MARSBUGS: The Electronic Astrobiology Newsletter Volume 7, Number 7, 21 February 2000. Editors: Dr. David J. Thomas, Biology and Chemistry Division, Lyon College, Batesville, AR 72503-2317, USA. dthomas@lyon.edu Dr. Julian A. Hiscox, School of Animal and Microbial Sciences, University of Reading, Reading, RG6 6AJ, United Kingdom. J.A.Hiscox@reading.ac.uk Marsbugs is published on a weekly to quarterly basis as warranted by the number of articles and announcements. Copyright of this compilation exists with the editors, except for specific articles, in which instance copyright exists with the author/authors. While we cannot copyright our mailing list, our readers would appreciate it if others would not send unsolicited e-mail using the Marsbugs mailing list. The editors do not condone "spamming" of our subscribers. Persons who have information that may be of interest to subscribers of Marsbugs should send that information to the editors. E-mail subscriptions are free, and may be obtained by contacting either of the editors. Article contributions are welcome, and should be submitted to either of the two editors. Contributions should include a short biographical statement about the author(s) along with the author(s)' correspondence address. Subscribers are advised to make appropriate inquiries before joining societies, ordering goods etc. Back issues and Adobe Acrobat PDF files suitable for printing may be obtained from the official Marsbugs web page at http://www.lyon.edu/webdata/users/dthomas/marsbugs/marsbugs.html. The purpose of this newsletter is to provide a channel of information for scientists, educators and other persons interested in exobiology and related fields. This newsletter is not intended to replace peer- reviewed journals, but to supplement them. We, the editors, envision Marsbugs as a medium in which people can informally present ideas for investigation, questions about exobiology, and announcements of upcoming events. Astrobiology is still a relatively young field, and new ideas may come from the most unexpected places. Subjects may include, but are not limited to: exobiology and astrobiology (life on other planets), the search for extraterrestrial intelligence (SETI), ecopoeisis and terraformation, Earth from space, planetary biology, primordial evolution, space physiology, biological life support systems, and human habitation of space and other planets. --------------------------------------------------------------------- CONTENTS 1) LOCKHEED MARTIN PROPOSING TO JET PROPULSION LABORATORY TO STUDY DESIGN OPTIONS FOR NASA'S TERRESTRIAL PLANET FINDER MISSION Lockheed Martin Space Systems release 00-016 2) UW EXPERTS SQUELCH HOPE OF FINDING FOLKS ON THAT FINAL FRONTIER By Eric Sorensen 3) EARLY ALERT ON COMETS AND ASTEROIDS GETS EVEN FASTER--GRANT ENHANCES COMPUTATIONAL CAPABILITY OF MINOR PLANET CENTER Harvard-Smithsonian Center for Astrophysics release 00-06 4) LATVIAN RADIO TELESCOPE COULD BE USED FOR SETI--ASTRONOMER AIMS TO RESTORE TELESCOPE By Steven C. Johnson 5) SNOWBALL EARTH EPISODE 2.4 BILLION YEARS AGO WAS HARD ON LIFE, BUT GOOD FOR MODERN INDUSTRIAL ECONOMY, RESEARCH SHOWS California Institute of Technology release 6) NASA/FRENCH SATELLITE FOLLOWS FISH-FEEDING EDDIES JPL image advisory 7) NASA BEGINS BUILDING NEXT MISSION TO STUDY COMETS NASA release 00-26 8) NASA GIVES GO-AHEAD TO CORNELL-LED 2002 MISSION TO EXPLORE COMETS Cornell University News Services release 9) NEWS FROM THE COLUMBUS OPTICAL SETI OBSERVATORY By Stuart A. Kingsley 10) VETERAN GALILEO VENTURES TO VAST VOLCANIC VISTAS JPL release 11) GALILEO--COUNTDOWN TO IO By Ron Baalke 12) THIS WEEK ON GALILEO JPL release 13) NEXT THREE DAYS ON GALILEO JPL release 14) MARS POLAR LANDER MISSION STATUS JPL release 15) HAPPY BIRTHDAY STARDUST! By Ken Atkins 16) STARDUST STATUS REPORT JPL release --------------------------------------------------------------------- LOCKHEED MARTIN PROPOSING TO JET PROPULSION LABORATORY TO STUDY DESIGN OPTIONS FOR NASA'S TERRESTRIAL PLANET FINDER MISSION Lockheed Martin Space Systems release 00-016 4 February 2000 A team led by Lockheed Martin Space Systems has proposed to the Jet Propulsion Laboratory (JPL) to study several design options for NASA's Terrestrial Planet Finder (TPF) mission. TPF, a key mission in NASA's Origins Program, is targeted for launch in 2011 and will seek to identify Earth-like planets around nearby stars. "We're extremely proud as a company to be competing for this very important mission," said Dr. Domenick Tenerelli, Space Systems program manager for TPF. "A search for planets like our own addresses directly the fundamental question of origins and the search for a unified theory of life, and we're delighted to be able to propose to JPL ways to accomplish that mission." The Lockheed Martin team, which includes the University of Arizona and the Massachusetts Institute of Technology, is well suited to the technological challenges posed by the TPF mission. Space Systems built and integrated the Hubble Space Telescope (HST) at its Sunnyvale facility, and HST's ultra-quiet systems have direct application to TPF. NASA's Space Infrared Telescope Facility (SIRTF) spacecraft is currently under construction at Space Systems. The SIRTF Pointing and Control Reference System will operate at a temperature of 1.4 Kelvin, slightly cooler than the threshold required for TPF. Additionally, with JPL, Space Systems is designing and building the interferometer for NASA's Space Interferometry Mission. Team member Dr. Roger Angel of the University of Arizona, a MacArthur Fellowship award recipient, is pioneering the development of lightweight mirror systems (less than 15kg/m2) and optical designs consistent with the requirements of TPF. Team member Dr. David Miller of MIT has done groundbreaking research into the process of flying multiple spacecraft in formation that will be required for programs like TPF. The Terrestrial Planet Finder (TPF) will study all aspects of planets, from their formation and development in disks of dust and gas around newly forming stars, to the presence and features of those planets orbiting the nearest stars. It will investigate the numbers of planets at various sizes and places in their solar systems, and gauge their potential suitability as