(Artist's concept of ExoMars rover planned for launch in 2013. (Credit: European Space Agency

A new life-detecting instrument is preparing for a mission to the Red Planet. The Urey: Mars Organic and Oxidant Detector instrument, developed by a scientist at Scripps Institution of Oceanography at UC San Diego, received approximately $2 million in NASA funding to further refine the design and technology for the European Space Agency's (ESA) 2013 ExoMars Rover Mission.

Named after the late Nobel Laureate and UC San Diego scholar Harold C. Urey, the Urey instrument will perform the first search for key classes of organic molecules in the Martian environment using state-of-the-art analytical methods at part-per-million sensitivities. This highly sensitive instrument is the first with the capability to effectively discriminate between Martian materials produced by biological and non-biological processes. In addition, the investigation will provide definitive oxidation characteristics of those same samples.

Jeffrey Bada of Scripps Oceanography, along with a multinational research team including colleagues Frank Grunthaner of the NASA Jet Propulsion Laboratory, Richard Mathies of UC Berkeley, Aaron Zent of the NASA Ames Research Center, Richard Quinn of the SETI Institute, Pascale Ehrenfreund of the NASA Goddard Spaceflight Center and Mark Sephton of Imperial College, London have designed an investigation using the Urey instrument to look for signs of past or present life on Mars. It will analyze Martian rock and soil samples provided by the ESA-developed ExoMars Rover, for organic molecules and amino acids, the building blocks of life. Urey will be built and tested at the NASA Jet Propulsion Laboratory (JPL) in Pasadena, Calif.

“This next phase of funding assures that the Urey instrument’s design will be completed on schedule and we will be prepared to start building the actual instrument next year,” said Bada, professor of marine chemistry at Scripps and principal investigator of the Urey investigation.

The instrument has been supported by NASA Research and Development funding for the past several years leading up to this transition to Phase A Flight planning and design.

The Urey instrument has been identified as an integral component of ExoMars, a six-month mission on the Red Planet and ESA’s first rover mission to Mars. “We will be working very closely with our European partners over the next year to finalize interfaces and to further solidify how Urey fits into the overall ExoMars payload system,” said Allen Farrington, project manager of the Urey development team at JPL.

A compact instrument that can be held in the palm of one’s hand, Urey will search for trace levels of amine-containing organic molecules by “making espresso” from spoon-sized amounts of Martian soil, freeze drying the liquid to remove the water, and then slowly re-heating the residue, and concentrating the organic molecules by condensing them on a cold trap. A lab-on-a-chip, micro-fluidic, laser-induced fluorescence detector initially developed by team members at UC Berkeley will probe the trap’s contents.

In addition to the organic compound analyses, Urey will also test the Martian samples and environment for their ability to degrade organic compounds through oxidation. The Mars Oxidant Instrument developed by team members at NASA Ames Research Center, JPL and the SETI Institute will enable the scientists to evaluate the stability of compounds directly under Martian conditions. Even if no organic compounds are detected, this oxidation information will provide important data for understanding the reasons why organic compounds might not be preserved on Mars.

             Adapted from materials provided by University of California, San Diego.

Cracks In The Foundation: Fundamental Geological Assumption Relating To Planet Earth Not Quite True

Chondritic meteorites have a similar chemical composition to the sun and are therefore reliable witnesses as to what the solar nebula, from which the planets formed, was composed of. This can be used to deduce what the Earth consists of chemically. However, ETH Zurich researchers have now discovered that strictly speaking this fundamental geological assumption is not true.

Many moons ago, geochemists discovered that the Earth must be identical to the so-called chondritic meteorites in terms of its chemical composition. The latter consist of exactly the same mixture of elements as the sun, which suggests that they mirror the composition of the solar nebula, from which the planets once emerged. This reasoning enables geologists to draw many significant conclusions. For example, geochemists can work out which elements make up the Earth’s core as a result.

