MARSBUGS: The Electronic Astrobiology Newsletter Volume 6, Number 2, 3 February 1999. Editors: Dr. David Thomas, Department of Biological Sciences, University of Idaho, Moscow, ID, 83844-3051, USA. Marsbugs@aol.com or davidt@uidaho.edu. Dr. Julian Hiscox, Division of Molecular Biology, IAH Compton Laboratory, Berkshire, RG20 7NN, UK. Julian.Hiscox@bbsrc.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 via anonymous FTP at ftp.uidaho.edu/pub/mmbb/marsbugs or at the official Marsbugs web page at http://members.aol.com/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 out of 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) GALILEO BUZZES EUROPA By Tony Phillips 2) UW ASTRONOMY PROFESSOR'S STARDUST QUEST SET FOR LAUNCH SATURDAY University of Washington release 3) TODAY ON GALILEO JPL releases 4) MARS MISSION STATUS REPORTS JPL releases 5) INTERNATIONAL SOCIETY FOR GRAVITATIONAL PHYSIOLOGY (ISGP) MEETING ANNOUNCEMENT By Frank Sulzman 6) LIFE ON THE EDGE UPDATE By Tony Phillips 7) OPTICAL SETI UPDATE By Larry Klaes 8) ONLINE ASTROBIOLOGY-RELATED ARTICLES By David J. Thomas 9) ACRONYM LIST FOR SPACE AND ASTRONOMY By Mark Bradford ------------------------------------------------------------------ GALILEO BUZZES EUROPA By Tony Phillips From the NASA Space Science News home page 2 February 1999 On Sunday Galileo executed a close flyby of Europa for the last time during the current mission. JPL scientists reported yesterday that the Galileo spacecraft executed a close flyby of Europa on Sunday, passing a scant 894 miles above the surface of Jupiter's frozen moon. Early indications are that the maneuver was a success and that all scientific data were stored on the spacecraft's tape recorder for later playback. This latest flyby is the last of a series that began in late-1997 as part of the extended Galileo-Europa Mission (GEM). Europa intrigues scientists because of mounting evidence that a liquid ocean exists beneath its frozen surface. Although the moon's surface temperature is a chilly -260° F it's possible that warmth from a tidal tug of war with Jupiter and neighboring moons could be keeping large parts of Europa's ocean liquid. Tidal friction from Jupiter is also thought to be responsible for volcanic activity on Europa's neighbor Io. The picture [below, right] is an image from Europa's southern hemisphere. The brown, linear ridges extending across the scene are thought to be frozen remnants of cryo-volcanic activity. "Cryo-volcanoes" (cold volcanoes) occur when liquid or partially frozen water erupts onto the Europan surface, freezing instantly in the extremely low temperatures so far from our sun. A geologically older, smoother surface, bluish in tone, underlies the ridge system. The blue surface is composed of almost pure water ice, whereas the composition of the dark, brownish spots and ridges is not certain. One possibility is that they contain mineral salts in a matrix of high water content. Surf's up on Europa Galileo will continue to study Europa from a distance during the second half of the Galileo Europa Mission, but no additional close flybys are planned. However, NASA scientists have several projects in the planning stages to explore Europa from close range. One is the Europa Orbiter. It would use a radar sounder to study Europa's icy surface and attempt to determine the thickness of the ice and whether liquid water exists below the ice. Other instruments to study the surface and interior would include an imaging device with multiple filters to map the surface at a resolution of 100 meters and an altimeter to measure the topography and characterize the tidal response of the surface. The mission could launch in 2003 and would serve as a precursor to spacecraft that would actually send undersea explorers into the Europan oceans. Another intriguing proposal is the Europa Ice Clipper. The Ice Clipper is a flyby mission designed to obtain samples of Europa's surface by dropping hollow copper spheres onto the icy surface of the moon. After dropping the 10 kg spheres, the spacecraft would swing around and fly through the plume of surface material created by the impact. Surface debris would be captured by an aerogel collector similar to the one that will used by the Stardust spacecraft to capture particles from a comet. Like Stardust, the Ice Clipper would return its samples to Earth for analysis. (Editor's note: Stardust is scheduled for launch on February 6, 1999. It will rendezvous with Comet Wild-2 in the year 2004.) Other missions on the drawing board include Icepick, the Europa Ocean Observer, and the Europa Lander. So far only the Europa Orbiter has been funded. It will serve as an important precursor to future missions to Jupiter's enigmatic moon. The Jet Propulsion Laboratory, Pasadena, CA manages the Galileo mission for NASA's Office of Space Science, Washington, DC. [For more information on this subject see http://science.nasa.gov/newhome/headlines/ast02feb99_1.htm] ------------------------------------------------------------------ UW ASTRONOMY PROFESSOR'S STARDUST QUEST SET FOR LAUNCH SATURDAY University of Washington release 1 February 1999 It's a moment University of Washington astronomy professor Donald Brownlee has been awaiting for nearly two decades. If all goes as planned, that moment will arrive Saturday afternoon when a Boeing Delta II rocket, with "University of Washington" emblazoned on the side, sends a desk-sized spacecraft on a seven-year journey to rendezvous with a comet. Stardust is scheduled to launch from Cape Canaveral, FL, at 1:07 p.m. PST, and UWTV will provide live coverage. The mission, selected in 1995 by NASA as part of its Discovery series, aims to capture particles from comet Wild 2 (pronounced Vilt 2) and return them to Earth for analysis in laboratories at the UW, NASA and around the world. There's much to be learned, Brownlee said. "People have long suspected that comets played a role in the origin of life. No one really knows this because no one knows how life began. But we do know