abodes for life. By combining the high sensitivity of space telescopes with the sharply detailed pictures from an interferometer, TPF will be able to reduce the glare of parent stars by a factor of more than 100,000 to see planetary systems as far away as 50 light years. TPF's spectroscopy will enable the measurement of size, temperature, and placement of planets as small as the Earth in the habitable zones of distant solar systems. This will allow atmospheric chemists and biologists to calculate relative amounts of gasses like carbon dioxide, water vapor, ozone and methane in planetary atmospheres and determine whether a planet might now or someday support life. In addition to studying planets around nearby mature stars like the sun, TPF will advance an understanding of how planets and their parent stars form. The disks of forming stars are a few earth-to-sun units (AU) across. TPF will study such structures on the scale of a few tenths of an AU to investigate how gaseous (Jupiter-like) and rocky (Earth-like) planets form out of disk material. By studying the heat glow from dust, ice and gasses such as hydrogen and carbon monoxide, TPF will investigate whether, as theory predicts, rocky planets form in warmer regions and gaseous planets in colder regions while a solar system is being born. TPF will also be able to examine many other astronomical objects where high resolution pictures, 100 times more detailed than those from Hubble, are critical to understanding astrophysical processes. Combining the sensitivity of the Next Generation Space Telescope (NGST) with detailed imaging will allow TPF to study the winds from dying stars that enrich the interstellar medium with life-enabling heavy atoms (like carbon and nitrogen). TPF will also enable astronomers to view the cores of quasars, and even the black hole at the center of our Milky Way galaxy. NASA's Origins Program follows the chain of events that began with the birth of the Universe at the Big Bang. It seeks to understand the entire process of cosmic evolution from the formation of chemical elements, galaxies, stars and planets, through the mixing of chemicals and energy that cradles life on Earth, to the earliest self-replicating organisms and the profusion of life. In short, Origins hopes to answer the fundamental question: Are we alone in the Universe? Lockheed Martin Space Systems, in Sunnyvale, CA, is a leading supplier of satellites and space systems to military, civil government and commercial communications organizations around the world. These spacecraft and systems have enhanced military and commercial communications; provided new and timely remote-sensing information; and furnished new data for thousands of scientists studying our planet and the universe. --------------------------------------------------------------------- UW EXPERTS SQUELCH HOPE OF FINDING FOLKS ON THAT FINAL FRONTIER By Eric Sorensen, Seattle Times 6 February 2000 It's a thought that grips most everyone who stares into the unfathomable depths of a star-speckled night: Is there anybody out there? The odds, say Peter Ward and Don Brownlee, are probably more remote than you think. Earth, they contend, is simply too special, the result of myriad physical conditions missing from most of the universe, with just enough time and other circumstances to let complicated life arise. "We consider it to be random chance and luck," said Brownlee, a University of Washington astronomer. "Mostly luck." Hence the title of their book, Rare Earth: Why Complex Life is Uncommon in the Universe, published this month (Copernicus, $27.50). [Get the full story at http://www.seattletimes.com/news/local/html98/rare_20000206.html] --------------------------------------------------------------------- EARLY ALERT ON COMETS AND ASTEROIDS GETS EVEN FASTER--GRANT ENHANCES COMPUTATIONAL CAPABILITY OF MINOR PLANET CENTER Harvard-Smithsonian Center for Astrophysics release 00-06 8 February 2000 Anxious astronomers, uncertain whether to run for cover or to tool up their telescopes, now at least will get their needed answers faster, thanks to a new high-speed computer at the world's asteroid and comet early-alert center. A grant from the Tamkin Foundation of Los Angeles, CA, has permitted the creation of a high-speed computer network for the Minor Planet Center, the international clearing house for astronomical information based at the Smithsonian Astrophysical Observatory (SAO), that will allow more rapid determination of the paths of newly discovered asteroids and comets, including those on possible crash courses with Earth. The Minor Planet Center, operated for the International Astronomical Union, serves the world scientific community by collecting, checking, and disseminating positional observations and orbital data for asteroids and comets. Tracking many thousands of objects simultaneously, the Center distributes initial and updated data by means of the Minor Planet Electronic Circulars (issued via email several times a day) and monthly consolidations of the data in the printed Minor Planet Circulars. The new "Tamkin Foundation Computing Network" will greatly enhance the level of service the Center can provide to astronomers around the world. Steven M. Tamkin, Executive Vice-President, presented his family foundation's contribution to Irwin I. Shapiro, Director of SAO, at an informal ceremony in Cambridge recently. An amateur astronomer with a deep interest in near-Earth asteroids and other objects with the potential to collide with the Earth, Mr. Tamkin noted that "This is the Foundation's first investment in nonmedical scientific research, and we look forward to a long and fruitful partnership in supporting the Center's work." The combination of observational and computational research is vital in astronomy, according to Brian Marsden, the Director of the Center and Associate Director of SAO's Planetary Sciences Division. "During the past few years new technology has completely revolutionized the way astronomers make their observations," says Marsden. "At numerous observatories around the world, computer programs examine an electronic image of the sky, immediately reduce the data for each asteroid or comet to a string of numbers, and then communicate those numbers to us at the