Posted on by Fraser Cain

Mars is Still Geologically Active

Shifting glaciers and exploding volcanoes aren?t confined to Mars? distant past, according two new reports in the journal Nature.

Glaciers moved from the poles to the tropics 350,000 to 4 million years ago, depositing massive amounts of ice at the base of mountains and volcanoes in the eastern Hellas region near the planet?s equator, based on a report by a team of scientists analyzing images from the Mars Express mission. Scientists also studied images of glacial remnants on the western side of Olympus Mons, the largest of the volcano calderas in the solar system. They found additional evidence of recent ice formation and movement on these tropical mountain glaciers, similar to ones on Mount Kilimanjaro in Africa.

In a second report, the international team reveals previously unknown traces of a major eruption of Hecates Tholus less than 350,000 million years ago. In a depression on the volcano, researchers found glacial deposits estimated to be 5 to 24 million years old.

James Head, professor of geological sciences at Brown University and an author on the Nature papers, said the glacial data suggests recent climate change in Mars? 4.6-billion-year history. The team also concludes that Mars is in an ?interglacial? period. As the planet tilts closer to the sun, ice deposited in lower latitudes will vaporize, changing the face of the Red Planet yet again.

Discovery of the explosive eruption of Hecates Tholus provides more evidence of recent Mars rumblings. In December, members of the same research team revealed that calderas on five major Mars volcanoes were repeatedly active as little as 2 million years ago. The volcanoes, scientists speculated, may even be active today.

?Mars is very dynamic,? said Head, lead author of one of the Nature reports. ?We see that the climate change and geological forces that drive evolution on Earth are happening there.?

Head is part of a 33-institution team analyzing images from Mars Express, launched in June 2003 by the European Space Agency. The High Resolution Stereo Camera, or HRSC, on board the orbiter is producing 3-D images of the planet?s surface.

These sharp, panoramic, full-color pictures provided fodder for a third Nature report. In it, the team offers evidence of a frozen body of water, about the size and depth of the North Sea, in southern Elysium.

A plethora of ice and active volcanoes could provide the water and heat needed to sustain basic life forms on Mars. Fresh data from Mars Express ? and the announcement that live bacteria were found in a 30,000-year-old chunk of Alaskan ice ? is fueling discussion about the possibility of past, even present, life on Mars. In a poll taken at a European Space Agency conference last month, 75 percent of scientists believe bacteria once existed on Mars and 25 percent believe it might still survive there.

Head recently traveled to Antarctica to study glaciers, including bacteria that can withstand the continent?s dry, cold conditions. The average temperature on Mars is estimated to be 67 degrees below freezing. Similar temperatures are clocked in Antarctica?s frigid interior.

?We?re now seeing geological characteristics on Mars that could be related to life,? Head said. ?But we?re a long way from knowing that life does indeed exist. The glacial deposits we studied would be accessible for sampling in future space missions. If we had ice to study, we would know a lot more about climate change on Mars and whether life is a possibility there.?

The European Space Agency, the German Aerospace Center and the Freie Universitaet in Berlin built and flew the HRSC and processed data from the camera. The National Aeronautics and Space Administration (NASA) supported Head?s work.

Original Source: Brown University

Posted on by Fraser Cain

Problem with Opportunity’s Mineral Finding Tool

Image credit: NASA/JPL
NASA has suspended use of one of the mineral-identifying tools on the Opportunity Mars rover while experts troubleshoot a problem with getting data from the instrument, the robot’s miniature thermal emission spectrometer.

“As always, our first priority is to protect the instrument, so we have turned it off while we plan diagnostic tests,” said Jim Erickson of NASA’s Jet Propulsion Laboratory, Pasadena, Calif., project manager for the Mars Exploration Rover Project. “Opportunity’s other instruments are healthy and providing excellent science, and Spirit’s entire instrument suite is working well and being kept busy by the science team.”

Both Opportunity and Spirit, its twin, have been examining Mars since January 2004, more than four times as long as their successful three-month primary missions. While researchers work to diagnose the spectrometer-data problem and seek the best way to mend it or work around it, Opportunity is continuing its journey and observing a crater called “Vostok.” On the other side of the planet, meanwhile, martian winds have revealed themselves as dust devils in new images from Spirit and caused mixed effects on the rover itself, depositing dust on a camera and removing dust from solar panels.

On March 3 and 4, Opportunity transmitted data sets for 17 successful readings by its miniature thermal emission spectrometer but also reported that eight other attempted readings yielded incomplete data sets. This spectrometer, from high on the rover’s mast, observes rocks and other targets from afar. It measures the infrared radiation they emit in 167 different wavelengths, providing information about the targets’ composition. Two other types of spectrometers, mounted on the rover’s robotic arm, provide additional information about composition when the rover is close enough to touch the target.