that comets are the most carbon-rich materials in the solar system, and we know they're full of organic compounds and they fall on the Earth all the time. Even now we have tens of thousands of tons of comet particles landing on the Earth every year," he said. Even though microscopic comet particles blanket open spaces such as parks and football stadiums every year, those particles don't tell the same story as ones collected from a comet such as Wild 2, Brownlee said. That's because Wild 2 only recently started orbiting close enough to the sun to make the mission feasible, so there hasn't been time enough for the sun's heat to destroy the characteristics of particles that have been preserved in a cryogenic deep freeze of space for billions of year. In 1980, Brownlee and NASA first considered a mission to capture comet particles. In that case, the target would have been Halley's comet, but the idea proved unworkable. Various technological advances and a bit of celestial luck changed that. Before 1974, Wild 2 traveled outside the orbit of Jupiter. But a close encounter with Jupiter that year altered the comet's trajectory, bringing it close enough to make Stardust possible. The spacecraft's encounter with the comet in early 2004 will take place just outside the orbit of Mars, 242 million miles from Earth on the other side of the sun. The mission is the first since Apollo 17 in 1972 to return extraterrestrial samples to Earth, and it is the first to bring back samples from beyond the orbit of the moon. Scientists will study the returned comet particles in the hope of understanding how life evolved on Earth. The planet probably was formed without water and without carbon or nitrogen, the building blocks of life. "The building blocks of life have long been thought to have come from further out in the solar system, out further away from the sun, and these would be materials from asteroids and comets," Brownlee said. Stardust will have journeyed 3.1 billion miles before it parachutes into the Utah desert in early 2006. During its encounter with Wild 2, a tennis-racquet shaped collector, sheathed with a wispy substance called aerogel, will be extended to collect comet grains when the spacecraft is within 100 miles of the comet's icy core. A high-power antenna will transmit close-up pictures, and sensitive equipment will gather data about the comet. The mission is a collaboration of the UW, NASA, NASA's Jet Propulsion Laboratory at the California Institute of Technology in Pasadena, Calif., and Lockheed Martin Astronautics in Denver. Other key members of the team are The Boeing Co., Germany's Max- Planck-Institut für extraterrestrische Physik, the NASA Ames Research Center and the University of Chicago. Brownlee expects information gathered by Stardust to shed light on how the solar system and the universe evolved. The mission also could have implications on astrobiology, the search for life beyond Earth. The UW this fall will begin the first doctoral program in astrobiology to train people to look for life on other celestial bodies, such as Mars and Europa, a moon of Jupiter. "From the astrobiology standpoint, we're interested in what kind of organic materials actually exist and how much there is and whether this played a role (in the formation of life)," Brownlee said. "Now this may be an impossible problem. We can study astrobiology and we can investigate how life might have formed, but no one was there taking notes when life formed. "You have things... before there was life and things after there was life but the real records aren't there," he said. "But by insight on this, you can at least look at what the starting materials were. So that's what Stardust is going to do, look at the starting materials, what was around in the solar system before life existed on Earth." The name "Stardust" seemed appropriate because of the nature of the project and the fact that people can relate to that name, Brownlee said. A recent radio interview ended with a few bars of the song "Woodstock" by Joni Mitchell, which includes the lyrics: "We are stardust, we are golden, we are 2 billion-year-old carbon." That's an appropriate thought, Brownlee said. "Comets are a vehicle that brings organic materials to the Earth. Many of the carbon atoms in our bodies were in comets early in the history of the solar system. So one of the bylines of the Stardust mission is that we are stardust. Our bodies are actually made of stardust." Science aside, there's a hint of romanticism about this mission. That's why, come Saturday, it won't be "Woodstock" but instead the soft strains of Hoagy Carmichael's "Stardust" drifting through the launch area. Additional information is available at http://stardust.jpl.nasa.gov or at http://www.washington.edu/newsroom/stardust/stardust.html ------------------------------------------------------------------ TODAY ON GALILEO JPL releases 30 January 1999 Today at 4 p.m. PST [see Note 1], Galileo starts the eighth encounter of the Galileo Europa Mission. The encounter features a close flyby of Jupiter's icy moon Europa, the ninth in a series that started with the last flyby of Galileo's primary mission. This flyby is also the last Europa flyby of the Galileo Europa Mission, and will occur tomorrow, Sunday, just after 6 PM PST. The spacecraft will be executing encounter commands through next Wednesday, but most of the encounter activity takes place on Sunday and Monday. During this time, the spacecraft is approximately 836 million kilometers (519 million miles) from Earth. At that distance, it takes radio signals approximately 46 1/2 minutes to travel from the spacecraft to Earth. To kick off the encounter, the fields and particles instruments resume their survey of the inner portions of Jupiter's vast magnetosphere. This survey has been repeated for almost every encounter of Galileo's mission at Jupiter, allowing scientists to study the long-term variations in the plasma, dust, and electric and magnetic fields that comprise the magnetosphere. The survey