Minor Planet Center," he says. "Our computer programs automatically establish which observations belong to the same asteroid or comet and make successive improvements to the orbital solutions that are then added to the database used to identify further observations," Marsden explains. "It is very rewarding for us that the Tamkin Foundation will support the computing technology that is integral to this kind of research." The Minor Planet center currently keeps tabs on the orbits of some 57,000 asteroids and 1,050 comets. In 1999 alone, there have so far been 25,000 new asteroids and 60 comets discovered. In his thanks, SAO Director Irwin Shapiro praised the Tamkin Foundation's willingness to branch out into new areas of scientific inquiry. Photos of the grant presentation ceremony are at http://cfa- www.harvard.edu/cfa/ep/tamkinpix.html For more information, contact: Dr. Brian Marsden, 617-495-7244, bmarsden@cfa.harvard.edu Ms. Amanda Preston, 617-495-7321, apreston@cfa.harvard.edu Mr. Steven Tamkin, Executive Vice President, The Tamkin Family Foundation, 2100 Sawtelle Blvd., Suite 201, Los Angeles, CA 90025- 6237, 310-457-4946, 76637.3505@compuserve.com For additional information on the Minor Planet Center see http://cfa- www.harvard.edu/iau/mpc.html. --------------------------------------------------------------------- LATVIAN RADIO TELESCOPE COULD BE USED FOR SETI--ASTRONOMER AIMS TO RESTORE TELESCOPE By Steven C. Johnson, Associated Press 13 February 2000 Astronomer Juris Zagars is a man with a mission: to get one of the former Soviet Union's most powerful telescopes, fallen into disrepair and forgotten by almost everyone else, back searching the heavens. The 50-year-old professor has gone at the task obsessively and almost single-handedly since he and his wife found the 600-ton instrument in a desolate forest in 1994, when Soviet troops finally left this small nation on the Baltic Sea after five decades of occupation... ...The radio telescope, dubbed Little Star, was a top-secret resource; the Soviets used it to monitor satellite communications between the United States and Western Europe... ...Little Star is one of the most powerful land-based radio telescopes ever made, capable of viewing far-off galaxies and participating in the search for intelligent life elsewhere in the universe, much as does the world's largest one-dish radio telescope in Arecibo, Puerto Rico. [For the complete story see http://dailynews.yahoo.com/h/ap/20000213/sc/exp_latvian_telescope_1.h tml] --------------------------------------------------------------------- SNOWBALL EARTH EPISODE 2.4 BILLION YEARS AGO WAS HARD ON LIFE, BUT GOOD FOR MODERN INDUSTRIAL ECONOMY, RESEARCH SHOWS California Institute of Technology release 14 February 2000 For the primitive organisms unlucky enough to be around 2.4 billion years ago, the first global freeze was a real wipeout, likely the worst in the history of life on Earth. Few of the organisms escaped extinction, and those that did were forced into an evolutionary bottleneck that altered the diversity of life for eons. But 2.4 billion years later, an unlikely winner has emerged from that first planetary deep-freeze, and it's none other than us modern industrial humans. New research from the California Institute of Technology reveals that the world's largest deposit of manganese (a component of steel) was formed by the cascade of chemical reactions caused when the planet got so cold that even the equators were icy--a condition now known as "Snowball Earth." In a special issue of the Proceedings of the National Academy of Sciences on global climatic change published February 14, Caltech geobiology professor Joe Kirschvink and his team show that the huge Kalahari Manganese Field in southern Africa was a consequence of a long Snowball Earth episode. Kirschvink, who originated the Snowball Earth concept more than a decade ago, says the new study explains how the drastic climatic changes in a Snowball Earth episode can alter the course of biological evolution, and can also account for a huge economic resource. According to Kirschvink and his team, the planet froze over for tens of millions of years, but eventually thawed when a greenhouse-induced effect kicked in. This warming episode led to the deposit of iron formations and carbonates, providing nutrients to the blue-green algae [cyanobacteria] that were waiting in the wings for a good feeding. The algae bloom during the melting period resulted in an oxygen spike, which in turn led to a "rusting" of the iron and manganese. This caused the manganese to be laid down in a huge 45- meter-thick deposit in the Kalahari to await future human mining and metallurgy. Today, about 80 percent of the entire world's known manganese reserves are found in that one field, and it is a major economic resource for the Republic of South Africa. The Snowball Earth's cascade of climatic chemical reactions also probably forced the living organisms of the time to mutate in such a way that they were protected from the excess oxygen. Because free radicals can cause DNA damage, the organisms adapted an enzyme known as the superoxide dismutase to compensate. Kirschvink points out that the enzyme and its evolutionary history are well known to biologists, but that a global climate change apparently has never been suggested as a cause of the enzyme's diversification. "To our knowledge, this is the first biochemical evidence for this adaptation," says Kirschvink, adding that the data shows that the adaptation can be traced back to the Snowball Earth episode 2.4 billion years ago. Kirschvink, his former doctoral student Dave Evans (now at the University of Western Australia in Perth), and Nicolas J. Beukes of Rand Afrikaans University proposed the Snowball Earth episode in a 1997 paper in Nature. Their evidence for the freeze of 2.4 billion years ago was based on their finding evidence of glacial deposits in a place in southern Africa that in ancient times was within 11 degrees of the equator, according to magnetic samples also gathered there. The other authors of the PNAS paper are Eric Gaidos of the Jet Propulsion Laboratory, who also holds an appointment in geobiology at Caltech; L. Elizabeth Bertani and Rachel E. Steinberger, both of the Division of Biology