Or so they thought: although it may not exactly shatter this geochemical fundamental, a new publication does expose various cracks in the theory. Based on the results of their experiments, a team of researchers, which includes Bernard Bourdon, Professor of Isotope Geochemistry at ETH Zurich, recently concluded in the journal Nature that the Earth may have a slightly different composition to chondritic meteorites after all.

Theory not all that plausible

The basis for the study was the discovery by another team that the element neodymium in the rock found in the Earth’s surface has a somewhat different isotopic make-up compared to the meteorites. As neodymium is a lithophilic element and therefore not present in the Earth’s core, the team suggests, there must be a hidden reservoir in the Earth’s mantle that exhibits a different composition to the rest of it. However, on account of the strong convection in the Earth’s mantle, which gives rise to a continual mixture of the rock, Bourdon’s team did not find this theory all that plausible, and so they started looking for another explanation.

The scientists scrutinized the samarium and neodymium isotopes in rocks from the Earth, meteorites from Mars and the asteroid Vesta more closely and supplemented the values with data from the literature on moonstones. The two elements samarium and neodymium are closely related: the isotopes samarium 147 and samarium 146 namely decompose in the daughter isotopes neodymium 143 and neodymium 142. If you measure the isotopic composition of the two elements, you can reconstruct the processes that occurred in the early stages of the solar system on account of the degradation’s different half-lives.

The new data reveals that rocks on the moon and Mars also exhibit an isotopic composition that differs significantly from that of the chondritic meteorites. However, the values match those of the terrestrial rocks: according to this, the Earth, Moon and Mars have a samarium-neodymium ratio that is five to eight percent above that of the chondritic meteorites. “The variance may not seem all that much”, explains Bourdon. “But it is significant enough to be inconsistent with the classic model”.

How homogenous was the solar nebula?

According to Bourdon, the fact that the three celestial bodies the Earth, the Moon and Mars could have the same isotopic composition proves that the theory of a hidden reservoir in Earth’s mantle is far from holeproof. “Our analyses indicate that a process must have occurred in the first 30 million years of our solar system which resulted in the uneven distribution of matter in the solar system.”

As far as the scientists are concerned, there are two possibilities: the first is that the matter in the solar nebula ceased to be homogenous even before the planets formed, a theory which astrophysicists consider perfectly plausible. This explanation is supported by that fact that the meteorites from the asteroid Vesta, which is considerably further from the sun than Mars, has a different isotopic composition compared to rocks from the Earth, the Moon or Mars. The data indicates that Vesta could have a similar composition to the chondritic meteorites, which also come from the asteroid belt.

The second explanation assumes that a crust formed on the first planetary bodies, the so-called planetesimals. In the course of this, the crusts and mantles of these bodies each exhibited a different composition. According to this theory, when the planets collided with one another their crust was blown away. This left bodies that had another isotopic composition to the original solar nebula, from which today’s planets later emerged.

Journal reference: G. Caro et.al.: Super-chondritic Sm/Nd ratios in Mars, the Earth and the Moon. Nature 452, p.336-339 (2008).

                                Adapted from materials provided by ETH Zurich.

As a powerful electrical storm rages on Saturn with lightning bolts 10,000 times more powerful than those found on Earth, the Cassini spacecraft continues its five-month watch over the dramatic events.

Scientists with NASA's Cassini-Huygens mission have been tracking the visibly bright, lightning-generating storm--the longest continually observed electrical storm ever monitored by Cassini.

Saturn's electrical storms resemble terrestrial thunderstorms, but on a much larger scale. Storms on Saturn have diameters of several thousand kilometers (thousands of miles), and radio signals produced by their lightning are thousands of times more powerful than those produced by terrestrial thunderstorms.

Lightning flashes within the persistent storm produce radio waves called Saturn electrostatic discharges, which the radio and plasma wave science instrument first detected on Nov. 27, 2007. Cassini's imaging cameras monitored the position and appearance of the storm, first spotting it about a week later, on Dec. 6.

