Universe Today

January 27, 2006March 24, 2012 by Fraser Cain

The Spacesuit Satellite

ISS astronaut Mike Finke spacewalks in a Russian Orlon spacesuit in 2004. Image credit: NASA Click to enlarge
One of the strangest satellites in the history of the space age is about to go into orbit. Launch date: Feb. 3rd. That’s when astronauts onboard the International Space Station (ISS) will hurl an empty spacesuit overboard.

The spacesuit is the satellite — “SuitSat” for short.

“SuitSat is a Russian brainstorm,” explains Frank Bauer of NASA’s Goddard Space Flight Center. “Some of our Russian partners in the ISS program, mainly a group led by Sergey Samburov, had an idea: Maybe we can turn old spacesuits into useful satellites.” SuitSat is a first test of that idea.

“We’ve equipped a Russian Orlon spacesuit with three batteries, a radio transmitter, and internal sensors to measure temperature and battery power,” says Bauer. “As SuitSat circles Earth, it will transmit its condition to the ground.”

Unlike a normal spacewalk, with a human inside the suit, SuitSat’s temperature controls will be turned off to conserve power. The suit, arms and legs akimbo, possibly spinning, will be exposed to the fierce rays of the sun with no way to regulate its internal temperature.

“Will the suit overheat? How long will the batteries last? Can we get a clear transmission if the suit tumbles?” wonders Bauer. These are some of the questions SuitSat will answer, laying the groundwork for SuitSats of the future.

SuitSat can be heard by anyone on the ground. “All you need is an antenna (the bigger the better) and a radio receiver that you can tune to 145.990 MHz FM,” says Bauer. “A police band scanner or a hand-talkie ham radio would work just fine.” He encourages students, scouts, teachers and ham radio operators to tune in.

For years, Bauer and colleagues at Goddard have been connecting kids on Earth with astronauts on the ISS through the ARISS program (Amateur Radio on International Space Station). “There’s a ham rig on the ISS, and the astronauts love talking to students when they pass over schools,” Bauer explains. ARISS is co-sponsoring SuitSat along with the Radio Amateur Satellite Corporation (AMSAT), the American Radio Relay League (ARRL), the Russian Space Agency and NASA.

When will SuitSat orbit over your home town?

Use Science@NASA’s J-Pass utility to find out. The online program will ask for your zip code?that’s all. Then it will tell you when the ISS is going to orbit over your area. (Be sure to click the “options” button and select “all passes.”) Because the ISS and SuitSat share similar orbits, predictions for one will serve for the other. Observers in the United States will find that SuitSat passes overhead once or twice a day?usually between midnight and 4 o’clock in the morning. At that time of day, SuitSat and the ISS will be in Earth’s shadow and, thus, too dark to see with the naked eye. You’ll need a radio to detect them.

“Point your antenna to the sky during the 5-to-10 minute flyby,” advises Bauer, and this is what you’ll hear:

SuitSat transmits for 30 seconds, pauses for 30 seconds, and then repeats. “This is SuitSat-1, RS0RS,” the transmission begins, followed by a prerecorded greeting in five languages. The greeting contains “special words” in English, French, Japanese, Russian, German and Spanish for students to record and decipher. (Awards will be given to students who do this. Scroll to the “more information” area at the end of this story for details.)

Next comes telemetry: temperature, battery power, mission elapsed time. “The telemetry is stated in plain language?in English,” says Bauer. Everyone will be privy to SuitSat’s condition. Bauer adds, “Suitsat ‘talks’ using a voice synthesizer. It’s pretty amazing.”

The transmission ends with a Slow Scan TV picture. Of what? “We’re not telling,” laughs Bauer. “It’s a mystery picture.” (More awards will be given to students who figure out what it is.)

Students and teachers who want to try this, but have no clue how to begin, should contact their local ham radio club. There are thousands of them around the country. Click here to find a club near you. “Hams are notoriously outgoing; most would be delighted to help students tune in to SuitSat,” believes Bauer.

Bauer expects SuitSat’s batteries to last 2 to 4 days. “Although longer is possible,” he allows. After that, SuitSat will begin a slow silent spiral into Earth’s atmosphere. Weeks or months later, no one knows exactly when, it will become a brilliant fireball over some part of Earth?a fitting end for a trailblazer.