at Caltech; and Nicholas J. Beukes and Jans Gutzmer, both of Rand Afrikaans University in Johannesburg. The work was supported by the NASA National Astrobiology Institute. A detailed article on the Snowball Earth phenomenon was published in the January 2000 issue of Scientific American. Related links * Dr. Joseph Kirschvink http://www.gps.caltech.edu/faculty/kirschvink/ * Geobiology and Astrobiology at Caltech http://www.gps.caltech.edu/options/geobiology/geobio.html * Proceedings of the National Academy of Sciences http://intl.pnas.org/ * Jet Propulsion Laboratory (JPL) http://www.jpl.nasa.gov/ * The Division of Biology at Caltech http://www.caltech.edu/~biology/ * Rand Afrikaans University in Johannesburg http://www.rau.ac.za/ --------------------------------------------------------------------- NASA/FRENCH SATELLITE FOLLOWS FISH-FEEDING EDDIES JPL image advisory 14 February 2000 Some of the largest ocean eddies to form in recent years along the west coast of Alaska and Canada, bringing with them nutrients to feed a dwindling population of salmon and other marine life, are being tracked with satellite data from the joint NASA-French space agency TOPEX/Poseidon. An eddy is a water current that runs contrary to the main current. The large "Sitka" and "Haida" eddies, named for the town of Sitka, Alaska, and the native name for the Queen Charlotte Islands, British Columbia, Canada, form along the Alaskan Panhandle and Canadian west coast each year and drift into deeper waters to the west. The TOPEX/Poseidon satellite has tracked these and other eddies since the 1992-93 winter. Years with heavy El Niņo winds appear to produce particularly large eddies that can last for several years and replenish nutrient-starved regions of the ocean. Observations of the Haida Eddy by the Canadian research vessel J.P. Tully show that the eddies move fresh water, iron and nitrates from land to sea. "Our concern over the depletion of fish in this region makes altimeter measurements such as TOPEX/Poseidon data particularly important to understanding the formation and movement of these nutrient-rich eddies and how they influence salmon growth and other fisheries," said William Crawford of Fisheries and Oceans Canada at the Institute of Ocean Sciences. He and colleague Frank Whitney have been using TOPEX/Poseidon images produced by the University of Colorado to track large-scale eddies along the Pacific Northwest. They observed unusually high Sitka and Haida eddies in the ocean during the severe El Niņo of 1998. Both eddies were 30 centimeters (12 inches) higher than surrounding waters. "These eddies, which brought higher nutrient levels and a local resurgence of phytoplankton, became two of the largest observed," Crawford said. Phytoplankton is the minute plant life found in bodies of water. "With the subsidence of the Haida Eddy over the next year, we began to observe in the eddy a steady depletion of nutrients that are important to the food chain." The eddies usually drift westward and disappear within two years in deep waters off the Gulf of Alaska. These rotating masses of water can average up to a few hundred kilometers in diameter, forming along the coast within the northbound coastal current, Crawford said, and a large eddy can contain up to 5,000 cubic kilometers of water, which is about the volume of Lake Michigan. New measurements taken by TOPEX/Poseidon are available online at http://www-ccar.colorado.edu/~realtime/global-real-time_ssh Salinity and temperature measurements from the Canadian ship J. P. Tully have indicated that the subsurface water is fresher and warmer in this region than surrounding waters. Plans are under way to augment that data and to combine topographic measurements from space with new data on nutrient levels and fish abundance from ships to help fisheries predict annual food production. Crawford and Whitney will use TOPEX/Poseidon observations in the Gulf of Alaska to determine the average seasonal height of the sea surface and help determine the northward flow of surface currents along the Pacific coasts. The U.S./French mission, launched in 1992, is managed by the Jet Propulsion Laboratory for NASA's Earth Sciences Enterprise, Washington, DC. JPL is a division of the California Institute of Technology in Pasadena. --------------------------------------------------------------------- NASA BEGINS BUILDING NEXT MISSION TO STUDY COMETS NASA release 00-26 15 February 2000 NASA's Comet Nucleus Tour, or CONTOUR, mission this month took a giant step closer to its launch when the project received approval to begin building the spacecraft. Planned for a July 2002 launch, CONTOUR is expected to encounter Comet Encke in November 2003 and Comet Schwassmann-Wachmann-3 in June 2006. The mission has the flexibility to include a flyby of Comet d'Arrest in 2008 or an as-yet undiscovered comet, perhaps originating from beyond the orbit of Pluto. Such an unforeseen cometary visitor to the inner solar system, like Comet Hale-Bopp discovered in 1995, would present a rare opportunity to conduct a close-up examination of these mysterious, ancient objects which normally reside in the cold depths of interstellar space. The nucleus of a comet is its heart, believed by scientists to be a tiny irregular chunk of ice and rock. To date only one comet nucleus has ever been viewed by a spacecraft: Comet Halley in 1986. CONTOUR will fly past at least two comets and take higher resolution images than those of Halley. It will also collect and analyze gas and dust to reveal the comet's makeup, greatly improving our knowledge of key characteristics of comet nuclei and providing an assessment of their diversity. CONTOUR also will clear up the many mysteries of how comets evolve as they approach the Sun and their ices begin to evaporate. The CONTOUR spacecraft will fly by each comet at the peak of its activity when it's close to the Sun. During each encounter, the target comet will also be well situated in the night sky for astronomers worldwide to make concurrent observations from the ground. The spacecraft will fly by each comet at a distance of about 60 miles (100 kilometers). After successful completion of both the Preliminary Design Review and an independent Confirmation Assessment and the Confirmation