is scheduled to continue through Monday. Four remote sensing observations are performed today--two by the near-infrared mapping spectrometer and two by the ultraviolet spectrometer. Both near-infrared observations are designed to obtain measurements of the composition and thermal properties of Jupiter's atmosphere. Similar observations have been repeated during previous orbits, allowing the science community to map variations over time. By looking at the same location on Jupiter at different times, with different viewing geometries, it is possible to extract information on the properties of Jupiter's cloud layers. The depths of the different cloud layers, and their thickness, can be assessed in this way. The ultraviolet spectrometer takes the encounter's first look at Europa. Its first observation gathers measurements of Europa's surface that will give scientists clues as to how the surface has been affected by external phenomena such as meteors and high- energy particles that bombard the surface. In the second observation, the instrument will look for atmospheric emissions, which might be due to venting. Such outgassing events are an expected feature of ice volcanism. If detected, they would provide scientists with indirect evidence of internal activity within Europa, and would strengthen the case for liquid water there. 31 January 1999 Today is a very busy day for the spacecraft as it gathers science information describing Jupiter, Europa and Ganymede. Galileo flies over Europa's surface at 6:20 P.M. PST [see Note 1] at an altitude of 1439 kilometers (894 miles). Just after 9:00 P.M., the spacecraft will pass within 8.1 Jupiter radii (580,000 kilometers, 360,000 miles) of Jupiter's cloud tops. In addition, the spacecraft performs several turns to improve the view for some of the instruments' observations of Europa. The day begins with an observation of Jupiter by the photopolarimeter radiometer. This measurement is one of several that will be used to complete a polarimetry map of Jupiter's atmosphere. These polarimetry measurements will provide the science community with information on the texture and composition of Jupiter's atmosphere. This observation is followed by a series of six performed by the near-infrared mapping spectrometer. In sets of two, the observations alternate between gathering measurements of a hot spot and a region of Jupiter's Northern Temperate Belt. The ultraviolet spectrometer follows these observations with a look at Europa's surface, again searching for clues as to how the surface has been affected by external phenomena. Shortly after 8 am PST, the radio science team will begin careful tracking of the changes in the frequency of Galileo's radio signal. These changes are caused by Europa's gravitational pull on the spacecraft, and the resulting Doppler shift in Galileo's radio signals. The team will make these measurements for 20 hours, centered on the point of closest approach to Europa, and will use them to refine models of Europa's gravity field and internal structure. Mid-morning, the spacecraft performs its first turn of the day. The purpose of the turn is to allow the spacecraft's camera and other remote sensing instruments a view of Europa that is unobstructed by the spacecraft's booms and sunshield. The turn is necessitated by the geometry of this Europa flyby. About 30 minutes after the turn is complete, the photopolarimeter radiometer takes advantage of the improvement in viewing geometry to take a look at Europa on a global scale, taking another set of polarimetric measurements. A few minutes later, the instrument looks back at Jupiter and takes a second set of polarimetry measurements. A couple of hours later, the photopolarimeter radiometer looks back at Europa to gather more polarimetry measurements at regional resolutions. Shortly after the first photopolarimeter observation, the spacecraft camera takes the first of its 10 observations during close approach to Europa. The camera first looks at the Tegid crater region to characterize its shape and determine if it has a central dome feature similar to craters seen on other Galilean satellites. The camera then looks at a region of mottled or blotchy-looking terrain to determine if there is any relation between this type of terrain and well known triple bands. In a regional observation, the camera captures two images, the first of which will be used to fill in a gap in an already existing regional map of Europa. The second is used to obtain data to determine whether Europa is or is not in synchronous rotation, a question of importance in regard to the issue of tidal heating of that body. Another set of images taken by the camera will provide information on the structure of Europa's north polar plains, and an observation of Rhadamanthys Linea covers a region of the feature that may have been formed by cryo-volanic activity. The camera's next three observations capture data on Europa's Pwyll crater, a region of mottled terrain, and a region with specular or mirror-like appearance. Finally, the camera takes a series of images that will capture Europa's bright limb in a search for plumes. All of these observations are completed just prior to the spacecraft's closest approach to Europa. Following closest approach, the near-infrared mapping spectrometer performs two observations. Both of these are designed to search for a particular spectral signal that comes from ice in a hexagonal crystal structure. This structure may indicate relatively recent cryo-volcanism on the surface of Europa. The photopolarimeter radiometer takes the observing stage next, but turns its attention to Ganymede and gathers a set of polarimetry measurements of the satellite. This data will be used to fill in gaps in data sets obtained on previous orbits. Interleaved with these observations, for an hour surrounding the Europa flyby, the fields and particles instruments perform a high time resolution recording of measurements of the plasma, dust, and magnetic and electric fields surrounding