Visit SuitSat.org for launch updates and sighting reports.

Original Source: NASA News Release

January 27, 2006March 24, 2012 by Fraser Cain

Rhea’s Impact Basins

Rhea’s two large impact basins are shown in this image. Image credit: NASA/JPL/SSI Click to enlarge
This close view of Rhea prominently shows two large impact basins on the ancient and battered moon. The great age of these basins is suggested by the large number of smaller craters that are overprinted within them.

Ejecta from the bright, relatively young crater seen in Crater Contrast spreads from the eastern limb.

Terrain visible in this view is on the side of Rhea (1,528 kilometers, or 949 miles across) that faces away from Saturn. North on Rhea is up and tilted 30 degrees to the left.

This enhanced color view was created by combining images taken using filters sensitive to ultraviolet, visible green and infrared light. The images were taken with the Cassini spacecraft narrow-angle camera on Dec. 23, 2005, at a distance of approximately 341,000 kilometers (212,000 miles) from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 42 degrees. The image scale is 2 kilometers (1 mile) 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 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 operations center is based at the Space Science Institute in Boulder, Colo.

For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov . The Cassini imaging team homepage is at http://ciclops.org .

Original Source: NASA/JPL/SSI News Release

January 26, 2006March 24, 2012 by Fraser Cain

Two Stars Kicked Out of the Milky Way

An artist’s conception of an exiled star speeding out of the milkyway. Image credit: Ruth Bazinet, CfA Click to enlarge
TV reality show contestants aren’t the only ones under threat of exile. Astronomers using the MMT Observatory in Arizona have discovered two stars exiled from the Milky Way galaxy. Those stars are racing out of the Galaxy at speeds of more than 1 million miles per hour – so fast that they will never return.

“These stars literally are castaways,” said Smithsonian astronomer Warren Brown (Harvard-Smithsonian Center for Astrophysics). “They have been thrown out of their home galaxy and set adrift in an ocean of intergalactic space.”

Brown and his colleagues spotted the first stellar exile in 2005. European groups identified two more, one of which may have originated in a neighboring galaxy known as the Large Magellanic Cloud. The latest discovery brings the total number of known exiles to five.

“These stars form a new class of astronomical objects – exiled stars leaving the Galaxy,” said Brown.

Astronomers suspect that about 1,000 exile stars exist within the Galaxy. By comparison, the Milky Way contains about 100,000,000,000 (100 billion) stars, making the search for exiles much more difficult than finding the proverbial “needle in a haystack.” The Smithsonian team improved their odds by preselecting stars with locations and characteristics typical of known exiles. They sifted through dozens of candidates spread over an area of sky almost 8000 times larger than the full moon to spot their quarry.

“Discovering these two new exiled stars was neither lucky nor random,” said astronomer Margaret Geller (Smithsonian Astrophysical Observatory), a co-author on the paper. “We made a targeted search for them. By understanding their origin, we knew where to find them.”

Theory predicts that the exiled stars were thrown from the galactic center millions of years ago. Each star once was part of a binary star system. When a binary swings too close to the black hole at the galaxy’s center, the intense gravity can yank the binary apart, capturing one star while violently flinging the other outward at tremendous speed (hence their technical designation of hypervelocity stars).

The two recently discovered exiles both are short-lived stars about four times more massive than the sun. Many similar stars exist within the galactic center, supporting the theory of how exiles are created. Moreover, detailed studies of the Milky Way’s center previously found stars orbiting the black hole on very elongated, elliptical orbits – the sort of orbits that would be expected for former companions of hypervelocity stars.

“Computer models show that hypervelocity stars are naturally made near the galactic center,” said theorist Avi Loeb of the Harvard-Smithsonian Center for Astrophysics. “We know that binaries exist. We know the galactic center holds a supermassive black hole. So, exiled stars inevitably will be produced when binaries pass too close to the black hole.”

Astronomers estimate that a star is thrown from the galactic center every 100,000 years on average. Chances of seeing one at the moment of ejection are slim. Therefore, the hunt must continue to find more examples of stellar exiles in order to understand the extreme environment of the galactic center and how those extremes lead to the formation of hypervelocity stars.

The characteristics of exiled stars give clues to their origin. For example, if a large cluster of stars spiraled into the Milky Way’s central black hole, many stars might be thrown out at nearly the same time. Every known hypervelocity star left the galactic center at a different time, therefore there is no evidence for a “burst” of exiles.