Review at NASA Headquarters, the comet flyby project is well on its way toward completing the spacecraft design. The CONTOUR mission is managed for NASA by the Johns Hopkins University Applied Physics Laboratory, in Laurel, MD. The Principal Investigator is Dr. Joseph Veverka of Cornell University, NY. More information on CONTOUR is available at http://www.contour2002.org and http://discovery.nasa.gov --------------------------------------------------------------------- NASA GIVES GO-AHEAD TO CORNELL-LED 2002 MISSION TO EXPLORE COMETS Cornell University News Services release 16 February 2000 NASA has given the go-ahead for the Cornell University-led Comet Nucleus Tour, or CONTOUR, mission. The agency said the mission has passed a critical review and the building of the spacecraft can begin. Cornell will lead and direct the $158 million mission to conduct close-proximity comet flybys. The spacecraft is scheduled for launch in July 2002, with the precise launch date to be decided in the next year or two. The principal investigator on the mission is Joseph Veverka, professor of astronomy at Cornell and chair of the astronomy department. Other Cornell researchers on the team are Steven W. Squyres, professor of astronomy, who will interpret the geology of the comets; James Bell, assistant professor of astronomy, who will interpret the spectral maps of the comets; and Peter C. Thomas, senior research associate, who is a leading expert in determining the size and shape of irregular objects like comets. David Jarrett of NASA's Discovery Program, said, "After successful completion of both the preliminary design review and an independent confirmation assessment, the Contour team is well on its way toward completing the spacecraft design." The launching of CONTOUR is timed to encounter and study Comet Encke in November 2003 and Comet Schwassmann-Wachmann-3 in June 2006. The mission has the flexibility to include a flyby of Comet d'Arrest in 2008 or to retarget itself to approach an unforeseen cometary visitor to the inner solar system. Mission scientists are hopeful they will have the opportunity to study a newly discovered comet, such as Comet Hale-Bopp, which was discovered by amateur astronomers in 1995. The spacecraft, to be launched aboard a Delta rocket, will be outfitted with a solar array for power and a high-gain antenna for communication with Earth. The Contour spacecraft will venture about 30 million miles from Earth to study the comets. Building of the spacecraft at the Applied Physics Laboratory at Johns Hopkins University, which is managing the mission, begins this month. The nucleus of a comet is its heart, believed by scientists to be a tiny, irregular chunk of ice and rock. To date only one comet nucleus has ever been viewed with a spacecraft: Comet Halley in 1986. The spacecraft will fly past at least two comets and take far better pictures than those of Halley. It will also collect and analyze dust to reveal the comet's makeup, greatly improving our knowledge of key characteristics of comet nuclei and providing an assessment of their diversity. The mission also will clear up the many mysteries of how comets evolve as they approach the Sun and their ices begin to evaporate. The spacecraft will fly by each comet at the peak of its activity, close to the Sun. During each encounter, the target comet will also be well situated in the night sky for astronomers worldwide to make concurrent observations from the ground. The spacecraft will fly by each comet at a distance of about 100 kilometers (62 miles). Related World Wide Web sites The following sites provide additional information on this news release. Some might not be part of the Cornell University community, and Cornell has no control over their content or availability. *Comet Nucleus Tour http://www.contour2002.org *NASA Discovery Program http://discovery.nasa.gov --------------------------------------------------------------------- NEWS FROM THE COLUMBUS OPTICAL SETI OBSERVATORY By Stuart A. Kingsley 20 February 2000 1. Public Lecture on Optical SETI at Ohio University, Lancaster, on Sunday, February 27, 2000, and other upcoming OSETI talks in Central Ohio. 2. SPIE's Optical SETI III (January 22-24, 2000)--First Call for Papers. 3. HearMe chat rooms recently added to COSETI Web site. Please visit www.coseti.org for more information. Links will be found towards the bottom of the COSETI home page to all the items mentioned above. --------------------------------------------------------------------- VETERAN GALILEO VENTURES TO VAST VOLCANIC VISTAS JPL release 18 February 200 NASA's Galileo spacecraft is trying to go "three for three" as it attempts its third and closest flyby of Jupiter's fiery moon Io, the most volcanic body in the solar system. The spacecraft will dip to only 200 kilometers (124 miles) above Io's surface--roughly the distance between Los Angeles and San Diego--at 6:32 AM Pacific Standard Time on Tuesday, February 22. Galileo gathered a wealth of pictures and other scientific information during its flybys of Io in October and November of 1999. "Io's volcanoes are so active that the moon's surface is always changing, and with each flyby we get new and different observations," said Dr. Torrence Johnson, Galileo project scientist at NASA's Jet Propulsion Laboratory. "This time we expect to be able to observe the effects of the eruptions we saw in the October and November Io flybys." The Io flybys represent a classic case of "no pain, no gain," since Io orbits close to Jupiter in a region bombarded by radiation from the huge planet's radiation belts. That radiation can disrupt spacecraft systems or even knock out instruments, but mission planners believe potential gains in scientific knowledge outweigh the risks of the Io flybys. Nonetheless, the encounters were planned near the end of Galileo's extended missions, when the spacecraft has already returned volumes of pictures and information from Jupiter and its moons. "Although we gathered some great images and data during the previous Io flybys, the radiation did cause some problems, and we won't be surprised if that happens again this time," said Galileo Project Manager Jim Erickson of JPL. "Galileo has already survived more than twice the radiation it was designed