"The electrostatic radio outbursts have waxed and waned in intensity for five months now," said Georg Fischer, an associate with the radio and plasma wave science team at the University of Iowa, Iowa City. "We saw similar storms in 2004 and 2006 that each lasted for nearly a month, but this storm is longer-lived by far. And it appeared after nearly two years during which we did not detect any electrical storm activity from Saturn."

The new storm is located in Saturn's southern hemisphere--in a region nicknamed "Storm Alley" by mission scientists--where the previous lightning storms were observed by Cassini. "In order to see the storm, the imaging cameras have to be looking at the right place at the right time, and whenever our cameras see the storm, the radio outbursts are there," said Ulyana Dyudina, an associate of the Cassini imaging team at the California Institute of Technology in Pasadena, Calif.

Cassini's radio plasma wave instrument detects the storm every time it rotates into view, which happens every 10 hours and 40 minutes, the approximate length of a Saturn day. Every few seconds the storm gives off a radio pulse lasting for about a tenth of a second, which is typical of lightning bolts and other electrical discharges. These radio waves are detected even when the storm is over the horizon as viewed from Cassini, a result of the bending of radio waves by the planet's atmosphere.

Amateur astronomers have kept track of the storm over its five-month lifetime. "Since Cassini's camera cannot track the storm every day, the amateur data are invaluable," said Fischer. "I am in continuous contact with astronomers from around the world."

The long-lived storm will likely provide information on the processes powering Saturn's intense lightning activity. Cassini scientists will continue to monitor Storm Alley as the seasons change, bringing the onset of autumn to the planet’s southern hemisphere.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. JPL, a division of Caltech, manages the Cassini 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. The radio and plasma wave science team is based at the University of Iowa, Iowa City.

Color images of the storm are available at: http://saturn.jpl.nasa.gov and http://www.nasa.gov/cassini and http://ciclops.org.

Adapted from materials provided by NASA/Jet Propulsion Laboratory.

An international team of astronomers has discovered two planets that resemble smaller versions of Jupiter and Saturn in a solar system nearly 5,000 light years away. The find suggests that our galaxy hosts many planetary systems like our own, said Scott Gaudi, assistant professor of astronomy at Ohio State

The two planets were revealed when the star they orbit crossed in front of a more distant star as seen from Earth. For a two-week period from late March through early April of 2006, the nearer star magnified the light shining from the farther star. 

The phenomenon is called gravitational microlensing, and this was a particularly dramatic example: the light from the more distant star was magnified 500 times.

The Optical Gravitational Lensing Experiment (OGLE) first detected the event, dubbed OGLE-2006-BLG-109, on March 28, 2006. The Microlensing Follow Up Network (MicroFUN), led by Andrew Gould, professor of astronomy at Ohio State, then joined with OGLE to organize astronomers worldwide to gather observations of it. Andrzej Udalski, professor of astronomy at Warsaw University Observatory, is the leader of OGLE.

Gaudi took the lead in analyzing the data as they came in. As he studied the light signal, he saw a distortion that he thought was caused by a Saturn-mass planet. Then, less than a day later, came an additional distortion he wasn't expecting: a "blip" in the signal that appeared to be caused by a second, larger planet orbiting the same star.

Over the next few months, Gaudi demonstrated that this two-planet interpretation was correct. Then David Bennett, a research associate professor of astrophysics and cosmology at the University of Notre Dame, refined Gaudi's preliminary model using sophisticated software, and revealed additional details about the system.

This is the third time a Jupiter-mass planet was found by microlensing, Gaudi explained. In the previous two cases, additional planets would have been very difficult to detect, had they been there.

"This is the first time we had a high-enough magnification event where we had significant sensitivity to a second planet -- and we found one." Gaudi said. "You could call it luck, but I think it might just mean that these systems are common throughout our galaxy."