Hypervelocity stars also offer a unique probe of galactic structure. “During their lifetime, these stars travel across most of the Galaxy,” said Geller. “If we could measure their motions across the sky, we could learn about the shape of the Milky Way and about the way the mysterious dark matter is distributed.”

The first newfound exile, in the direction of the constellation Ursa Major, is designated SDSS J091301.0+305120. It is traveling out of the galaxy at a speed of about 1.25 million miles per hour and currently is located at a distance of about 240,000 light-years from the earth. The second exile, in the direction of the constellation Cancer, is designated SDSS J091759.5+672238. It is moving outward at 1.43 million miles per hour and currently is located about 180,000 light-years from the earth.

Both stars, although traveling at tremendous speeds through space, are located so far from the earth that their motion cannot be detected except with sophisticated astronomical instruments.

This research has been submitted to The Astrophysical Journal Letters for publication and will be available online at http://arxiv.org/abs/astro-ph/0601580. Authors on the paper are Brown, Geller, Scott Kenyon and Michael Kurtz (Smithsonian Astrophysical Observatory).

Headquartered in Cambridge, Mass., the Harvard-Smithsonian Center for Astrophysics (CfA) is a joint collaboration between the Smithsonian Astrophysical Observatory and the Harvard College Observatory. CfA scientists, organized into six research divisions, study the origin, evolution and ultimate fate of the universe.

Original Source: CfA News Release

January 26, 2006 by Fraser Cain

2005 Was the Hottest Year

2005 was the warmest year since the late 1800s. Image credit: NASA Click to enlarge
The year 2005 may have been the warmest year in a century, according to NASA scientists studying temperature data from around the world.

Climatologists at NASA’s Goddard Institute for Space Studies (GISS) in New York City noted that the highest global annual average surface temperature in more than a century was recorded in their analysis for the 2005 calendar year.

Some other research groups that study climate change rank 2005 as the second warmest year, based on comparisons through November. The primary difference among the analyses, according to the NASA scientists, is the inclusion of the Arctic in the NASA analysis. Although there are few weather stations in the Arctic, the available data indicate that 2005 was unusually warm in the Arctic.

In order to figure out whether the Earth is cooling or warming, the scientists use temperature data from weather stations on land, satellite measurements of sea surface temperature since 1982, and data from ships for earlier years.

Previously, the warmest year of the century was 1998, when a strong El Nino, a warm water event in the eastern Pacific Ocean, added warmth to global temperatures. However, what’s significant, regardless of whether 2005 is first or second warmest, is that global warmth has returned to about the level of 1998 without the help of an El Nino.

The result indicates that a strong underlying warming trend is continuing. Global warming since the middle 1970s is now about 0.6 degrees Celsius (C) or about 1 degree Fahrenheit (F). Total warming in the past century is about 0.8? C or about 1.4? F.

“The five warmest years over the last century occurred in the last eight years,” said James Hansen, director of NASA GISS. They stack up as follows: the warmest was 2005, then 1998, 2002, 2003 and 2004.

Over the past 30 years, the Earth has warmed by 0.6? C or 1.08? F. Over the past 100 years, it has warmed by 0.8? C or 1.44? F.

Current warmth seems to be occurring nearly everywhere at the same time and is largest at high latitudes in the Northern Hemisphere. Over the last 50 years, the largest annual and seasonal warmings have occurred in Alaska, Siberia and the Antarctic Peninsula. Most ocean areas have warmed. Because these areas are remote and far away from major cities, it is clear to climatologists that the warming is not due to the influence of pollution from urban areas.

Original Source: NASA News Release

January 26, 2006March 24, 2012 by Fraser Cain

Tethys and Tiny Atlas

The two moons Tethys and tiny Atlas. Image credit: NASA/JPL/SSI Click to enlarge
This view from Cassini contains not one, but two moons. Tethys is slightly overexposed so that the real target of this image, tiny Atlas, can be seen. Atlas is at image center, just outside the A ring.

A couple of faint ringlets are visible in the Encke Gap, right of center. Tethys is 1,071 kilometers (665 miles) wide; Atlas is a mere 32 kilometers (20 miles) wide.

