 billion light years and found essentially the same result for the X-ray spectrum as the Smithsonian scientists found for SDSSp J1306. Chandra’s precise location and spectrum for SDSSp J1306 with nearly the same properties eliminate any lingering uncertainty that precocious supermassive black holes exist.

“These two results seem to indicate that the way supermassive black holes produce X-rays has remained essentially the same from a very early date in the Universe,” said Schwartz. “This implies that the central black hole engine in a massive galaxy was formed very soon after the Big Bang.”

There is general agreement among astronomers that X-radiation from the vicinity of supermassive black holes is produced as gas is pulled toward a black hole, and heated to temperatures ranging from millions to billions of degrees. Most of the infalling gas is concentrated in a rapidly rotating disk, the inner part of which has a hot atmosphere or corona where temperatures can climb to billions of degrees.

Although the precise geometry and details of the X-ray production are not known, observations of numerous quasars, or supermassive black holes, have shown that many of them have very similar X-ray spectra, especially at high X-ray energies. This suggests that the basic geometry and mechanism are the same for these objects.

The remarkable similarity of the X-ray spectra of the young supermassive black holes to those of much older ones means that the supermassive black holes and their accretion disks, were already in place less than a billion years after the Big Bang. One possibility is that millions of 100 solar mass black holes formed from the collapse of massive stars in the young galaxy, and subsequently built up a billion-solar mass black hole in the center of the galaxy through mergers and accretion of gas.

To answer the question of how and when supermassive black holes were formed, astronomers plan to use the very deep Chandra exposures and other surveys to identify and study quasars at even earlier ages.

The paper by Schwartz and Virani on SDSSp J1306 was published in the November 1, 2004 issue of The Astrophysical Journal. The paper by Duncan Farrah and colleagues on SDSS J1030 was published in the August 10, 2004 issue of The Astrophysical Journal.

Chandra observed J1306 with its Advanced CCD Imaging Spectrometer (ACIS) instrument for approximately 33 hours in November 2003. NASA’s Marshall Space Flight Center, Huntsville, Ala., manages the Chandra program for NASA’s Office of Space Science, Washington. Northrop Grumman of Redondo Beach, Calif., formerly TRW, Inc., was the prime development contractor for the observatory. The Smithsonian Astrophysical Observatory controls science and flight operations from the Chandra X-ray Center in Cambridge, Mass.

Additional information and images are available at:
http://chandra.harvard.edu and http://chandra.nasa.gov

Original Source: Chandra News Release

Rhea Shows Off a Big Impact

Saturn’s moon Rhea shows off the moon equivalent of a black eye — a bright, rayed crater near its eastern limb.

Rhea is about half the size of Earth’s moon. At 1,528 kilometers (949 miles) across, it is the second-largest moon orbiting Saturn.

The image was taken in visible light with the Cassini spacecraft narrow angle camera on Oct. 24, 2004, at a distance of about 1.7 million kilometers (1 million miles) from Rhea and at a Sun-Rhea-spacecraft, or phase, angle of 40 degrees. The image scale is approximately 10 kilometers (6 miles) per pixel. Cassini will image this hemisphere of Rhea again in mid-January 2005, just after the Huygens probe landing on Titan – with approximately 1-kilometer (0.6-mile) resolution.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Cassini-Huygens mission for NASA’s Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging team is based at the Space Science Institute, Boulder, Colo.

For more information about the Cassini-Huygens mission, visit http://saturn.jpl.nasa.gov and the Cassini imaging team home page, http://ciclops.org .

Original Source: NASA/JPL/SSI News Release

Atacama Desert From Space

This Envisat image was acquired over northern Chile’s Atacama Desert, the driest place on Earth outside of the Antarctic dry valleys.

Bounded on the west by the Pacific and on the east by the Andes, the Atacama Desert only knows rainfall between two and four times a century. The first sight of green in this Medium Resolution Imaging Spectrometer (MERIS) image occurs some 200 kilometres west of the coast, at the foothills of the Western Cordillera, where wispy white clouds start to make an appearance.

There are some parts of the desert where rainfall has never been recorded. The only moisture available comes from a dense fog known as camanchaca, formed when cold air associated with ocean currents originating in the Antarctic hits warmer air. This fog is literally harvested by plants and animals alike, including Atacama’s human inhabitants who use ‘fog nets’ to capture it for drinking water.