Europa. These data will help scientists improve their understanding of the interaction between Europa and Jupiter's magnetosphere. Following the photopolarimeter radiometer's observation of Ganymede, the spacecraft performs the second turn of the day. This turn brings the spacecraft back to a more normal near-Earth pointed attitude. Following completion of the turn, the photopolarimeter radiometer takes another set of polarimetry measurements of Ganymede, and brings to an end today's observing schedule. For more information on the Galileo spacecraft and its mission to Jupiter, please visit the Galileo home page at http://www.jpl.nasa.gov/galileo Note 1. All times listed correspond to the Pacific Time zone (currently standard time) and spacecraft event time. Radio signals indicating that an event has occurred on the spacecraft reach the Earth 33 to 50 minutes later, depending on the time of year. Currently, this time is 46 1/2 minutes. Currently, Pacific Standard Time (PST) is 8 hours behind Greenwich Meridian Time (GMT). ------------------------------------------------------------------ MARS MISSION STATUS REPORTS JPL releases Friday 15 January 1999 Mars Polar Lander Mars Polar Lander continues in a healthy cruise state. During the past week, the flight team restarted normal attitude control processing using the star camera, successfully corrected a software bug in the on-board attitude control software that caused excessive thruster activity at attitude control mode changes, and slewed the spacecraft to the modified earth point orientation that is the nominal orientation for the start of its trajectory correction maneuver. As the result of the amount of flight team support required for these three activities, the first trajectory correction maneuver, previously scheduled for Monday, January 18th, has been put off until Thursday, January 21st, with very minimal effect on the fuel required. Future activities, in addition to the trajectory correction maneuver, will include spacecraft reorientations to assess stray light impacts on the star camera performance, and reconfiguring the spacecraft state for the long-term early cruise conditions. Mars Climate Orbiter Mars Climate Orbiter continues in a minimal activity cruise state with minimal Deep Space Network (DSN) tracking. The spacecraft is very healthy. Mars Global Surveyor Mars Global Surveyor (MGS) continues in the final weeks of aerobraking. With the end of aerobraking in sight, the weekly aerobraking control operations will deviate from the previous strategy of managing primarily the dynamic pressure, to a more intense assessment of the other factors contributing to the final orbit conditions. These include local mean solar time, orbital inclination, apoapsis altitude reduction increments, as well as dynamic pressure. Current aerobraking perform indicates a slightly earlier conclusion of aerobraking with the current estimate of walkout beginning on January 31st and termination of aerobraking on February 5th. At the time of this writing (1/15/99 @ 3 PM PST), MGS is in its 1079th orbit with an orbital period of 2.85 hours. The spacecraft is very healthy. Magnetometer/ electron reflectometer instruments' and radio science occultation data continue to be acquired. Magnetometer data acquisition will continue until the January 28th, which is the date of the southern most progression of the orbit's periapsis. 16 January 1999 Mars Polar Lander Mars Polar Lander is now in its nominal attitude for early cruise, while being tracked 2-3 times per day by 34 meter Deep Space Network (DSN) stations. Now under the control of its first housekeeping command sequence, the spacecraft continues to perform well. The first planned course correction, TCM-1, has been moved from January 18 to January 21, to allow sufficient time to complete software updates and reconfiguration of the lander needed for early cruise. At the beginning of this week, four principal tasks were identified by the flight team that needed to be accomplished prior to executing TCM-1. These are 1) restart stellar-aided attitude determination system and verify its performance, 2) install software patch to the lander to eliminate the autopilot anomaly identified last week, 3) slew lander to the baseline attitude for early cruise, and 4) complete transition of the software system to early cruise configuration. The first three tasks are complete, with the remaining task scheduled for completion early Tuesday morning of next week (January 19). Star camera processing and the lander's stellar-aided attitude determination software were reactivated on Wednesday morning (January 13), and functioned perfectly; at that time the spacecraft was still in its initial post-launch attitude. Over the course of the previous week, it was found that the lander's attitude knowledge, based solely on gyroscope computations, had drifted in error by only one degree, a testament to the extraordinary performance of the spacecraft's Honeywell ring-laser gyro system. In addition, an update to the thermal control software startup configuration file was performed to prevent any reoccurrence of the thermal control anomaly observed the previous week. On Thursday morning (January 14), the autopilot software patch was successfully loaded, and the autopilot restarted without incident. On Friday morning, the lander was commanded at 14:30 UTC to slew approximately 20º to bring the Earth further into the medium-gain antenna pattern, allowing high-data rate communications to be maintained well into February. This is the planned early cruise attitude. Preparations for TCM-1 are proceeding on schedule for a Jan. 21 execution date. Following this maneuver, the flight team will conduct a series of rotational maneuvers with the lander, designed to characterize the attitude envelope over which the star camera is presented with a sufficiently dark field of view allowing star pattern recognition. Mars Climate Orbiter Mars Climate Orbiter is now being monitored during a single tracking pass