The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Dec. 21, 2005, at a distance of approximately 2 million kilometers (1.2 million miles) from Tethys and 1.7 million kilometers (1.1 million miles) from Atlas. The image scale is 12 kilometers (7 miles) per pixel on Tethys.

For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov . The Cassini imaging team homepage is at http://ciclops.org .

Original Source: NASA/JPL/SSI News Release

January 26, 2006 by Fraser Cain

Life Doesn’t Change Terrain Much

The more we explore Mars, the more it looks like Earth. Image credit: NASA Click to enlarge
One of the paradoxes of recent explorations of the Martian surface is that the more we see of the planet, the more it looks like Earth, despite a very big difference: Complex life forms have existed for billions of years on Earth, while Mars never saw life bigger than a microbe, if that.

“The rounded hills, meandering stream channels, deltas and alluvial fans are all shockingly familiar,” said William E. Dietrich, professor of earth and planetary science at the University of California, Berkeley. “This caused us to ask: Can we tell from topography alone, and in the absence of the obvious influence of humans, that life pervades the Earth? Does life matter?”

In a paper published in the Jan. 26 issue of the journal Nature, Dietrich and graduate student J. Taylor Perron reported, to their surprise, no distinct signature of life in the landforms of Earth.

“Despite the profound influence of biota on erosion processes and landscape evolution, surprisingly,?there are no landforms that can exist only in the presence of life and, thus, an abiotic Earth probably would present no unfamiliar landscapes,” said Dietrich.

Instead, Dietrich and Perron propose that life – everything from the lowest plants to large grazing animals – creates a subtle effect on the land not obvious to the casual eye: more of the “beautiful, rounded hills” typical of Earth’s vegetated areas, and fewer sharp, rocky ridges.

“Rounded hills are the purest expression of life’s influence on geomorphology,” Dietrich said. “If we could walk across an Earth on which life has been eliminated, we would still see rounded hills, steep bedrock mountains, meandering rivers, etc., but their relative frequency would be different.”

When a NASA scientist acknowledged to Dietrich a few years ago that he saw nothing in the Martian landscape that didn’t have a parallel on Earth, Dietrich began thinking about what effects life does have on landforms and whether there is anything distinctive about the topography of planets with life, versus those without life.

“One of the least known things about our planet is how the atmosphere, the lithosphere and the oceans interact with life to create landforms,” said Dietrich, a geomorphologist who for more than 33 years has studied the Earth’s erosional processes. “A review of recent research in Earth history leads us to suggest that life may have strongly contributed to the development of the great glacial cycles, and even influenced the evolution of plate tectonics.”

One of the main effects of life on the landscape is erosion, he noted. Vegetation tends to protect hills from erosion: Landslides often occur in the first rains following a fire. But vegetation also speeds erosion by breaking up the rock into smaller pieces.

“Everywhere you look, biotic activity is causing sediment to move down hill, and most of that sediment is created by life,” he said. “Tree roots, gophers and wombats all dig into the soil and raise it, tearing up the underlying bedrock and turning it into rubble that tumbles downhill.”

Because the shape of the land in many locations is a balance between river erosion, which tends to cut steeply into a slope’s bedrock, and the biotically-driven spreading of soil downslope, which tends to round off the sharp edges, Dietrich and Perron thought that rounded hills would be a signature of life. This proved to be untrue, however, as their colleague Ron Amundson and graduate student Justine Owen, both of the campus’s Department of Environmental Science, Policy and Management, discovered in the lifeless Atacama Desert in Chile, where rounded hills covered with soil are produced by salt weathering from the nearby ocean.

“There are other things on Mars, such as freeze-thaw activity, that can break rock” to create the rounded hills seen in photos taken by NASA’s rovers, Perron said.

They also looked at river meanders, which on Earth are influenced by streamside vegetation. But Mars shows meanders, too, and studies on Earth have shown that rivers cut into bedrock or frozen ground can create meanders identical to those created by vegetation.

The steepness of river courses might be a signature, too, they thought: Coarser, less weathered sediment would erode into the streams, causing the river to steepen and the ridges to become higher. But this also is seen in Earth’s mountains.

“It’s not hard to argue that vegetation affects the pattern of rainfall and, recently, it has been shown that rainfall patterns affect the height, width and symmetry of mountains, but this would not produce a unique landform,” Dietrich said. “Without life, there would still be asymmetric mountains.”