to withstand, so we're keeping our fingers crossed that it will complete this encounter with flying colors." Galileo engineers often say that the spacecraft has "lived well past its warranty." Galileo entered orbit around Jupiter in December 1995. It was originally assigned to spend two years studying Jupiter, its moons and its magnetic environment. When that original mission ended in December 1997, it was followed by a two-year extended mission, which ended in January 2000. This Io flyby is part of an additional extension, called the Galileo Millennium Mission. Additional information about the Galileo mission is available at http://galileo.jpl.nasa.gov. JPL, a division of the California Institute of Technology in Pasadena, manages the Galileo mission for NASA's Office of Space Science, Washington, DC. --------------------------------------------------------------------- GALILEO--COUNTDOWN TO IO By Ron Baalke 19 February 2000 It is now 2 days, 10 hours to the Galileo spacecraft's next encounter with Jupiter's volcanic moon, Io. A special Countdown to Io home page is now available on the Galileo Home Page at http://www.jpl.nasa.gov/galileo/countdown/ Launched in October 1989, Galileo entered orbit around Jupiter in December 1995. The next encounter for Galileo is scheduled for Io on February 22, 2000. Referred to as Io 27, since this will occur on the 27th orbit since Galileo entered orbit around Jupiter, this encounter will be Galileo's closest ever flyby of Io. With a diameter of 3,630 km, Io is about the same size of our own Moon, and is the most volcanically active body in our solar system. On the upcoming encounter, the Galileo spacecraft will pass by the satellite at a distance of only 200 km (124 miles). Highlights of the Countdown to Io home page *A virtual flyby of Io with computer-generated approach images of Jupiter and Io displayed at the top of the home page. These images are all updated every 5 minutes in sync with the actual flyby by the spacecraft. *Latest Galileo status reports reporting on the Io 27 encounter. *Fact sheets and Europa, Callisto and Io. *Voyager 1 & 2 images of Callisto, Ganymede, Europa and Io. *Hubble Space Telescope images of the Galilean satellites. *Pioneer 10 & 11 images of Callisto, Ganymede, Europa and Io. --------------------------------------------------------------------- THIS WEEK ON GALILEO JPL release 14-18 February 2000 Galileo spends this week returning the remaining portions of science data stored on its onboard tape recorder during its previous two encounters. The data will be overwritten this coming weekend when the spacecraft flies past Io for the fourth time since arriving at Jupiter in December 1995. This Io flyby will be the closest-ever, with the spacecraft dipping to only 200 kilometers (124 miles) above the fiery surface. Because Io orbits in an area of very intense radiation from Jupiter, the possibility exists that Galileo spacecraft components may be affected, particularly since Galileo has already survived more than twice the radiation it was originally designed to withstand. Data playback is terminated on Friday, just prior to the spacecraft execution of a small flight path adjustment. Encounter commands start executing late Saturday night. The data returned this week come from an additional pass through the data stored on the tape recorder. The additional pass allows playback planners to return new data, and also allows replay of data lost in transmission to Earth, or reprocessing of data using different compression parameters. Ten observations are on this week's playback schedule. One is returned by the Fields and Particles instruments (Dust Detector, Energetic Particle Detector, Heavy Ion Counter, Magnetometer, Plasma Detector, and Plasma Wave instruments). Two are returned by the Near-Infrared Mapping Spectrometer (NIMS). Seven are returned by the Solid-State Imaging camera (SSI). The Fields and Particles instruments return the final portions of a 60-minute high resolution recording of the plasma, dust, and electric and magnetic fields in the vicinity of Europa. The measurements will allow scientists to refine and interpret estimates of Europa's induced magnetic field, the presence of which was detected in data received from Galileo during the actual spacecraft flyby of Europa last month. The fact that an induced magnetic field exists on Europa has provided the best evidence yet that Europa has a conducting layer beneath its surface. The most likely explanation for this layer is the presence of a salty liquid ocean beneath Europa's frozen surface. SSI follows suit with the return of images (one image per observation) of three of Jupiter's smaller moons: Amalthea, Thebe, and Metis. These images will provide the best resolution views of these moons, almost a factor of two better than previous best resolution images in the case of Amalthea and Metis. NIMS enters the playback picture with the return of a near-global observation of the hemisphere of Io that contains the volcanic region of Loki. SSI then returns a series of color images of the Loki region, followed by images of three other regions of Io. In the first observation, SSI captures a look at two unnamed giant volcanic calderas in Io's northern hemisphere. The next observation contains an image of the Culann volcanic region, and the final observation sees a region of Io's surface near the terminator (or imaginary line dividing night from day). NIMS closes out the playback schedule with the return of a regional map of Io's surface. Come back on Saturday, February 19 for the return of Today on Galileo and Gaileo's next daring encounter with fiery Io! For more information on the Galileo spacecraft and its mission to Jupiter, please visit the Galileo home page at one of the following URL's: http://galileo.jpl.nasa.gov http://www.jpl.nasa.gov/galileo --------------------------------------------------------------------- NEXT THREE DAYS ON GALILEO JPL release 19-21 February 2000 Galileo's intrepid flight controllers take the spacecraft back to Io in the next few days as part of the second encounter of the Galileo Millennium Mission, the extension to Galileo's mission at Jupiter. Dubbed as I27 ("I" for Io), the encounter is the 27th flyby of Galileo's orbital tour, which