per day. The spacecraft's second housekeeping sequence was loaded Tuesday morning (January 12) and is now operating nominally. At that time the same thermal control configuration file described for the lander above was loaded onto the orbiter, to prevent any occurrence of an anomaly like that observed on the lander, due to the commonality in the two vehicle's software systems. Although the orbiter's second course correction, TCM-2, is scheduled for January 25, this event may well be moved, due to the additional work that was identified as needed prior to the lander's TCM-1. The flight team will establish the target date for TCM-2 on the orbiter early next week, following more assessment of the lander tasks that need to be accomplished following TCM-1. For more information on the Mars Surveyor 98 missions, please visit our web site at http://mars.jpl.nasa.gov/msp98 ------------------------------------------------------------------ INTERNATIONAL SOCIETY FOR GRAVITATIONAL PHYSIOLOGY (ISGP) MEETING ANNOUNCEMENT By Frank Sulzman 27 January 1999 The Annual Meeting of the International Society for Gravitational Physiology (ISGP) will be held in Orlando, FL, USA from 6-11 June, 1999. The meeting will consist of a series of half-day symposia, and free paper sessions. For more information, visit the ISGP web site http://www.isgp.org where you will find the Final Announcement and Call for Abstracts. Additionally, you can contact the President of ISGP, and organizer of the meeting, Dr. Michael Katovich (KATOVICH@cop.health.ufl.edu), the Chair of the ISGP Council of Trustees, Dr. Peter Norsk (pnorsk.damec@post.uni- c.dk), or Dr. Charles Fuller (cafuller@ucdavis.edu). ------------------------------------------------------------------ LIFE ON THE EDGE UPDATE By Tony Phillips A series of winter storms last week forced a one-week postponement of our latest assault on the White Mountain summit. We plan to try again tomorrow. Thanks to all of you who sent messages of encouragement last week! Meanwhile, ABC News has posted a nice web article on our activity, which you may view at this URL: Life in the Extreme by ABCNews.com's Lee Dye http://abcnews.go.com/sections/science/DyeHard/dye990127.html ------------------------------------------------------------------ OPTICAL SETI UPDATE By Larry Klaes Have you seen the latest news on Optical SETI? http://www.spaceviews.com/1999/01/20b.html http://planetary.org/news/articlearchive/headlines/1999/headln- 012099.html Dr. Stuart Kingsley would like to emphasize that, despite how it was written in the TPS news item, he is still very much active in OSETI work. http://www.coseti.org/tps_00.htm http://www.coseti.org/ ------------------------------------------------------------------ ONLINE ASTROBIOLOGY-RELATED ARTICLES By David J. Thomas Increasingly, scientific societies are placing articles from their journals online. While the full text of these articles is often restricted to members with subscriptions, some sites provide free access to back issues. Following are some articles that I found by chance that are available for free to the public. Most of the articles are available in HTML and PDF formats. An extensive list of online biological science journals is maintained by Scott Russell can be browsed at http://www.ou.edu/cas/botany-micro/ejournals/ H. James Cleaves and Stanley L. Miller. Oceanic protection of prebiotic organic compounds from UV radiation. PNAS 1998 95:7260- 7263. http://www.pnas.org/cgi/content/full/95/13/7260 Da-Fei Feng, Glen Cho, and Russell F. Doolittle. Determining divergence times with a protein clock: Update and reevaluation. PNAS 1997 94:13028-13033. http://www.pnas.org/cgi/content/full/94/24/13028 David K. Jacobs and David R. Lindberg. Oxygen and evolutionary patterns in the sea: Onshore/offshore trends and recent recruitment of deep-sea faunas. PNAS 1998 95:9396-9401. http://www.pnas.org/cgi/content/full/95/16/9396 Charles D. Keeling. Climate change and carbon dioxide: An introduction. PNAS 1997 94:8273-8274. http://www.pnas.org/cgi/content/full/94/16/8273 Igor A. Kozlov, Stefan Pitsch, and Leslie E. Orgel. Oligomerization of activated D- and L-guanosine mononucleotides on templates containing D- and L-deoxycytidylate residues. PNAS 1998 95:13448-13452. http://www.pnas.org/cgi/content/full/95/23/13448 Matthew Levy and Stanley L. Miller. The stability of the RNA bases: Implications for the origin of life. PNAS 1998 95:7933- 7938. http://www.pnas.org/cgi/content/full/95/14/7933 Richard S. Lindzen. Can increasing carbon dioxide cause climate change? PNAS 1997 94:8335-8342. http://www.pnas.org/cgi/content/full/94/16/8335 Richard A. Muller and Gordon J. MacDonald. Spectrum of 100-kyr glacial cycle: Orbital inclination, not eccentricity. PNAS 1997 94:8329-8334. http://www.pnas.org/cgi/content/full/94/16/8329 Kevin O. Pope, Steven L. D'Hondt, and Charles R. Marshall. Meteorite impact and the mass extinction of species at the Cretaceous/Tertiary boundary. PNAS Sep 15 1998; 95:11028-11029. http://www.pnas.org/cgi/content/full/95/19/11028 David S. Schimel, B. H. Braswell, and W. J. Parton. Equilibration of the terrestrial water, nitrogen, and carbon cycles. PNAS 1997 94:8280-8283. http://www.pnas.org/cgi/content/full/94/16/8280 David J. Thomson. Dependence of global temperatures on atmospheric CO2 and solar irradiance. PNAS 1997 94:8370-8377. http://www.pnas.org/cgi/content/full/94/16/8370 Carl Woese. The universal ancestor. PNAS 1998 95:6854-6859. http://www.pnas.org/cgi/content/full/95/12/6854 [Correction to the above article] http://www.pnas.org/cgi/content/full/95/16/9710/a ------------------------------------------------------------------ ACRONYM LIST FOR SPACE AND ASTRONOMY By Mark Bradford 31 January 1999 This list is offered as a reference for translating commonly appearing acronyms in the space-related newsgroups. If I forgot or botched your favorite acronym, please let me know! Also, if there's an acronym not on this list that confuses you, drop me a line, and if I can figure it out, I'll add