Researchers are considering several possible root causes for the spectrometer-data problem. One possibility is malfunctioning of an optical switch that tells a mirror in the instrument when to begin moving. Another is that the mirror is not properly moving at a constant velocity. “If it is the optical switch, we could use a redundant one built into the instrument,” said Dr. Phil Christensen of Arizona State University, Tempe, lead scientist for the miniature thermal emission spectrometers on both rovers. He added that, if the root cause cannot be remedied, scientists could still get useful data from the instrument in its currently impaired condition.

Even a total loss of the miniature thermal emission spectrometer would not end the rover’s usefulness. In fact, NASA took a calculated risk by disabling this instrument on Opportunity 10 months ago, though the current problem appears unrelated to potential damage anticipated then. At that time, rover operators began using a “deep sleep” technique to conserve energy on Opportunity during reduced-sunshine months of Mars’ winter. Turning off power to overnight heaters let the instrument get cold enough to possibly damage its beam-splitter. However, the spectrometer kept working through the coldest months. Christensen said, “What we’re seeing now does not appear to be any problem with the beam-splitter.”

The rover team is not restricting use of Spirit’s miniature thermal emission spectrometer while troubleshooting the problem on Opportunity.

Spirit’s work capabilities grew with a sudden jump in output from solar panels on March 9, which caused the daily power supply to double. In a possibly related development three days earlier, some dust appeared to have blown onto lenses of Spirit’s front hazard-avoidance camera, enough for slight mottling in images from both the left and right eyes of the stereo camera, but not enough to affect the usefulness of the camera. Mottling in left-eye images cleared markedly the same day the power increased. Team members speculated that Spirit’s power boost, like similar ones on Opportunity in October, resulted from wind removing some accumulated dust from solar panels. Spirit captured pictures of dust-lofting whirlwinds on March 10, adding evidence for windy local conditions. Images the next day showed solar panels cleaned of most of their dust buildup.

Opportunity’s rear hazard-avoidance camera picked up some dust contamination three months ago. The dust on it has not affected operations and has neither decreased nor increased perceptibly since first noticed. No dust has contaminated lenses of the navigation cameras or panoramic cameras on either rover. From all cameras combined, the rovers have returned more than 72,000 images. Images and other geological data from Spirit and Opportunity are successfully providing unprecedented evidence about wet environmental conditions in Mars’ past.

JPL, a division of the California Institute of Technology in Pasadena, has managed NASA’s Mars Exploration Rover project since it began in 2000. Images and additional information about the rovers and their discoveries are available on the Internet at http://www.nasa.gov/vision/universe/solarsystem/mer_main.html and http://marsrovers.jpl.nasa.gov.

Original Source: NASA/JPL News Release

Posted on by Fraser Cain

Dark Energy in our Galactic Neighbourhood

Astrophysicists in recent years have found evidence for a force they call dark energy in observations from the farthest reaches of the universe, billions of light years away.

Now an international team of researchers has used data from powerful computer models, supported by observations from the Hubble Space Telescope, to find evidence of dark energy right in our own cosmic neighborhood.

The data paint a picture of the universe as a virtual sea of dark energy, with billions of galaxies as islands emerging from the sea, said Fabio Governato, a University of Washington research associate professor of astronomy and a researcher with Italy’s National Institute for Astrophysics.

In 1929 astronomer Edwin Hubble demonstrated that galaxies are moving away from each other, which supported the theory that the universe has been expanding since the big bang. In 1999 cosmologists reported evidence that an unusual force, called dark energy, was actually causing the expansion of the universe to accelerate.

However, the expansion is slower than it would be otherwise because of the tug of gravity among galaxies. As the battle between the attraction of gravity and the repellent force of dark energy plays out, cosmologists are left to ponder whether the expansion will continue forever or if the universe will collapse in a “big crunch.”

In 1997, Governato designed a computer model to simulate evolution of the universe from the big bang until the present. His research group found the model could not duplicate the smooth expansion that had been observed among galaxies around the Milky Way, the galaxy in which Earth resides. In fact, the model produced deviations from a purely radial expansion that were three to seven times higher than astronomers had actually observed, Governato said.

“The observed motion was small, and we could not duplicate it without the presence of dark energy,” he said. “When we added the dark energy, we got a perfect match.”

Governato is one of three authors of a paper describing the work, scheduled for publication in the Monthly Notices of the Royal Astronomical Society, an astronomy journal in the United Kingdom. Co-authors are Andrea Maccio of the University of Zurich in Switzerland and Cathy Horellou of Chalmers University of Technology in Sweden. The work was supported by grants from the National Science Foundation and Vetenskapsr?det, the Swedish Research Council.