The landscape of the Atacama Desert is no less stark than its meteorology: a plateau covered with lava flows and salt basins. The conspicuous white area below the image centre is the Atacama Salt Flat, just to the south of the small village San Pedro de Atacama, regarded as the centre of the desert.

The Atacama is rich in copper and nitrates ? it has been the subject of border disputes between Chile and Bolivia for this reason – and so is strewn with abandoned mines. Today the European Southern Observatory (ESO) has located in high zones of the Atacama, astronomers treasuring the region’s remoteness and dry air. The Pan-American Highway runs north-south through the desert.

Along the Pacific coast, the characteristic tuft-shape of the Mejillones peninsula is visible, where the town of Antofagasta lies just south of Moreno Bay on the southern side of the formation.

This MERIS full resolution image was acquired on 10 January 2003 and has a spatial resolution of 200 metres.

Original Source: ESA News Release

Tiny Mimas, Huge Saturn

Tiny Mimas is dwarfed by a huge white storm and dark waves on the edge of a cloud band in Saturn’s atmosphere.

Although the east-west winds on Saturn are stronger than on Earth or even Jupiter, the contrast in appearance between these zones is more muted, and the departures of the wind speeds from east to west are lower.

The image was taken with the Cassini spacecraft narrow angle camera on Sept. 25, 2004, at a distance of 7.8 million kilometers (4.8 million miles) from Saturn through a filter sensitive to wavelengths of infrared light centered at 727 nanometers. The image scale is 46 kilometers (29 miles) per pixel.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Cassini-Huygens mission for NASA’s Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging team is based at the Space Science Institute, Boulder, Colo.

For more information about the Cassini-Huygens mission, visit http://saturn.jpl.nasa.gov and the Cassini imaging team home page, http://ciclops.org.

Original Source: NASA/JPL News Release

It’s a Galaxy Eat Galaxy Universe

Subaru telescope has witnessed a large galaxy in the act of devouring a small companion galaxy in a new image obtained by Yoshiaki Taniguchi (Tohoku University), Shunji Sasaki (Tohoku University), Nicolas Scoville (California Institute of Technology) and colleagues. The evidence is a wispy band of stars extending over 500 thousand light years, the faintest and longest known example of its kind.

Current theories of galaxy formation suggest that large galaxies like the Milky Way grow by consuming smaller dwarf galaxies. Evidence of this process can be found in our own galactic neighborhood. Some stars in the Milky Way appear to have once belonged to a small nearby galaxy called the Sagitarius Dwarf. Our closest large neighbor galaxy Andromeda also shows evidence for past galactic astronomy. However, in both cases these conclusions are inferred from “post-digestive” observations.

The destruction of dwarf galaxies is difficult to observe because dwarf galaxies are inherently faint and their light becomes increasingly diffuse as stars get pulled away by a larger galaxy. The only previously known observation of the destruction of a dwarf galaxy in progress is from the Advanced Camera for Surveys on the Hubble Space Telescope.

Taniguchi, Sasaki, Scoville and colleagues serendipitously discovered the large elliptical galaxy (COSMOS J100003+020146) pulling apart the dwarf galaxy (COSMOS J095959+020206) while observing an area of sky in the constellation Sextans to study the properties of galaxies over large scales in space and time. The pair of galaxies is about one billion light years away and the distance between the two galaxies is about 330 thousand light years.

The thin band of stars extending from the dwarf galaxy both toward and away from the large elliptical galaxy reveals that the gravity of the elliptical is tidally tearing the dwarf apart. Stars that are closest to the elliptical galaxy experience a stronger pull than stars in the center of the dwarf galaxy, and stars on the opposite side experience a weaker pull. As a result, the dwarf galaxy becomes stretched and looks as if it’s being pulled from two opposite directions even though there is only one galaxy doing the pulling. This effect is comparable to how two areas on the opposite sides of Earth experience high tide at the same time even though there is only one Moon tugging on Earth’s oceans.

The tidally torn strip of stars in the newly observed pair of galaxies is five times more extended and three times fainter in surface brightness than the one observed with Hubble Space Telescope. Subaru telescope’s ability to gather large amounts of light and focus it into a superbly sharp image was essential for this new discovery.

As astronomers find more examples of galactic cannibalism in action, our knowledge of the history of galaxies should become increasingly vivid. Although no human alive today will be able to witness the ultimate of fate of the newly discovered pair, chances are the elliptical galaxy will be able to complete the meal it’s begun and fully consume its neighbor.