it to the list. The canonical version of this list will now be the HTML form, available at http://www.users.uswest.net/~dinosaur/list.html. From that, I will generate the text form for USENET posting. Note that this is intended to be a reference for frequently seen acronyms, and is most emphatically not encyclopedic. If I incorporated every acronym I ever saw, I'd soon run out of disk space. The list will be posted at regular intervals, every 30 days. All comments regarding it are welcome; I'm reachable as dinosaur@uswest.net. Note that this just tells what the acronyms stand for -- you're on your own for figuring out what they mean. Note also that the total number of acronyms in use far exceeds what I can list; special-purpose acronyms that are essentially always explained as they're introduced are omitted. Further, some acronyms stand for more than one thing; as of Edition 3 of the list, these acronyms appear on multiple lines, unless they're simply different ways of referring to the same thing. Thanks to everybody who's sent suggestions since the first version of the list, and especially to Daniel Fischer (p515dfi@mpifr- bonn.mpg.de), who is maintaining a truly huge list (over 800 at last count) of acronyms and terms, mostly in German (which I read, fortunately), and Ken Hollis at NASA, who has sent me copies of NASA's own tomes of TLAs. PS: Strictly speaking, most of these are "abbreviations" rather than "acronyms"; pedantically, it's only an "acronym" if you make a word out of it, a la "laser." In practice, though, everybody calls 'em acronyms. A&A: Astronomy and Astrophysics AAO: Anglo-Australian Observatory AAS: American Astronomical Society AAS: American Astronautical Society AAVSO: American Association of Variable Star Observers ACE: Advanced Composition Explorer ACRV: Assured Crew Return Vehicle (or) Astronaut Crew Rescue Vehicle ADFRF: Ames-Dryden Flight Research Facility (now DFRC) (NASA) AGN: Active Galactic Nucleus AGU: American Geophysical Union AIAA: American Institute of Aeronautics and Astronautics AIPS: Astronomical Image Processing System AJ: Astronomical Journal ALEXIS: Array of Low Energy X-ray Imaging Sensors ALPO: Association of Lunar and Planetary Observers ALS: Advanced Launch System ANSI: American National Standards Institute AOA: Abort Once Around (Shuttle abort plan) AOA: Angle Of Attack AOCS: Attitude and Orbit Control System Ap.J: Astrophysical Journal APL: Applied Physics Laboratory (at Johns Hopkins) APM: Attached Pressurized Module (a.k.a. Columbus) APU: Auxiliary Power Unit ARC: Ames Research Center (NASA) ARC: Astrophysical Research Consortium ARTEMIS: Advanced Relay TEchnology MISsion ASA: Astronomical Society of the Atlantic ASI: Agenzia Spaziale Italiana ASP: Astronomical Society of the Pacific ASRM: Advanced Solid Rocket Motor ATDRS: Advanced Tracking and Data Relay Satellite ATLAS: Atmospheric Laboratory for Applications and Science ATM: Amateur Telescope Maker ATM: Apollo Telescope Mount (on Skylab) ATO: Abort To Orbit (Shuttle abort plan) AU: Astronomical Unit AURA: Association of Universities for Research in Astronomy AW&ST: Aviation Week and Space Technology (a.k.a. AvLeak) AXAF: Advanced X-ray Astrophysics Facility BAe: British Aerospace BATSE: Burst And Transient Source Experiment (on CGRO) BBXRT: Broad-Band X-Ray Telescope (ASTRO package) BDB: Big Dumb Booster BEM: Bug-Eyed Monster BH: Black Hole BIMA: Berkeley Illinois Maryland Array BIS: British Interplanetary Society BMDO: Ballistic Missile Defense Office (was SDIO) BNSC: British National Space Centre BTW: By The Way CARA: Center for Astrophysical Research in Antarctica C&T: Communications & Tracking CATS: Cheap Access To Space CCAFS: Cape Canaveral Air Force Station (now CCAS) CCAS: Cape Canaveral Air Station CCD: Charge-Coupled Device CCDS: Centers for the Commercial Development of Space CD-ROM: Compact Disc Read-Only Memory CFA: Center For Astrophysics CFC: ChloroFluoroCarbon CFF: Columbus Free Flyer CFHT: Canada-France-Hawaii Telescope CG: Center of Gravity CGRO: (Arthur Holley) Compton Gamma Ray Observatory (was GRO) CHARA: Center for High Angular Resolution Astronomy CIRRIS: Cryogenic InfraRed Radiance Instrument for Shuttle CIT: Circumstellar Imaging Telescope CM: Command Module (Apollo spacecraft) CM: Center of Mass CMBR: Cosmic Microwave Background Radiation CMCC: Central Mission Control Centre (ESA) CNES: Centre National d'Etude Spatiales CNO: Carbon-Nitrogen-Oxygen CNSR: Comet Nucleus Sample Return COBE: COsmic Background Explorer COMPTEL: COMPton TELescope (on CGRO) COSTAR: Corrective Optics Space Telescope Axial Replacement CRAF: Comet Rendezvous / Asteroid Flyby CRRES: Combined Release / Radiation Effects Satellite CSM: Command and Service Module (Apollo spacecraft) CSTC: Consolidated Space Test Center (USAF) CTIO: Cerro Tololo Interamerican Observatory CV: Cataclysmic Variable CXBR: Cosmic X-ray Background Radiation DC: Delta Clipper DCX: Delta Clipper eXperimental DDCU: DC-to-DC Converter Unit DDTE: Design, Development, Test, and Evaluation DFRC: Dryden Flight Research Center DFRF: Dryden Flight Research Facility (was ADFRF, now DFRC) DMSP: Defense Meteorological Satellite Program DOD: Department Of Defense (sometimes DoD) DOE: Department Of Energy DOT: Department Of Transportation DRS: Data Relay Satellite DRS: Direct Receiving Station DSCS: Defense Satellite Communications System DSN: Deep Space Network DSP: Defense Support Program (USAF/NRO) EAFB: Edwards Air Force Base ECS: Environmental Control System EDO: Extended Duration Orbiter EGRET: Energetic Gamma Ray Experiment Telescope (on CGRO) EJASA: Electronic Journal of the Astronomical Society of the Atlantic ELV: Expendable Launch Vehicle EMU: Extravehicular Mobility Unit EOS: Earth Observing System ER: Eastern Range (was ETR) ERS: Earth Resources Satellite (as in ERS-1) ESA: European Space Agency ESIS: European Space Information System ESO: European Southern Observatory ET: (Shuttle) External Tank ETLA: Extended Three Letter Acronym ETR: Eastern Test Range EUV: Extreme