The authors, part of an international research collaboration called the N-Body Shop that originated at the UW, ran simulations of universe expansion on powerful supercomputers in Italy and Alaska. Their findings provide supporting evidence for a sea of dark energy surrounding galaxies.

“We studied the properties of galaxies close to the Milky Way instead of looking billions of light years away,” Governato said. “It’s like traveling from Seattle to Portland, Ore., rather than from Seattle to New York, to measure the Earth’s curvature.”

Original Source: University of Washington News Release

Posted on by Fraser Cain

Enceladus has an Atmosphere

Image credit: NASA/JPL/SSI
The Cassini spacecraft’s two close flybys of Saturn’s icy moon Enceladus have revealed that the moon has a significant atmosphere. Scientists, using Cassini’s magnetometer instrument for their studies, say the source may be volcanism, geysers, or gases escaping from the surface or the interior.

When Cassini had its first encounter with Enceladus on Feb. 17 at an altitude of 1,167 kilometers (725 miles), the magnetometer instrument saw a striking signature in the magnetic field. On March 9, Cassini approached to within 500 kilometers (310 miles) of Enceladus’ surface and obtained additional evidence.

The observations showed a bending of the magnetic field, with the magnetospheric plasma being slowed and deflected by the moon. In addition, magnetic field oscillations were observed. These are caused when electrically charged (or ionized) molecules interact with the magnetic field by spiraling around the field line. This interaction creates characteristic oscillations in the magnetic field at frequencies that can be used to identify the molecule. The observations from the Enceladus flybys are believed to be due to ionized water vapor.

“These new results from Cassini may be the first evidence of gases originating either from the surface or possibly from the interior of Enceladus,” said Dr. Michele Dougherty, principal investigator for the Cassini magnetometer and professor at Imperial College in London. In 1981, NASA’s Voyager spacecraft flew by Enceladus at a distance of 90,000 kilometers (56,000 miles) without detecting an atmosphere. It’s possible detection was beyond Voyager’s capabilities, or something may have changed since that flyby.

This is the first time since Cassini arrived in orbit around Saturn last summer that an atmosphere has been detected around a moon of Saturn, other than its largest moon, Titan. Enceladus is a relatively small moon. The amount of gravity it exerts is not enough to hold an atmosphere very long. Therefore, at Enceladus, a strong continuous source is required to maintain the atmosphere.

The need for such a strong source leads scientists to consider eruptions, such as volcanoes and geysers. If such eruptions are present, Enceladus would join two other such active moons, Io at Jupiter and Triton at Neptune. “Enceladus could be Saturn’s more benign counterpart to Jupiter’s dramatic Io,” said Dr. Fritz Neubauer, co-investigator for the Cassini magnetometer, and a professor at the University of Cologne in Germany.

Since the Voyager flyby, scientists have suspected that this moon is geologically active and is the source of Saturn’s icy E ring. Enceladus is the most reflective object in the solar system, reflecting about 90 percent of the sunlight that hits it. If Enceladus does have ice volcanoes, the high reflectivity of the moon’s surface might result from continuous deposition of icy particles originating from the volcanoes.

Enceladus’ diameter is about 500 kilometers (310 miles), which would fit in the state of Arizona. Yet despite its small size, Enceladus exhibits one of the most interesting surfaces of all the icy satellites.

For images and information on the Cassini mission visit http://saturn.jpl.nasa.gov and http://www.nasa.gov/cassini.

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 was designed, developed and assembled at JPL.

Original Source: NASA/JPL News Release

Posted on by Fraser Cain

Robot Finds Life in the Desert

Image credit: CMU
Current Mars expeditions raise the tantalizing possibility that there may be life somewhere on the red planet. But just how will future missions find it? A system being developed by Carnegie Mellon scientists could provide the answer.

At the 36th Lunar and Planetary Science Conference in Houston this week (March 14-18), Carnegie Mellon scientist Alan Waggoner is presenting results of the life detection system’s recent performance in Chile’s Atacama Desert, where it found growing lichens and bacterial colonies. This marks the first time a rover-based automated technology has been used to identify life in this harsh region, which serves as a test bed for technology that could be deployed in future Mars missions.

“Our life detection system worked very well, and something like it ultimately may enable robots to look for life on Mars,” says Waggoner, a member of the “Life in the Atacama” project team and director of the Molecular Biosensor and Imaging Center at Carnegie Mellon’s Mellon College of Science.

The “Life in the Atacama” 2004 field season?from August to mid-October?was the second phase of a three-year program whose goal is to understand how life can be detected by a rover that is being controlled by a remote science team. The project is part of NASA’s Astrobiology Science and Technology Program for Exploring Planets, or ASTEP, which concentrates on pushing the limits of technology in harsh environments.

David Wettergreen, associate research professor in Carnegie Mellon’s Robotics Institute, leads rover development and field investigation. Nathalie Cabrol, a planetary scientist at NASA Ames Research Center and the SETI Institute, leads the science investigation.