The discovery of the double planet system was a triumph for astronomers who use this method, which is of such high sensitivity that it can detect planets similar to those in our own solar system, with the exception of Mercury.

Astronomers have found two planets at once before, "but using other techniques that don't pick up on solar systems like ours," he said.

The newly-discovered planets appear to be gaseous planets like Jupiter and Saturn -- only about 80 percent as big -- and they orbit a star about half the size of the sun. The star is dim and cold compared to ours, issuing only five percent as much light.

Still, the new solar system appears to be a smaller analog of our own. The larger planet is about as massive compared to its star as Jupiter is to ours. The smaller planet shares a similar mass ratio with Saturn.

Also, the smaller planet is roughly twice as far from its star as the larger one, just as Saturn is roughly twice as far away from the sun as Jupiter. Although the star is much dimmer than our sun, temperatures at both planets are likely to be similar to that of Jupiter and Saturn, because they are closer to their star.

"The temperatures are important because these dictate the amount of material that is available for planet formation," Gaudi said. "Most theorists think that the biggest planet in our solar system formed at Jupiter's location because that is the closest to the sun that ice can form. Saturn is the next biggest because it is in the next location further away, where there is less primordial material available to form planets."

"Theorists have wondered whether gas giants in other solar systems would form in the same way as ours did. This system seems to answer in the affirmative."

The fact that astronomers found the planets during the first event that allowed such a detection suggests that these scaled-down versions of our solar system are very common, he added.

Previously, astronomers had found four planets using microlensing; two of those were found by the Ohio State University-based MicroFUN group. The latest two planets make six, and he expects that number to double over the next year as other teams publish new findings.

"We're just getting better at what we do," Gaudi said. "We've hit our stride with this technique."

He has also calculated that the next generation of microlensing experiments -- using telescopes on the ground and in space -- will likely be able to detect analogs to all of our solar system's planets, except for the tiniest one, Mercury.

The current discovery relied on 11 different ground-based telescopes in countries around the world, including New Zealand, Tasmania, Israel, Chile, the Canary Islands, and the United States.

Both professional and amateur skywatchers joined in. People from three other microlensing collaborations -- the Microlensing Observations in Astrophysics (MOA) Collaboration, the Probing Lensing Anomalies NETwork (PLANET), and the RoboNet Collaboration -- all contributed observations and are co-authors of the study with MicroFUN and OGLE.

Gaudi described this microlensing event as the most complicated one ever studied. The astronomers carefully modeled their data on computers, and explored all possible explanations for the light signal. A year and a half later, they were confident that they'd found two planets. In part, their confidence came from additional observations from the W.M. Keck Observatory in Hawaii, which they used to calculate the mass of the star.

This research is reported in the February 15 issue of the journal Science. Ohio State coauthors on the Science paper included Darren DePoy and Richard Pogge, both professors of astronomy; and Subo Dong and Stephan Frank, both graduate students.

Other coauthors hailed from the University of Notre Dame, Warsaw University Observatory, Auckland Observatory, Tel-Aviv University, Farm Cove Observatory, Mt. John Observatory, Lawrence Livermore National Laboratory, Princeton University Observatory, Universidad de Concepción, University of Cambridge, Chungbuk National University, Korea Astronomy and Space Science Institute, Campo Catino Astronomical Observatory, Nagoya University, Massey University, University of Auckland, University of Canterbury, Victoria University, Konan University, Nagano National College of Technology, University of Manchester, Tokyo Metropolitan College of Aeronautics, University of Exeter, Université Pierre et Marie Curie, Liverpool John Moores University, University of St. Andrews, University of Tasmania, Université Paul Sabatier-Toulouse, Dartmouth College, and the University of Oxford.