started back in June 1996 with Ganymede. This Io flyby will mark the fourth time the spacecraft has flown past Io since arriving at Jupiter in December 1995, and is the closest-ever approach, with a flyby altitude of only 200 kilometers (124 miles) above Io's fiery surface. That is the same distance at which Galileo flew over Europa in December 1997, and is about the same as the distance between Los Angeles and San Diego! As has been the case for recent encounters, Galileo's flyby of Io places the spacecraft at risk of being affected by Jupiter's intense radiation belts. Galileo's components have already survived more than twice the radiation they were originally designed to withstand, and any passage through the Jupiter system that can reach Io also adds significantly to the total radiation dose experienced by the spacecraft. The risk associated with this endeavor is well worth the promise of new information on Io and its unique status as the most volcanically active body in the solar system. The Io flyby is scheduled to occur on Tuesday morning at 5:47 AM PST [see Note 1]. Radio signals indicating that the flyby has occurred, however, won't be received on Earth until 45 minutes later, or at 6:32 AM PST, which is denoted as Earth Received Time (ERT). The time difference is due to the fact that the spacecraft is approximately 5.4 astronomical units (811 million kilometers, or 504 million miles, 1 astronomical unit is equal to the average distance between the Earth and the Sun) from Earth and it will take radio signals just over 45 minutes to travel between the spacecraft and Earth. Encounter commands for the Io flyby begin to execute late Saturday night at 8:00 PM PST (8:45 PM PST-ERT). They will continue to execute through mid-Wednesday when data playback will be initiated. Prior to the start of the encounter, the spacecraft performs standard maintenance on its onboard tape recorder. The majority of the observations performed during the encounter will be stored on this device for later processing and transmission to Earth. The encounter also features distant flybys of the other Galilean moons. Although no observing is done during those flybys, the only one close enough to mention is the flyby of Europa that occurs on Monday at 7:51 PM PST (8:36 PM PST-ERT) at a distance of 409,000 kilometers (254,000 miles). Around noon Sunday, Galileo's radio signal begins to pass through Jupiter's upper atmosphere on its way to Earth. The signal is weakened and refracted by the extremely tenuous atmosphere approximately 25,000 kilometers (15,500 miles) above Jupiter's cloud tops. The small changes in the signal will be measured by the Radio Science Team here on Earth, and will allow scientists to gain more knowledge of the structure and electron density of Jupiter's upper atmosphere. Approximately 12 hours later, the spacecraft passes behind Jupiter as seen from the Sun. The eclipse lasts just short of two hours. Late Sunday, the Fields and Particles instruments resume their survey of the Jovian magnetosphere. This survey has been performed from orbit to orbit and allows scientists to study the long-term variations of the inner portions of Jupiter's magnetosphere. The survey data also provide context for higher resolution recordings performed by the instrument suite. The Fields and Particles instruments are comprised of the Dust Detector, Energetic Particle Detector, Heavy Ion Counter, Magnetometer, Plasma Detector, and Plasma Wave instrument. Monday sees the first remote sensing observations of the encounter. The Photopolarimeter Radiometer (PPR) takes two observations of Jupiter's atmosphere. The polarimetric observations will allow scientists to learn more about the vertical cloud structure of Jupiter, including cloud particle shape and size. This particular pair of observations will provide the best PPR resolution from Galileo's mission to date. PPR is also the first to look at Io. Its first observation captures the dark side of the volcanic moon. The map will be used to describe nighttime thermal emissions on Io and will aid scientists in the development of heat flow models. Anticipating the flyby of Io early Tuesday morning, the Radio Science team begins to carefully measure changes in the frequency of Galileo's radio signal just after 8:32 PM PST-ERT on Monday. The changes are caused by Io's gravitational pull on the spacecraft. If this sounds familiar, it is because similar experiments have been conducted on each of the previous four Io flybys, with differences only in the spacecraft's flight path. Radio scientists will track these changes for 20 hours, centered on the point of closest approach to Io. The data will be added to the existing repository that provides the basis for a model of Io's gravity field and internal structure. Come back tomorrow for flyby day! Note 1. Pacific Standard Time (PST) is 8 hours behind Greenwich Mean Time (GMT). For more information on the Galileo spacecraft and its mission to Jupiter, please visit the Galileo home page at one of the following URL's: http://galileo.jpl.nasa.gov http://www.jpl.nasa.gov/galileo --------------------------------------------------------------------- MARS POLAR LANDER MISSION STATUS JPL release 16 February 2000 Radio scientists at NASA's Jet Propulsion Laboratory have made a detailed analysis of data taken by a radio telescope at Stanford University on January 4 and believe the suspect signal is more likely of terrestrial origin and not from Mars Polar Lander. Further analysis of data taken by radio telescopes in the Netherlands, Italy and at Stanford on February 8 has not yielded any signal from Mars Polar Lander. Extensive analysis of all data taken during the last few weeks is ongoing. "We saw something in the January 4 data that had all the earmarks of a signal and we felt we had to check it out. In parallel, we started to perform analysis to determine if the signal came from Mars," said Richard Cook, project manager for Mars Polar Lander at JPL. "Based on the latest results, it is unlikely that we will attempt to listen again." The Jet Propulsion Laboratory manages Mars Polar Lander for NASA's Office of Space Science, Washington, DC. Lockheed Martin Astronautics Inc., Denver, CO, is the agency's industrial partner for development