Life is barely detectable over most areas of the Atacama, but the rover’s instruments were able to detect lichens and bacterial colonies in two areas: a coastal region with a more humid climate and an interior, very arid region less hospitable to life.

“We saw very clear signals from chlorophyll, DNA and protein. And we were able to visually identify biological materials from a standard image captured by the rover,” says Waggoner.

“Taken together, these four pieces of evidence are strong indicators of life. Now, our findings are being confirmed in the lab. Samples collected in the Atacama were examined, and scientists found that they contained life. The lichens and bacteria in the samples are growing and awaiting analysis.”

Waggoner and his colleagues have designed a life detection system equipped to detect fluorescence signals from sparse life forms, including those that are mere millimeters in size. Their fluorescence imager, which is located underneath the rover, detects signals from chlorophyll-based life, such as cyanobacteria in lichens, and fluorescent signals from a set of dyes designed to light up only when they bind to nucleic acid, protein, lipid or carbohydrate?all molecules of life.

“We don’t know of other remote methods capable both of detecting low levels of micro-organisms and visualizing high levels incorporated as biofilms or colonies,” says Gregory Fisher, project imaging scientist.

“Our fluorescent imager is the first imaging system to work in the daylight while in the shade of the rover. The rover uses solar energy to operate so it needs to travel during daylight hours. Many times, the images we capture may only reveal a faint signal. Any sunlight that leaks in to the camera of a conventional fluorescence imager would obscure the signal,” Waggoner says.

“To avoid this problem, we designed our system to excite dyes with high intensity flashes of light. The camera only opens during those flashes, so we are able to capture a strong fluorescence signal during daytime exploration,” says Shmuel Weinstein, project manager.

During the mission, a remote science team located in Pittsburgh instructed the rover’s operations. A ground team at the site collected samples studied by the rover to bring back for further examination in the lab. On a typical day in the field, the rover followed a path designated the previous day by the remote operations science team. The rover stopped occasionally to perform detailed surface inspection, effectively creating a “macroscopic quilt” of geologic and biological data in selected 10 by 10 centimeter panels. After the rover departed a region, the ground team collected samples examined by the rover.

“Based on the rover findings in the field and our tests in the laboratory, there is not one example of the rover giving a false positive. Every sample we tested had bacteria in it,” says Edwin Minkley, director of the Center for Biotechnology and Environmental Processes in the Department of Biological Sciences.

Minkley is conducting analyses to determine the genetic characteristics of the recovered bacteria to identify the different microbial species present in the samples. He also is testing the bacteria’s sensitivity to ultraviolet (UV) radiation. One hypothesis is that the bacteria may have greater UV resistance because they are exposed to extreme UV radiation in the desert environment. According to Minkley, this characterization also may explain why such a high proportion of the bacteria from the most arid site are pigmented?red, yellow or pink?as they grow in the laboratory.

The first phase of the project began in 2003 when a solar-powered robot named Hyperion, also developed at Carnegie Mellon, was taken to the Atacama as a research test bed. Scientists conducted experiments with Hyperion to determine the optimum design, software and instrumentation for a robot that would be used in more extensive experiments conducted in 2004 and in 2005. Zo?, the rover used in the 2004 field season, is the result of that work. In the final year of the project, plans call for Zo?, equipped with a full array of instruments, to operate autonomously as it travels 50 kilometers over a two-month period.

The science team, led by Cabrol, is made up of geologists and biologists who study both Earth and Mars at institutions including NASA’s Ames Research Center and Johnson Space Center, SETI Institute, Jet Propulsion Laboratory, the University of Tennessee, Carnegie Mellon, Universidad Catolica del Norte (Chile), the University of Arizona, UCLA, the British Antarctic Survey, and the International Research School of Planetary Sciences (Pescara, Italy).

The Life in the Atacama project is funded with a three-year, $3 million grant from NASA to Carnegie Mellon’s Robotics Institute. William “Red” Whittaker is the principal investigator. Waggoner is principal investigator for the companion project in life-detection instruments, which garnered a separate $900,000 grant from NASA.

Original Source: CMU News Release

Posted on by Fraser Cain

Helium-Richest Stars Found

On the basis of stellar spectra totalling more than 200 hours of effective exposure time with the 8.2-m VLT Kueyen telescope at Paranal (Chile), a team of astronomers [1] has made a surprising discovery about the stars in the giant southern globular cluster Omega Centauri.

It has been known for some time that, contrary to other clusters of this type, this stellar cluster harbours two different populations of stars that still burn hydrogen in their centres. One population, accounting for one quarter of its stars, is bluer than the other.