Original Source: Subaru News Release

Life’s There, You Just Need to Dig

Image credit: NASA
A place so barren that NASA uses it as a model for the Martian environment, Chile’s Atacama desert gets rain maybe once a decade. In 2003, scientists reported that the driest Atacama soils were sterile.

Not so, reports a team of Arizona scientists. Bleak though it may be, microbial life lurks beneath the arid surface of the Atacama’s absolute desert.

“We found life, we can culture it, and we can extract and look at its DNA,” said Raina Maier, a professor of soil, water and environmental science at the University of Arizona in Tucson.

The work from her team contradicts last year’s widely reported study that asserted the “Mars-like soils” of the Atacama’s core were the equivalent of the “dry limit of microbial life.”

Maier said, “We are saying, ‘What is the dry limit of life?’ We haven’t reached it yet.”

The Arizona researchers will publish their findings as a letter in the Nov. 19 issue of the journal Science. Maier’s co-authors include UA researchers Kevin Drees, Julie Neilson, David Henderson and Jay Quade and U.S. Geological Survey paleoecologist Julio Betancourt. The project was funded by the National Science Foundation and the National Institute for Environmental and Health Sciences, part of the National Institutes of Health.

The project began not as a search for current life but rather as an attempt to peer into the past and reconstruct the history of the region’s plant communities. Betancourt and Quade, a UA professor of geosciences, have been conducting research in the Atacama for the past seven years.

Some parts of the Atacama have vegetation, but the absolute desert of the Atacama’s core — an area Betancourt describes as “just dirt and rocks” — has none.

Nor does the area have cliffs which harbor ancient piles of vegetation, known as middens, collected and stored by long-gone rodents. Researchers use such fossil plant remains to tell what grew in a place long ago.

So to figure out whether the area had ever been vegetated, Quade and Betancourt had to search the soil for biologically produced minerals such as carbonates. To rule out the possibility that such soil minerals were being produced by present-day microorganisms, the two geoscientists teamed up with UA environmental microbiologist Maier.

In October of 2002, the researchers collected sterile soil samples along a 200-kilometer (120 miles) transect that ran from an elevation of 4,500 meters (almost 15,000 feet) to sea level.

Every 300 meters (about 1,000 feet) along the transect, the team dug a pit and took two soil samples from a depth of 20 to 30 centimeters (8 to 12 inches). To ensure the sample was sterile, every time he took the sample, Betancourt had to clean his hand trowel with Lysol.

“When it’s still, it’s not a problem,” he said. “But when the wind’s blowing at 40 miles per hour, it’s a little more complicated.”

The geoscientists brought their test tubes full of desert soil back to Maier’s lab, where her team wetted the soil samples with sterile water, let them sit for 10 days, and then grew bacteria from them.

“We brought ’em back alive, it turns out,” Betancourt said.

Maier and her team have not yet identified the bacteria that come from the extremely arid environment of the Atacama’s core. She can say they are unusual.

She said, “As a microbiologist, I am interested in how these microbial communities evolve and respond. Can we discover new microbial activities in such extreme environments? Are those activities something we can exploit?”

The team’s findings suggest that how researchers look for life on Mars may affect whether life is found on the Red Planet.

The other researchers who had tested soil from the Atacama had looked for life only down to the depth of four inches. So one rule, Quade quipped, is, “Don’t just scratch the surface.”

Saying that Mars researchers are most likely looking for a needle in a very large haystack, Maier said, “If you aren’t very careful about your Mars protocol, you could miss life that’s there.”

Peter H. Smith, the UA planetary scientist who is the principal investigator for the upcoming Phoenix mission to Mars, said, “Scientists on the Phoenix Mission suspect that there are regions on Mars, arid like the Atacama Desert in Chile, that are conducive to microbial life.” He added, “We will attempt an experiment similar to Maier’s group on Mars during the summer of 2008.”

As for Maier and her colleagues, Betancourt said, “We’re very, very interested in life on Earth and how it functions.”

Maier suspects the microbes may persist in a state of suspended animation during the Atacama Desert’s multi-decadal dry spells.

So the team’s next step is to return to Chile and do experiments on-site. One option is what Maier calls “making our own rainfall event” — adding water to the Atacama’s soils — and seeing whether the team could then detect microbial activity.

Original Source: UA News Release