Their conclusion, that the relative frequency of rounded versus angular landforms would change depending on the presence of life, won’t be testable until elevation maps of the surfaces of other planets are available at resolutions of a few meters or less. “Some of the most salient differences between landscapes with and without life are caused by processes that operate at small scales,” Perron said.

Dietrich noted that limited areas of Mars’ surface have been mapped at two-meter resolution, which is better than most maps of the Earth. He is one of the leaders of a National Science Foundation (NSF)-supported project to map in high resolution the surface of the Earth using LIDAR (LIght Detection And Ranging) technology. Dietrich co-founded the National Center of Airborne Laser Mapping (NCALM), a joint project between UC Berkeley and the University of Florida to conduct LIDAR mapping showing not only the tops of vegetation, but also the bare ground as if denuded of vegetation. The research by Dietrich and Perron was funded by NSF’s National Center for Earth-surface Dynamics, the NSF Graduate Research Fellowship Program and NASA’s Astrobiology Institute.

Original Source: UC Berkeley News Release

January 26, 2006May 6, 2012 by Fraser Cain

Icy Extrasolar Planet Discovered

An artist’s illustration shows the extrasolar planet orbiting a dim star. Image credit: NASA Click to enlarge
Using a relatively new planet-hunting technique that can spot worlds one-tenth the mass of our own, researchers have discovered a potentially rocky, icy body that may be the smallest planet yet found orbiting a star outside our solar system.

The discovery suggests the technique, gravitational microlensing, may be an exceptional technology for finding distant planets with traits that could support life.

“This is an important breakthrough in the quest to answer the question ‘Are we alone?'” said Michael Turner, assistant director for the National Science Foundation (NSF) mathematical and physical sciences directorate. “The team has discovered the most Earth-like planet yet, and more importantly, has demonstrated the power of a new technique that is sensitive to detecting habitable planets. It can probe a much greater portion of our galaxy and is complementary to other techniques.”

Located more than 20,000 light years away in the constellation Sagittarius, close to the center of our Milky Way galaxy, planet OGLE-2005-BLG-390Lb is approximately five-and-a-half times the mass of Earth.

Orbiting a star one-fifth the mass of the sun at a distance almost three times that of Earth’s orbit, the newly discovered planet is frigid: the estimated surface temperature is -364 degrees Fahrenheit (-220 degrees Celsius).

Although astronomers doubt this cold body could sustain organisms, researchers believe gravitational microlensing will bring opportunities for observing other rocky planets in the “habitable zones” of stars – regions where temperatures are perfect for maintaining liquid water and spawning life.

The discovery, authored by 73 collaborators from 32 institutions, appears in the Jan. 26 issue of the journal Nature.

OGLE (Optical Gravitational Lensing Experiment) project telescopes first observed the lensing event on July 11, 2005. In an attempt to catch microlensing events as they occur, OGLE scans most of the central Milky Way each night, discovering more than 500 microlensing events per year. But to detect the signature of low-mass planets, astronomers must observe these events much more frequently than OGLE’s one survey per night.

So, when OGLE detected the July 11 lensing, its early warning system alerted fellow astronomers across the globe to microlensing event OGLE-2005-BLG-390 (for the 390th galactic bulge OGLE discovered in 2005). At that point, though, no one knew a planet would emerge.

“The only way to realize the full scientific benefit of our observations is to share the data with our competition,” said co-author Bohdan Paczynski of Princeton University, who along with Andrzej Udalski of Warsaw University Observatory and their colleagues co-founded OGLE in 1997.

The telescopes of PLANET (Probing Lensing Anomalies NETwork) and RoboNet tracked the July 11 episode to completion, providing the data that confirmed the presence of a previously unknown planet. These telescopes collect observations more frequently in an attempt to detect the microlensing signature of planets.

“This discovery was possible because the sun never rises on the PLANET collaboration,” said lead author and PLANET researcher Jean-Philippe Beaulieu of the Institut d’Astrophysique de Paris, France. “The global nature of the PLANET collaboration was crucial for obtaining data throughout the 24-hour planetary signal,” he added.