Using the FLAMES multi-object spectrograph that is particularly well suited to this kind of work, the astronomers found that the bluer stars contain more heavy elements than those of the redder population. This was exactly opposite to the expectation and they are led to the conclusion that the bluer stars have an overabundance of the light element helium of more than 50%. They are in fact the most helium rich stars ever found. But why is this so?

The team suggests that this puzzle may be explained in the following way. First, a great burst of star formation took place during which all the stars of the red population were produced. As other normal stars, these stars transformed their hydrogen into helium by nuclear burning. Some of them, with masses of 10-12 times the mass of the Sun, soon thereafter exploded as supernovae, thereby enriching the interstellar medium in the globular cluster with helium. Next, the blue population stars formed from this helium-rich medium.

This unexpected discovery provides important new insights into the way stars may form in larger stellar systems.

Two Populations
Globular clusters are large stellar clusters some of which contain hundreds of thousands of stars. It is generally believed that all stars belonging to the same globular cluster were born together, from the same interstellar cloud and at the same time. Strangely, however, this seems not to be the case for the large southern globular cluster Omega Centauri.

Omega Centauri is the galactic globular cluster with the most complex stellar population. Its large mass may represent an intermediate type of object, between globular clusters and larger stellar systems such as galaxies. In this sense, Omega Centauri is a very useful “laboratory” for better understanding the history of star formation.

However, it appears that the more information astronomers acquire about the stars in this cluster, the less they seem to understand the origin of these stars. But now, new intriguing results from the ESO Very Large Telescope (VLT) may show a possible way of resolving the present, apparently contradictory results.

Last year, an international team of astronomers [1], using data from the Hubble Space Telescope (HST), showed that Omega Centauri, unlike all other globular clusters, possesses two distinct populations of stars burning hydrogen in their centre. Even more puzzling was the discovery that the bluer population was more rare than the redder one: they accounted for only a quarter of the total number of stars still burning hydrogen in their central core. This is exactly the opposite of what the astronomers had expected, based on the observations of more evolved stars in this cluster.

Over Two Weeks of Total Exposure Time!
The same team of astronomers then went on to observe some of the stars from the two populations in this cluster by means of the FLAMES instrument on the Very Large Telescope at Paranal. They used the MEDUSA mode, allowing to obtain no less than 130 spectra simultaneously.

Twelve one-hour spectra were obtained for 17 stars of the blue population and the same number stars from the red one. These stars have magnitudes between 20 and 21, i.e., they are between 500,000 and 1 million times fainter than what can be seen with the unaided eye.

The individual spectra of stars from each population were then co-added. This produced a “mean” spectrum of a blue-population star and another of a red-population. Each of these spectra represents a total of no less than 204 hours of exposure time and accordingly provides information in unrivalled detail about these stars, especially in terms of their chemical composition.

The scientific outcome matches the technical achievement!
From a careful study of the combined spectra, the astronomers were able to establish that – contrary to all prior expectations – the bluer stars are more “metal-rich” (by a factor two) than the redder ones. “The latter were found to have an abundance of elements more massive than helium corresponding to about 1/40 the solar abundance [2] “, explains Raffaele Gratton of INAF-Osservatorio Astronomico di Padova in Italy. “This is indeed very puzzling as current models of stars predict that the more metal-rich a star is, the redder it ought to be”.

Giampaolo Piotto (University of Padova, Italy), leader of the team, thinks that there is a solution to this celestial puzzle: “The only way we can explain this discrepancy is by assuming that the two populations of stars have a different abundance of helium. We find that while the red stars have a normal helium abundance, the bluer stars must be enriched in helium by more than 50% with respect to the other population!”

These stars are thus the most helium-rich stars ever found, and not by just a few percent! It took some 8 billion years for the Milky Way Galaxy to increase its helium abundance from the primordial 24% value (created by the Big Bang) to the present solar 28% value, and yet in a globular cluster that formed only 1 or 2 billion years after the Big Bang, stars were produced with 39% of helium!

Contamination from supernovae
The obvious question is now: “Where does all this helium come from?”

Luigi Bedin (ESO), another member of the team, suggests that the solution might be connected to supernovae: “The scenario we presently favour is one in which the high helium content originates from material ejected during the supernovae explosions of massive stars. It is possible that the total mass of Omega Centauri was just right to allow the material expelled by high-mass supernovae to escape, while the matter from explosions of stars with about 10-12 times the mass of the Sun was retained.”

According to this scenario, Omega Centauri must therefore have seen two generations of stars. The first generation, with primordial helium abundance, produced the redder stars. A few tens of million years later, the most massive stars of this first generation exploded as supernovae. The helium-enriched matter that was expelled during the explosions of stars with 10-12 times the mass of the Sun “polluted” the globular cluster. Then a second population of stars, the bluer ones, formed from this helium-rich gas.