This work was sponsored by the National Science Foundation; NASA; the Polish Ministry of Scientific Research and Information Technology; the SRC Korea Science & Engineering Foundation; the Korea Astronomy & Space Science Institute; Deutsche Forschungsgemeinschaft; the Particle Physics and Astronomy Research Council; The European Union's Framework Programme for Research and Technological Development; The Israel Science Foundation; the Marsden Fund of New Zealand; the Japan Ministry of Education, Culture, Sports, Science and Technology; and the Japan Society for the Promotion of Science.

                   Adapted from materials provided by Ohio State University.

Scientists hope that a new supercomputer being built by Syracuse University's Department of Physics may help them identify the sound of a celestial black hole. The supercomputer, dubbed SUGAR (SU Gravitational and Relativity Cluster), will soon receive massive amounts of data from the California Institute of Technology (Caltech) that was collected over a two-year period at the Laser Interferometer Gravitational-Wave Observatory (LIGO). 

Duncan Brown, assistant professor of physics and member of SU's Gravitational Wave Group, is assembling SUGAR. The department's Gravitational Wave Group is also part of the LIGO Scientific Collaboration (LSC), a worldwide initiative to detect gravitational waves. Brown worked on the LIGO project at Caltech before coming to SU last August.

Gravitational waves are produced by violent events in the distant universe, such as the collision of black holes or explosions of supernovas. The waves radiate across the universe at the speed of light. While Albert Einstein predicted the existence of these waves in 1916 in his general theory of relativity, it has taken decades to develop the technology to detect them. Construction of the LIGO detectors in Hanford, Wash., and Livingston, La., was completed in 2005. Scientists recently concluded a two-year "science run" of the detectors and are now searching the data for these waves. LSC scientists will be analyzing this data while the sensitivity of the detectors is being improved. Detectors have also been built in France, Germany, Italy and Japan.

Before they can isolate the sound of a black hole from the LIGO data, the scientists must figure out what a black hole sounds like. That's where Einstein's theories come in. Working with colleagues from the Simulating eXtreme Spacetimes (SXS) project, Brown will use SUGAR and Einstein's equations to create models of gravitational wave patterns from the collision of two black holes. SXS is a collaborative project with Caltech and Cornell University.

Black holes are massive gravitational fields in the universe that result from the collapse of giant stars. Because black holes absorb light, they cannot be studied using telescopes or other instruments that rely on light waves. However, scientists believe they can learn more about black holes by listening for their gravitational waves.

"Looking for gravitational waves is like listening to the universe," Brown says. "Different kinds of events produce different wave patterns. We want to try to extract a wave pattern -- a special sound -- that matches our model from all of the noise in the LIGO data."

It takes massive amounts of computer power and data storage capacity to analyze the data against the gravitational wave models Duncan and his colleagues built. SUGAR is a collection of 80 computers, packing 320 CPUs of power and 640 Gigabytes of random access memory. SUGAR also has 96 terabytes of disk space on which to store the LIGO data.

It also takes a dedicated, high-speed fiber-optic network to transfer the data between Caltech and SU. To accomplish that, SU's Information Technology and Services (ITS) collaborated with NYSERNet to build a special pathway for the LIGO data on the high-speed fiber optic network that crisscrosses the United States. The one-gigabit pathway begins in the Physics Building and traverses SU's fiber-optic network to Machinery Hall and then to a network facility in downtown Syracuse, which the University shares with NYSERNet. From there, the pathway connects to NYSERNet's fiber-optic network and goes to New York City. In New York City, the pathway switches to the Internet2 high-speed network and traverses the country, ending in a computer room in Caltech.

Both the supercomputer and the high-speed network are expected to be up and running by the end of February. Once the data is transferred to SU from Caltech, Brown and his LSC colleagues will begin to listen to the "cosmic symphony." "Gravitational waves can teach us much about what is out there in the universe," Brown says. "We've never looked at Einstein's theory in this way."

LIGO is funded by the National Science Foundation and operated by Caltech and the Massachusetts Institute of Technology.

Adapted from materials provided by Syracuse University.