Ironically, when preparing the final report, the researchers discovered that during its test runs, the new MOA (Microlensing Observations in Astrophysics) telescope, MOA-2, had taken additional measurements of the lensing event. The 6-foot (1.8-meter) aperture telescope has a wider field-of-view than the OGLE telescope, enabling it to observe 100 million stars many times per night. MOA-2 is one of several recent and future advancements that gravitational microlensing proponents hope will greatly increase the number of Earth-like planet discoveries.

OGLE also has plans to increase the field-of-view of its own telescope, and other microlensing groups are proposing to build a new telescope in South Africa. They have also proposed a space mission to see planets as small as Mars as well as free-floating planets that no longer orbit a host star.

“The new discovery provides a strong hint that low-mass planets may be much more common than Jupiters,” said co-author and PLANET researcher David Bennett of the University of Notre Dame. Most extrasolar planets found so far have been Jupiter-sized.

“Microlensing should have discovered dozens of Jupiters by now if they were as common as these five-Earth-mass planets. This illustrates the primary strength of the gravitational microlensing method: its ability to find planets of low-mass,” Bennett said.

Low-mass planets can yield signals that are too weak to detect with other methods. With microlensing, the signals of low-mass planets are rare but not weak. Thus, the rate of low-mass planet discoveries should increase dramatically if more microlensing events can be searched for planetary signals.

Original Source: NSF News Release

January 25, 2006March 24, 2012 by Fraser Cain

Prometheus and Dione

The Saturnian moons Prometheus and Dione. Image credit: NASA/JPL/SSI Click to enlarge
The ring moon Prometheus continues its work shaping the delicate F ring as Dione looks on. It is easy to see how Prometheus has an irregular, oblong shape, while Dione is quite round.

The rings are partly cut off by Saturn’s shadow at right. Prometheus is 102 kilometers (63 miles) wide; Dione is 1,123 kilometers (700 miles) wide.

The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Dec. 20, 2005, at a distance of approximately 2.5 million kilometers (1.6 million miles) from Dione and 2.2 million kilometers (1.4 million miles) from Prometheus. The image scale is 15 kilometers (9 miles) per pixel on Dione and 13 kilometers (8 miles) per pixel on Prometheus.

For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov . The Cassini imaging team homepage is at http://ciclops.org .

NASA/JPL/SSI News Release

January 25, 2006September 13, 2007 by Mark Mortimer

Book Review: On to Mars 2

Mars is the planet most like Earth. With this accreditation, it has remained one of the likeliest off-world places for people to colonize. There are the usual obstacles; long distance, no water, no infrastructure and a harsh environment. But with any fresh world, there are great opportunities for new technologies, new leadership and new societies. Governments of countries on Earth understandably have no mandate to establish colonies off-world and they’ve shown little progress. However, their constituents do have both the mandate and desire to pursue this captivating goal. Drawing on this desire is the organization called The Mars Society. Within are thousands of people who regularly contribute to our knowledge base on how people can successfully get to and profit from Mars. In their view, combining opportunities and desires into a concerted effort is one means of having that first human footfall on the Martian surface.

Lacking a government’s or business’ mandate to step onto Mars, the Mars Society is a ready outlet for people with this desire. Annual conferences allow individuals and teams to come together to spread the word. This book, and its enclosed CD, collect an expansive selection of contributions apparently from a number of conferences between the years 2000 and 2004. Many contributions are reports in scientific format that result directly from two of the Mars Society’s research encampments; the Mars Desert Research Station in Utah and the Flashline Arctic Research Station on Devon Island. At these sites, people with no astronaut training or experience but lots of desire can emulate the tasks and challenges of a hypothetical Mars site. In so doing, they can actively add knowledge today to contribute to tomorrow’s footfall.

Though the analogue sites are the basis for most of the papers, they don’t constrain the topics. Given the unique conditions of the sites (e.g. bare rock and hostile climate), people can assess particular aspects of a team on Mars. They can simulate and examine group dynamics amongst the participants, construct storage vaults using local material and measure dust ingress before gears grind to a halt. Contributors with other backgrounds and objectives also have reports. For them, sites may be backyards for greenhouse studies, desks and computers for rocket design or purely their own experience, such as with quality management. In essence, as we’re going to have to replicate many of the natural and human contrived processes, the Earth is just one big analogue.