The scientists acknowledge that certain problems still remain and that the last word may not yet have been said about this unusual globular cluster. But the new results constitute an important step towards the solution of the biggest mystery of all: why is Omega Centauri the only one among the galactic globular cluster that was able to produce super helium-rich stars?

More information
The research presented here appeared in the March 10 issue of the Astrophysical Journal, Vol. 621, p. 777 (“Metallicities on the Double Main Sequence of Omega Centauri Imply Large Helium Enhancement” by G. Piotto et al.) and is available for download as astro-ph/0412016.

Notes
[1]: The team is composed of Giampaolo Piotto, Giovanni Carraro, Sandro Villanova, and Yazan Momany (University of Padova, Italy), Luigi R. Bedin (ESO, Garching), Raffaele Gratton and Sara Lucatello (INAF- Osservatorio Astronomico di Padova, Italy), Santi Cassisi (INAF- Osservatorio Astronomico di Teramo, Italy), Alejandra Recio-Blanco (Observatoire de Nice, France), Ivan R. King (University of Washington, USA), and Jay Anderson (Rice University, USA).

[2]: Helium is the second most abundant chemical element in the Universe, after hydrogen. The Sun contains about 70% hydrogen and 28% helium. The rest, about 2%, is made of all elements more heavier than helium. They are commonly referred to by astronomers as “metals”.

Original Source: ESO News Release

Posted on by Fraser Cain

What’s Up This Week – Mar 14 – 20, 2005

Image credit: NOAO/AURA/ASF
Monday, March 14 – Today is the birthday of Albert Einstein. Often called the most brilliant mind of our times, I’d rather think of him as a man who never wore socks, believed that curiosity and imagination were more important than knowledge and made a math mistake when helping a student with homework. Now that’s a man you can admire!

For our friends in eastern Europe, we wish you clear skies as the Moon occults bright star, Delta Aries during the early evening hours. Please check IOTA information for precise times and locations. For the rest of us, tonight’s Moon will offer an outstanding view of Mare Crisium, easily identified with binoculars in the northeast section. Let’s turn the telescope its way to discover two small interior craters that will be near the terminator. Not far from the western wall, look for small craters Pierce in the northwest and Picard to the southwest.

Give the Moon time to wester and let’s head back out for both binocular and telescopic open cluster – M50. By drawing a mental line between Sirius and Procyon, you will find this sparkling collection of stars easy to find. Cataloged by Messier in April of 1772, this loose – and somewhat heart-shaped gathering of blue/white stars resides around 3000 light years distant and contains several red giants like the prominent one on its southern edge.

Tuesday, March 15 – Although Mercury has passed its greatest elongation, it is still possible for northern hemisphere observes to catch the elusive inner planet planet about a fist’s width above the western horizon just after sunset. Look southwest of bright Gamma Pegasus to help guide you.

For the southern hemisphere, keep watch for the Gamma-Normid meteor shower with an average fall rate of about five to eight per hour.

Tonight Mare Fecunditatis will be visible in the southeast section of the Moon to binoculars with the bright ring of Langrenus on its eastern shore. For telescopic viewers wishing a challenge, focus on the area where Mare Fecunditatis and the northern Tranquillitatis meet. The shallow bright ring is Crater Taruntius. About midway across Fecunditatis expanse to the south you will see two small pockmarks sitting side by side. Both are named for Charles Messier, crater Messier A is to the west. As you scan the sky around the Moon, be sure to check out how close the Plieades are. At 8:00 pm EST, the M45 will be only one degree away to the north.

Wednesday, March 16 – Tonight will be the peak of the Corona-Australid meteor shower. Favouring more southern observers, be on the lookout for around five to seven bright streaks per hour moving from south to north.

Today in 1926, Robert Goddard launched the first liquid fuel rocket that reached the amazing height of about twelve meters. How about if we set our sites about 20 million times higher? For binoculars, the Moon will reveal the beginnings of Mare Frigorius to the north joined by Mare Serenitatis to its south. Look for the dark floored Lacus Somniorum between them. Steady hands will reveal the ancient Crater Posidonius, but try a telescope. South of Posidonius along the eastern shore is the ruins of Le Monnier – the Luna 21 landing site. Continue south approximately the same distance and you will see a shallow crater known as Littrow. Look to the mountains just south of the edge to discover the Apollo 17 landing area.

If you’ve got a clear night, why not wait a few hours and return for the M44? If skies are still bright, form a triangle between Pollux, Regulus and Procyon and set your binoculars in the center. Known as the “Beehive”, our stellar swarm is only about 500 light years away. With a wide range of magnitudes to feast the eyes upon, look for at least a handful of orange stars in the blues and whites. Judging by these well evolved members, science concludes this cluster is about 400 million years old.