UltraViolet EUVE: Extreme UltraViolet Explorer EVA: ExtraVehicular Activity FAQ: Frequently Asked Questions FAST: Fast Auroral SnapshoT explorer FFT: Fast Fourier Transform FGS: Fine Guidance Sensors (on HST) FHST: Fixed Head Star Trackers (on HST) FIR: Far InfraRed FITS: Flexible Image Transport System FOC: Faint Object Camera (on HST) FOS: Faint Object Spectrograph (on HST) FRC: Flight Research Center (old name for DFRC) FRR: Flight-Readiness Review FTP: File Transfer Protocol FTS: Flight Telerobotic Servicer FUSE: Far Ultraviolet Spectroscopic Explorer FWHM: Full Width at Half Maximum FYI: For Your Information GAS: Get-Away Special GBT: Green Bank Telescope GCVS: General Catalog of Variable Stars GEM: Giotto Extended Mission GEM: Galileo Extended (or Europa) Mission GEO: Geosynchronous Earth Orbit GDS: Great Dark Spot GHRS: Goddard High Resolution Spectrograph (on HST) GIF: Graphics Interchange Format GLOMR: Global Low-Orbiting Message Relay GLOW: Gross Lift-Off Weight GMC: Giant Molecular Cloud GMRT: Giant Meter-wave Radio Telescope GMT: Greenwich Mean Time (also called UT) GOES: Geostationary Orbiting Environmental Satellite GOX: Gaseous OXygen GPC: General Purpose Computer GPS: Global Positioning System GR: General Relativity GRO: Gamma Ray Observatory (now CGRO) GRS: Gamma Ray Spectrometer (on Mars Observer) GRS: Great Red Spot GSC: Guide Star Catalog (for HST) GSFC: Goddard Space Flight Center (NASA) GTO: Geostationary Transfer Orbit HAO: High Altitude Observatory HD: Henry Draper catalog entry HEAO: High Energy Astronomical Observatory HeRA: Hermes Robotic Arm HF: High Frequency HGA: High Gain Antenna HLC: Heavy Lift Capability HLV: Heavy Lift Vehicle HMC: Halley Multicolor Camera (on Giotto) HOTOL: HOrizontal TakeOff and Landing (a proposed SSTO craft) HR: Hertzsprung-Russell (diagram) HRMS: High Resolution Microwave Survey HRI: High Resolution Imager (on ROSAT) HSP: High Speed Photometer (on HST) HST: Hubble Space Telescope HTHL: Horizontal Takeoff Horizontal Landing HTVL: Horizontal Takeoff Vertical Landing HUT: Hopkins Ultraviolet Telescope (ASTRO package) HV: High Voltage IAPPP: International Amateur/Professional Photoelectric Photometry IAU: International Astronomical Union IAUC: IAU Circular ICE: International Cometary Explorer IDA: International Dark-sky Association IDL: Interactive Data Language IGM: InterGalactic Medium IGY: International Geophysical Year IMHO: In My Humble Opinion IMO: International Meteor Organization IOTA: Infrared-Optical Telescope Array IOTA: International Occultation Timing Association IPS: Inertial Pointing System IR: InfraRed IRAF: Image Reduction and Analysis Facility IRAS: InfraRed Astronomical Satellite IRFNA: Inhibited Red Fuming Nitric Acid ISAS: Institute of Space and Astronautical Science (Japan) ISM: InterStellar Medium ISO: Infrared Space Observatory ISO: International Standards Organization ISPM: International Solar Polar Mission (now Ulysses) ISPP: In-Situ Propellant Production ISY: International Space Year IUE: International Ultraviolet Explorer IUS: Inertial Upper Stage JEM: Japanese Experiment Module (for SSF) JGR: Journal of Geophysical Research JILA: Joint Institute for Laboratory Astrophysics JPL: Jet Propulsion Laboratory JSC: Johnson Space Center (NASA) KAO: Kuiper Airborne Observatory KPNO: Kitt Peak National Observatory KSC: Kennedy Space Center (NASA) KTB: Cretaceous-Tertiary Boundary (from German) LANL: Los Alamos National Laboratory LaRC: Langley Research Center (NASA) LDEF: Long Duration Exposure Facility LEM: Lunar Excursion Module (a.k.a. LM) (Apollo spacecraft) LEO: Low Earth Orbit LeRC: Lewis Research Center (NASA) LEST: Large Earth-based Solar Telescope LFSA: List of Frequently Seen Acronyms (!) LGA: Low Gain Antenna LGM: Little Green Men LH: Liquid Hydrogen (also LH2 or LHX) LLNL: Lawrence-Livermore National Laboratory LM: Lunar Module (a.k.a. LEM) (Apollo spacecraft) LMC: Large Magellanic Cloud LN2: Liquid N2 (Nitrogen) LOX: Liquid OXygen LPO: La Palma Observatory LPV: Long Period Variable LRB: Liquid Rocket Booster LSR: Local Standard of Rest LTP: Lunar Transient Phenomenon M: Messier (as in M31, M13, M57, etcetera) MACRO: Monopoles, Astrophysics, and Cosmic Ray Observatory MB: Manned Base MCC: Mission Control Center MECO: Main Engine CutOff MMH: MonoMethyl Hydrazine MMT: Multiple Mirror Telescope MMU: Manned Maneuvering Unit MNRAS: Monthly Notices of the Royal Astronomical Society MOC: Mars Observer Camera (on Mars Observer) MOL: Manned Orbiting Laboratory MOLA: Mars Observer Laser Altimeter (on Mars Observer) MOMV: Manned Orbital Maneuvering Vehicle MOTV: Manned Orbital Transfer Vehicle MPC: Minor Planets Circular MPEC: Minor Planets Electronic Circular MRSR: Mars Rover and Sample Return MRSRM: Mars Rover and Sample Return Mission MSFC: (George C.) Marshall Space Flight Center (NASA) MTC: Man Tended Capability NACA: National Advisory Committee on Aeronautics (became NASA) NASA: National Aeronautics and Space Administration NASDA: NAtional Space Development Agency (Japan) NASM: National Air and Space Museum NASP: National AeroSpace Plane NBS: National Bureau of Standards (now NIST) NDV: NASP Derived Vehicle NERVA: Nuclear Engine for Rocket Vehicle Application NGC: New General Catalog NICMOS: Near Infrared Camera / Multi Object Spectrometer (HST upgrade) NIMS: Near-Infrared Mapping Spectrometer (on Galileo) NIR: Near InfraRed NIST: National Institute of Standards and Technology (was NBS) NLDP: National Launch Development Program NOAA: National Oceanic and Atmospheric Administration NOAO: National Optical Astronomy Observatories NORAD: NORth American aerospace Defense NRAO: National Radio Astronomy Observatory NRO: National Reconnaissance Office NS: Neutron Star NSA: National Security Agency NSF: National Science Foundation NSO: National Solar Observatory NSSDC: National Space Science Data Center NTR: Nuclear Thermal Rocket(ry) NTT: New Technology Telescope OAO: Orbiting Astronomical Observatory OCST: Office of Commercial Space Transportation OMB: Office of Management