and operation of the spacecraft. JPL is a division of the California Institute of Technology, Pasadena, CA. --------------------------------------------------------------------- HAPPY BIRTHDAY STARDUST! By Ken Atkins, Stardust project manager 7 February 2000 The Stardust spacecraft blasted into space a year ago on February 7, 1999. Its destination--Comet Wild 2 (pronounced "Vilt 2"). Its mission--to capture interstellar and comet particles before returning to Earth in 2006. Over the past year, the ship and its "sailors" have learned to voyage on the ocean of deep space. It is just now passing its farthest point from the sun (aphelion) on this leg of the journey. It takes radio signals, travelling at the speed of light, almost a half-hour to reach Earth after they leave the spacecraft. There have been "storms" to sail through. The first attempt to move from gyro-stabilized control of the celestial attitude to pure star- referencing, found a software "bug" that caused the spacecraft to invoke its automatic fault protection. This placed Stardust in a "safe" mode to allow the controllers to troubleshoot and fix the problem. When the ship invokes the safing routine, it shuts down all unnecessary activities, including its telecommunication with Earth, and turns to the sun to ensure the lifeblood of solar energy floods its batteries and electronics with electricity. When it deems all is well, it sets up a plan to contact us on Earth, tell us what happened, and let us tell it what to do next. This routine, while carefully designed to protect the spacecraft, is still an "anxiety event" for the crew back on Earth. It's a bit like the feeling when your teenager is late coming home, and you get no phone call. The anxiety builds fear until the dutiful signal comes through. "I'm here!" "I'm O.K.!" Stardust and its crew have navigated three more safing events, all involving data handling by on-board software. During this first year in space, Stardust has operated the Cometary and Interstellar Dust Analyzer (CIDA) and the Dust Flux Monitoring Instrument (DFMI). Both have worked well, but DFMI has a power supply with an oscillation. That means the crew has had to develop a way of compensating for this. Currently, the plan involves limiting its operating time and cycling it off and on. Testing of this technique will come late in the year. DFMI is currently "off." CIDA has collected data of some interest to the science team. Analysis is underway to determine if interstellar dust impacts occurred as the ship navigated "upwind" in the interstellar dust stream. With Stardust rounding the "mark" to sail back downwind toward Earth, the science team has turned the CIDA off. As Stardust turned toward home, the crew commanded Stardust to fire on-board rockets to achieve the precise course for the Earth-swingby next January. The ship performed flawlessly in completing the three required rocket burns. In addition, the sample-return capsule (SRC) housing the Aerogel collector has been unlatched. This is in preparation for deployment of the collector in late February. Deployment will mark the beginning of the attempt to "catch" interstellar particles to bring home. So, the adventure continues. It is bittersweet in that while Stardust sails on, its sister ships at Mars were lost. The trauma underscores the risks of voyaging into the unknown, attempting audaciously to know it. To know the unknown most often requires the birth pangs of failure. Earth's oceans are littered with the bones of the ships and sailors who brought us to the understanding of our planet we now enjoy. We sail its sky with the safety provided by the sacrifices of the Wrights, Lindberg, Doolittle, Yeager, Earhart, and many others. And we plunge into deep space on the shoulders of Newton, Kepler, Tsiolkovsky, Goddard, and Von Braun, with the physics of space and the fire of rockets. Stardust has yet to meet its destiny. The unknown "landfall" of Wild 2 waits for the dawn of 2004. Nevertheless, the ship is "spaceworthy." The design is robust. A year of flight has made crew and ship a team. We know each other better in the arena of spaceflight. While we mourn our lost ships at Mars, we increase our vigilance and resolve. We have sailed the year from Cape Canaveral to First Aphelion. I celebrate the spacecraft. I congratulate the crew. Sail on, Stardust! May the "wind" be at your back! Happy birthday! --------------------------------------------------------------------- STARDUST STATUS REPORT JPL release 18 February 2000 There were two Deep Space Network (DSN) tracking passes in the past week. All subsystems on board the spacecraft are performing normally. During the first DSN pass no telemetry was received due to interference from the Sun--the angular separation from the Sun is only 1.4 degrees. A weak carrier was observed and the DSN was able to occasionally lock onto the telemetry subcarrier but never long enough to provide telemetry data. Although no data was captured, the fact that the spacecraft was there and transmitting at the correct data rate indicated that the spacecraft was healthy. The second DSN pass provided data that confirmed the spacecraft was healthy. Commands were sent to the spacecraft to return the Command Loss Timer to its original value of nine days. The spacecraft, due to interference from the Sun, did not successfully receive these commands. They will be sent again during the next pass. Preparation for the Aerogel deployment on February 22 is continuing. The commands have been built and are in testing and review. The All-Stellar performance continues to be monitored. The fuel usage remains at less than 3 grams/day. Analysis of the high-rate attitude telemetry is ongoing. The Stardust Outreach team hosted the Southern California Space Explorer Teachers training workshop with other project personnel providing presentations on comets and the Stardust Project. Ken Atkins, the Stardust Project Manager released a special one-year Stardust launch anniversary announcement. For more information on the Stardust mission--the first ever comet sample return mission--please visit the Stardust home page at http://stardust.jpl.nasa.gov. --------------------------------------------------------------------- End Marsbugs Volume 7, Number 7