Thursday, March 17 – Happy St. Patrick’s Day! All of Europe will be favoured tonight as the Moon occults 4.6 magnitude 136 Tauri in the early evening hours. Please check IOTA for specific times in your area. For west/central and southeast Australia and New Zealand, you will fare better with brighter Beta Tauri on this universal date. Check this IOTA page to compute times for your location.

The early evening Moon will also offer up the Apollo 11 landing area, but since we’ve become familiar with Sabine and Ritter, let’s head north of the pair for a more unusual feature. Tonight use your telescope to locate the Rima Ariadaeus located on the terminator about midway along the west shore ofMare Tranquillatatis. It will appear as a fine “crack” running roughly from east to west through the bright landscape.

Friday, March 18 – The Moon will dominate the early evening hours, but why not enjoy its features as we scan the terminator in binoculars to enjoy the Caucasus Mountains and outstanding craters Aristillus and Autolycus to the north. Just south of this outstanding pair is a rather curious dark area known as Palus Putredinus, or the “Rotten Swamp”. On September 13, 1959 European observers witnessed the impact of Lunik 2 in this area.

The first “space walk” was performed by Cosmonaut Alexei Leonov on this day in 1965, but tonight let’s walk across space as we head towards the back of the lion’s head – Gamma Leonis. Known as Algieba, this magnitude 2.6 yellow star will appear to have a companion star to its south in binoculars, but a telescope is needed to see the 3.8 magnitude B star to the east/southeast. At around 100 light years away, this yellow/orange pair share an elliptical orbit about 300 AU apart. It takes about 600 years for this pair to revolve and they will reach maximum separation in just another 95 years.

Saturday, March 19 – Tonight will be central Europe’s turn for yet another occultation as the Moon covers Upsilon Geminorum. Check IOTA for times and locations. For northwestern Australia, you have Iota Geminorum on your list, but be advised this is a universal date.

As we view the Moon through binoculars tonight, we see near the terminator to the south three very prominent craters in a line. From north to south their names are Ptolemy, Alphonsus and Arzachel. Telescopically, the centermost – Alphonsus – has a wonderful history of volcanism. Its small central mountain is the only place on the Moon where photographic evidence of outgassing was verified by a spectrogram. For eastern time zones, be sure to have another look around 11:00 pm when the creamy yellow Saturn will be about five degrees south of Selene.

Sunday, March 20 – Tonight the Moon will be at apogee – the furthest from the Earth – at around 251,560 miles. Even at this incredible distance, no feature on the Moon will be more prominent to binoculars and telescopes than the dazzling class one Crater Copernicus. Thanks to the work of Shoemaker, there is no doubt this impressive impact crater bears similarities to own our terrestrial formations. The more power and aperture you add to this crater, the more details you will see.

Just because skies are bright tonight doesn’t mean that astronomy has come to an end! Take the time to visit with Saturn and note the position of Titan as well as its smaller moons. If skies cooperate, stay up a bit later and view Jupiter. With its many satellite events and transits of the “Great Red” spot, you are sure to catch something new and different each time you look.

Until next week, keep looking up and traveling at Light Speed… ~Tammy Plotner

Posted on by Fraser Cain

Rover Sees a Dust Devil on Mars

Mars is often enveloped by planet-wide dust storms – their biting winds choke the air and scour the arid surface. Tornado-like dust devils dance across the planet so frequently that their numerous tracks crisscross each other, tracing convoluted designs in the red soil. Martian dust includes magnetic, composite particles, with a mean size of one micron–the equivalent to powdered cement or flour in consistency. This size range is about five percent the width of a human hair.

By comparison to how a dust devil in Arizona might stir up uncultivated farmland, the scale on Mars is much more daunting. “These martian dust devils dwarf the five-to-10 meter terrestrial ones, can be greater than 500 meters in diameter and several thousand meters high. The track patterns are known to change from season to season, so these huge dust pipes must be a large factor in transporting dust and could be responsible for eroding landforms,” said Peter Smith of the University of Arizona (Tucson)

Mars has only a faint atmosphere [less than one percent of terrestrial pressures], yet offers up its history of dust devils as swirling tracks in a remarkable landscape of wind-swept and carved terrain. These tiny twisters tend to appear in the middle afternoon on Mars, when solar heating is maximum and when warm air rises and collides with other pressure fronts to cause circulation.

In his first press conference after the Spirit rover landed, the principal investigator for the rover’s science package, Cornell’s Steven Squyres, described one instance his team has been discussing: the intriguing possibility that at Gusev, over their mission, the rover’s camera may actually be able to animate a dust devil in action.

Squyres informally proposed a mini-series of frames, or twister movie which with some meterological luck, might offer a rare example of surface weather on another planet.