and Budget OMS: Orbital Maneuvering System OPF: Orbiter Processing Facility ORFEUS: Orbiting and Retrievable Far and Extreme Ultraviolet Spectrometer OSC: Orbital Sciences Corporation OSCAR: Orbiting Satellite Carrying Amateur Radio OSSA: Office of Space Science and Applications OSSE: Oriented Scintillation Spectrometer Experiment (on CGRO) OTA: Optical Telescope Assembly (on HST) OTHB: Over The Horizon Backscatter OTV: Orbital Transfer Vehicle OV: Orbital Vehicle PAM: Payload Assist Module PAM-D: Payload Assist Module, Delta-class PDS: Planetary Data System PI: Principal Investigator PLSS: Portable Life Support System PM: Pressurized Module PMC: Permanently Manned Capability PMIRR: Pressure Modulated InfraRed Radiometer (on Mars Observer) PMT: PhotoMultiplier Tube PPM: Positions and Proper Motions (catalog) PSF: Point Spread Function PSR: PulSaR PV: Photovoltaic PVO: Pioneer Venus Orbiter QSO: Quasi-Stellar Object RAS: Royal Astronomical Society RASC: Royal Astronomical Society of Canada RCI: Rodent Cage Interface (for SLS mission) RCS: Radar Cross Section RCS: Reaction Control System REM: Rat Enclosure Module (for SLS mission) RF: Radio Frequency RFI: Radio Frequency Interference RFNA: Red Fuming Nitric Acid RIACS: Research Institute for Advanced Computer Science RMS: Remote Manipulator System RNGC: Revised New General Catalog ROSAT: ROentgen SATellite ROUS: Rodents Of Unusual Size (I don't believe they exist) RSN: Radio SuperNova RSN: Real Soon Now RTG: Radioisotope Thermoelectric Generator RTLS: Return To Launch Site (Shuttle abort plan) SAA: South Atlantic Anomaly SAGA: Solar Array Gain Augmentation (for HST) SAMPEX: Solar Anomalous and Magnetospheric Particle EXplorer SAO: Smithsonian Astrophysical Observatory SAR: Search And Rescue SAR: Synthetic Aperture Radar SARA: Satellite pour Astronomie Radio Amateur SAREX: Search and Rescue Exercise SAREX: Space Amateur Radio Experiment SAS: Space Activity Suit SAS: Space Adaptation Syndrome SAT: Synthetic Aperture Telescope S/C: SpaceCraft SCA: Shuttle Carrier Aircraft SCT: Schmidt-Cassegrain Telescope SDI: Strategic Defense Initiative SDIO: Strategic Defense Initiative Organization (now BMDO) SEDS: Students for the Exploration and Development of Space SEI: Space Exploration Initiative SEST: Swedish ESO Submillimeter Telescope SETI: Search for ExtraTerrestrial Intelligence SID: Sudden Ionospheric Disturbance SIR: Shuttle Imaging Radar SIRTF: Space (formerly Shuttle) InfraRed Telescope Facility SL: (Comet) Shoemaker-Levy SL: SpaceLab SLAR: Side-Looking Airborne Radar SLC: Space Launch Complex SLS: Space(lab) Life Sciences SMC: Small Magellanic Cloud SME: Solar Mesosphere Explorer SMEX: SMall EXplorers SMM: Solar Maximum Mission SN: SuperNova (e.g., SN1987A) SNR: Signal to Noise Ratio SNR: SuperNova Remnant SNU: Solar Neutrino Units SOFIA: Stratospheric Observatory For Infrared Astronomy SOHO: SOlar Heliospheric Observatory SPAN: Space Physics and Analysis Network SPDM: Special Purpose Dextrous Manipulator SPOT: Satellite Pour l'Observation de la Terre SPS: Solar Power Satellite SR: Special Relativity SRB: Solid Rocket Booster SRM: Solid Rocket Motor SSF: Space Station Fred (er, Freedom) (Superseded by ISSA) SSI: Solid-State Imager (on Galileo) SSI: Space Studies Institut SSME: Space Shuttle Main Engine SSPF: Space Station Processing Facility SSPS: Sky Survey Prototype System SSRMS: Space Station Remote Manipulator System SSRT: Single Stage Rocket Technology SST: Spectroscopic Survey Telescope SST: SuperSonic Transport SSTO: Single Stage To Orbit STIS: Space Telescope Imaging Spectrometer (to replace FOC and GHRS) STS: Shuttle Transport System (or) Space Transportation System STScI: Space Telescope Science Institute STSDAS: Space Telescope Science Data Analysis System SWAS: Submillimeter Wave Astronomy Satellite SWF: ShortWave Fading TAL: Transatlantic Abort Landing (Shuttle abort plan) TAU: Thousand Astronomical Unit (mission) TCS: Thermal Control System TDRS: Tracking and Data Relay Satellite TDRSS: Tracking and Data Relay Satellite System TEA: Torque Equilibrium Attitude TES: Thermal Emission Spectrometer (on Mars Observer) TIROS: Television InfraRed Observation Satellite TLA: Three Letter Acronym TOMS: Total Ozone Mapping Spectrometer TOPS: Toward Other Planetary Systems TPS: Thermal Protection System TSS: Targeted Search System TSS: Tethered Satellite System TSTO: Two Stage To Orbit (also 2STO) UARS: Upper Atmosphere Research Satellite UBM: Unpressurized Berthing Mechanism UDMH: Unsymmetrical DiMethyl Hydrazine UFO: Unidentified Flying Object UGC: Uppsala General Catalog UHF: Ultra High Frequency UIT: Ultraviolet Imaging Telescope (Astro package) UKST: United Kingdom Schmidt Telescope USAF: United States Air Force USMP: United States Microgravity Payload UT: Universal Time (a.k.a. GMT, or Zulu Time; cf UTC) UTC: Coordinated Universal Time (subtly different from UT) UV: UltraViolet UVS: UltraViolet Spectrometer VAB: Vehicle Assembly Building (formerly Vertical Assembly Building) VAFB: Vandenberg Air Force Base VEEGA: Venus-Earth-Earth Gravity Assist (Galileo flight path) VHF: Very High Frequency VLA: Very Large Array VLBA: Very Long Baseline Array VLBI: Very Long Baseline Interferometry VLF: Very Low Frequency VLT: Very Large Telescope VMS: Vertical Motion Simulator VOIR: Venus Orbiting Imaging Radar (superseded by VRM) VPF: Vertical Processing Facility VRM: Venus Radar Mapper (now called Magellan) VTHL: Vertical Takeoff Horizontal Landing VTVL: Vertical Takeoff Vertical Landing WD: White Dwarf WFF: Wallops Flight Facility WFPC: Wide Field / Planetary Camera (on HST) WFPCII: Replacement for WFPC WIYN: Wisconsin / Indiana / Yale / NOAO telescope WR: Western Range (was WTR) WSF: Wake Shield Facility WSMR: White Sands Missile Range WTR: Western Test Range WUPPE: Wisconsin Ultraviolet PhotoPolarimter Experiment (Astro package) XMM: X-ray Multi Mirror XUV: eXtreme UltraViolet YSO: Young Stellar Object ------------------------------------------------------------------ End Marsbugs Vol. 6, No. 2