With so much to choose from, there’s no wonder that the reports cover a broad selection of topics. This is the book’s undoing. All topics relate to Mars but this is the only common thread. Some get very technical, such as discussing bit rates and data packets for computer networks. Others are almost dreamy in their visions of leadership and government. Because of this, it is the authors’ passion that rises up to claim the common thread rather than the technical work or the target. As well, a contradiction arises. The book begins by claiming that NASA’s constituency driven mandate makes poor results by being random and entropic. Yet, the perception from reading this book is that these individual’s efforts are equally random and entropic. Organization and focus are lacking.

Nevertheless, if you have any interest in a human presence on Mars, this randomness shouldn’t and indeed won’t trip you up. This book will empower the average person to get off their duff and lend a hand. As is obvious, much work needs doing and there are many ways to contribute. The international range of authors and the many formats (e.g. reports, poetry and song) demonstrate the many possible routes. The annual conference, the thousands of supporters and this book show that volunteers need not work in isolation or without appreciation.

With Mars never leaving its nearby orbit and shimmering down on us at night, we’re always reminded of its proximity. And, we’ve proven our ability to go into space and walk on the surface of other realms. The book On to Mars – Volume 2 is a compilation by Frank Crossman and Robert Zubrin containing reports of ideas and results from people who are more than ready to put people on Mars. Their efforts speak loudly, and when that footfall first strikes, assuredly there will be a great chorus of cheers.

Review by Mark Mortimer

January 24, 2006March 29, 2013 by Fraser Cain

Opportunity Begins Its Third Year on Mars

Opportunity rover’s panorama of “Erebus Rim”. Image credit: NASA/JPL Click to enlarge
NASA’s Mars rovers, Spirit and Opportunity, have been working overtime to help scientists better understand ancient environmental conditions on the red planet. The rovers are also generating excitement about the exploration of Mars outlined in NASA’s Vision for Space Exploration.

The rovers continue to find new variations of bedrock in areas they are exploring on opposite sides of Mars. The geological information they have collected adds evidence about ancient Martian environments that included periods of wet, possibly habitable conditions.

“The extended journeys taken by the two rovers across the surface of Mars has allowed the science community to continue to uncover discoveries that will enable new investigations of the red planet far into the future.” said Mary Cleave, associate administrator for the Science Mission Directorate, NASA Headquarters.

NASA’s third mission extension for the rovers lasts through September 2006, if they remain usable that long. During their three-month primary missions, the rovers drove farther and examined more rocks than the prescribed criteria for success.

Opportunity begins its third year on Mars today. It is examining bedrock exposures along a route between “Endurance” and “Victoria” craters. Opportunity found evidence of a long-ago habitat of standing water on Mars.

On Jan. 3, Spirit passed its second anniversary inside the Connecticut-sized Gusev Crater. Initially, Spirit did not find evidence of much water, and hills that might reveal more about Gusev’s past were still mere bumps on the horizon. By operating eight times as long as planned, Spirit was able to climb up those hills, examine a wide assortment of rocks and find mineral fingerprints of ancient water.

While showing signs of wear, Spirit and Opportunity are still being used to their maximum remaining capabilities. On Spirit, the teeth of the rover’s rock abrasion tool are too worn to grind the surface off any more rocks, but its wire-bristle brush can still remove loose coatings. The tool was designed to uncover three rocks, but it exposed interiors of 15 rocks.

On Opportunity, the steering motor for the front right wheel stopped working eight months ago. A motor at the shoulder joint of the rover’s robotic arm shows symptoms of a broken wire in the motor winding. Opportunity can still maneuver with its three other steerable wheels. Its shoulder motor still works when given extra current, and the arm is still useable without that motor.

The rovers are two of five active robotic missions at Mars, which include NASA’s Mars Odyssey and Mars Global Surveyor and the European Space Agency’s Mars Express orbiters. The orbiters and surface missions complement each other in many ways. Observations by the rovers provide ground-level understanding for interpreting global observations by the orbiters. In addition to their own science missions, the orbiters relay data from Mars.

NASA’s Jet Propulsion Laboratory, Pasadena, Calif., a division of the California Institute of Technology, manages the Mars Exploration Rover, Odyssey and Global Surveyor projects for NASA’s Science Mission Directorate.

For images and information about the rovers and their discoveries on the Web, visit: http://www.nasa.gov/mars

Original Source: NASA/JPL News Release