“At the Pathfinder site during its 83 sol mission, approximately thirty dust devils were either sensed by the pressure drop as they passed over the lander, or were imaged by the Pathfinder camera,” says Smith. “Based on these observations, one might expect to see several dust devils per hour from an active site on Mars between 10 am and 3 pm. Few, if any dust devils will be present at other times. Dust devils typically form during late spring and summer and can be found at all latitudes. Exactly, how their population density varies around the planet is currently unknown.”

In addition to Pathfinder’s run-in with a dust devil, previous missions to Mars have run into very dusty days. For instance, there was a dust storm covering the Viking Lander I (VL-1) site on Martian day (1742) or sol 1742 (1 Martian year=669 Earth days). In 1971, Mariner 9 and 2 USSR missions all arrived during a dust storm.

“Rovers and other robots must be carefully designed to withstand the sandblasting that they will endure from dust devils,” said Smith. “Bearing surfaces and solar panels must be protected and dust accumulation on solar panels will lower their efficiency.”

Actual mini-tornadoes of this magnetic dust, or dust devils, have been caught in the act by orbital cameras are highlighted by images below. These miniature tornadoes can span about 10 to 100 meters wide with 20- to 60-mile-per-hour (32- to 96-km/hr) winds swirling around a heated column of rising air. One might expect to see several dust devils per hour from an active site on Mars between 10 am and 3 pm, when rising afternoon air is hottest.

Original Source: Astrobiology Magazine

Posted on by Fraser Cain

Dr. Mike Griffin Chosen to Lead NASA

The US White House has announced the Dr. Mike Griffin will pick up the reins at NASA, filling the vacancy left by Sean O’Keefe. Griffin is currently the director of space at Johns Hopkins University’s Applied Physics Laboratory (APL), and is a supporter of the new Vision for Space Exploration. Once confirmed by the senate, Griffin will become the 11th Administrator for NASA.

Posted on by Fraser Cain

Atlas V Lofts Satellite for Inmarsat

An Atlas V launch vehicle carried its largest payload to date into orbit tonight, the Inmarsat 4-F1 satellite that weighs nearly 6 metric tons (5,959 kgs/13,138 pounds). This also marked the third launch of the year for International Launch Services (ILS).

The Lockheed Martin-built (NYSE: LMT) Atlas V vehicle, designated AV-004, lifted off at 4:42 p.m. EST (21:42 GMT). It placed the Inmarsat spacecraft in a supersynchronous transfer orbit 32 minutes later. Satellite controllers have confirmed that the spacecraft is functioning properly.

Tonight’s vehicle used the Atlas V “431” configuration, meaning it had a 4-meter-diameter fairing, three solid rocket boosters (SRBs) and a single-engine Centaur upper stage. Atlas V vehicles have now flown five times, three of them with SRBs.

“The Atlas series now has achieved an unprecedented string of 76 successful launches, and we’re proud to count this mission and two others for Inmarsat among them,” said ILS President Mark Albrecht.

“This is a milestone launch for us, also, in terms of the size of the payload,” Albrecht said. “Inmarsat 4-F1 is one of largest commercial communications satellites in the world, as well as the most massive satellite launched by Atlas. Yet it falls into the middle of the Atlas V capability range, demonstrating the flexibility of our design.”

The spacecraft is a Eurostar E3000 model built by EADS Astrium. It is the first in a generation of satellites that will support Inmarsat’s new Broadband Global Area Network (BGAN), delivering internet and intranet content and solutions, video-on-demand, videoconferencing, fax, e-mail, phone and LAN access at speeds up to 432kbit/s almost anywhere in the world. BGAN will also be compatible with third-generation cellular systems. The operating location for Inmarsat 4-F1 is 65 degrees East longitude.

“We thank ILS for the safe delivery of our first I-4 satellite into space,” said Andrew Sukawaty, chairman and CEO of Inmarsat. “The first two I-4 satellites will bring broadband communications to 86 percent of the world. History has been made and the world has become closer through advanced data communications.”

Antoine Bouvier, CEO of EADS Astrium, said: “This successful launch is a major event for EADS Astrium, as Inmarsat-4 is certainly one of the most sophisticated communications satellites ever built. We thank for this achievement International Launch Services, and Inmarsat for the confidence they had in EADS Astrium on this innovative and ambitious program.”

ILS is a joint venture of Lockheed Martin of Bethesda, Md., and Khrunichev State Research and Production Space Center of Moscow. ILS is the global leader in launch services, offering the industry’s two best launch systems: Atlas and Proton. With a remarkable launch rate of 73 missions since 2000, the Atlas and Proton launch vehicles have consistently demonstrated the reliability and flexibility that have made them preferred choice among satellite operators worldwide. Since the beginning of 2003, ILS has signed more new commercial contracts than all of its competitors combined.

Original Source: ILS News Release