MARSBUGS: The Electronic Astrobiology Newsletter Volume 6, Number 5, 2 March 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) MARS GLOBAL SURVEYOR READY TO BEGIN FULL MAPPING MISSION JPL release 2) MARS SURVEYOR OPERATIONS PROJECT STATUS REPORT OVERVIEWS Prepared by the Mars Surveyor operations project manager 3) MARS GLOBAL SURVEYOR STATUS REPORT JPL release 4) MARS GLOBAL SURVEYOR AEROBRAKING PHASE IMAGE SET AVAILABLE JPL release 5) LIFE ON THE EDGE UPDATE By Tony Phillips 6) NASA/NCI BIOSIGNATURES WORKSHOP NASA release ------------------------------------------------------------------ MARS GLOBAL SURVEYOR READY TO BEGIN FULL MAPPING MISSION JPL release 22 February 1999 NASA's Mars Global Surveyor spacecraft will begin its primary mapping mission within the next two weeks, following a successful firing of its main engine at 2:20 PM Pacific time on Feb. 19 to fine-tune its path around the red planet into a nearly circular, Sun-synchronous orbit. The final "transfer to mapping orbit" burn lowered Global Surveyor's closest approach over Mars from 405 kilometers (253 miles) to approximately 367 kilometers (229 miles). Later this week, the flight team will turn on, focus and calibrate the spacecraft's camera and power up several other science instruments, including the thermal emission spectrometer and laser altimeter. "Reaching our mapping orbit has been a long time coming for all involved. We are delighted to finally be able to do this mission as it was designed, in the proper mapping orbit with all the instruments working at their full potential," said Dr. Arden Albee, the Mars Global Surveyor project scientist at the California Institute of Technology, Pasadena, CA. The mapping orbit was designed so that Surveyor passes over a given part of Mars at the same local time each orbit. At about 2 PM local Mars time, the spacecraft will cross the equator flying northward on the daytime side and about 2 AM, it will cross the equator flying southward on the nighttime side. This timing is essential for effective interpretation of atmospheric and surface measurements, because it allows scientists to separate local daily variations from longer-term seasonal and annual trends. "We still have a few minor adjustments to fine-tune the orbit during the next few weeks. Our plan at this point is to conduct the first three one-week mapping cycles with Surveyor's high-gain communication antenna in the stowed position. After we have these first mapping cycles completed, we plan to deploy the antenna and continue mapping in that configuration," said Glenn E. Cunningham, deputy director of the Mars Exploration Program at NASA's Jet Propulsion Laboratory (JPL), Pasadena, CA. Launched in November 1996 and in Mars orbit since September 1997, Mars Global Surveyor carries a dish-shaped high-gain antenna that will be deployed on a 2-meter-long (6.6-foot) boom. The antenna was stowed during launch and the early orbital phase at Mars to reduce the chances of it being contaminated by the exhaust plume from the spacecraft's main engine. During deployment, the boom is pushed outward by a powerful spring. A damper mechanism cushions the force of the spring and limits the speed of the deployment, somewhat like an automobile shock absorber or the piston-like automatic closer on a screen door. Last year, engineers became aware of problems with similar damper devices on deployable structures such as solar panels on other spacecraft. "Until we deploy the antenna, we must turn the entire spacecraft periodically to transmit data to Earth," Cunningham explained. "This means that we have to stop acquiring science data. The advantage of deploying the high-gain antenna is that we can then use its gimbals to point the antenna at Earth and send science data back at the same time the instruments are pointed at Mars." The first phase of the primary mapping mission is scheduled to begin on March 8. The deployment of high gain antenna is currently scheduled for March 29, pending approval by NASA Headquarters officials in mid-March. Mars Global Surveyor is the first mission in a long-term program of Mars exploration known as the Mars Surveyor Program that is managed by JPL for NASA's Office of Space Science, Washington, DC. JPL's industrial partner is Lockheed Martin Astronautics, Denver, CO, which developed and operates the spacecraft. JPL is a division of the California Institute of Technology. Further information about the mission, including a link to the "Top 10" images of Mars returned by Global Surveyor so far, is available on the Internet at http://mars.jpl.nasa.gov/mgs/ ------------------------------------------------------------------ MARS SURVEYOR OPERATIONS PROJECT STATUS REPORT OVERVIEWS Prepared by the Mars Surveyor operations project manager NASA Jet Propulsion Laboratory 19 February 1999 Mars Global Surveyor Mars Global Surveyor has completed its two-week gravity calibration period and has successfully executed a 22 m/s bipropellant maneuver to transfer to the mapping orbit orbital parameters on Friday afternoon (Feb 19). Earlier in the week, solid state recorder 2A apparently shut off by itself. Power cycling restored power consumption and functional testing of the unit will be accomplished later today. Otherwise, the spacecraft is performing normally. The coming week will see a flight software update for mapping and a one-day operational test of the mapping (nadir panel toward the planet) orientation. Mars Climate Orbiter Mars Climate Orbiter continued in semi-quiet cruise operations during the past week. Additional diagnostic telemetry from Inertial Measurement Unit (IMU)-A was downlinked last week in further support of the investigation into noise characteristics of the ring-laser gyro control loops. Further testing is underway by the manufacturer to characterize the circumstances in which the noise phenomenon is observed and to identify its cause. Commands were also sent to the spacecraft to obtain some specialized telemetry designed to map the unused space in the telemetry buffer. These maps are being used to formulate a "housekeeping" strategy for managing the buffer free space, limiting its fragmentation. On Tuesday, February 16, a simple test of the UHF transceiver was performed. With the orbiter in its cruise attitude, the transceiver was powered on and commanded into its nominal receive mode, in which it begins transmitting short "ping" waveforms of 150 ms duration every 3 seconds The transceiver was powered for approximately 2 hr; the X-band link with real-time telemetry was maintained throughout this period. A 46 m radio astronomy station operated by Stanford University was configured to attempt detection of the UHF-band "pings" through several different means. Spacecraft telemetry indicated nominal operation of the transceiver during this period; however, power and temperature telemetry from components located near the UHF antenna displayed an unpredicted pattern of quasi-cyclic noise spikes due to the UHF radio operation. After the transceiver was powered off all real- time telemetry returned to nominal values. The Stanford antenna was unable to detect the "ping" wavetrain in real time (the probability of doing so was not considered to be high for the detection methods attempted and due to the line of sight blockage of the spacecraft's UHF antenna in the cruise configuration). The flight team is currently evaluating telemetry from this test to better understand the interactions observed. Mars Polar Lander The Mars Polar Lander spacecraft continues to perform well in early cruise. 26 February 1999 Mars Climate Orbiter Mars Climate Orbiter continues in quiet cruise with nothing significant to report. The spacecraft health is excellent. The flight team is now preparing the command sequence for the orbiter's second course correction, TCM-2, scheduled to take place early on the morning of March 4th. Mars Global Surveyor On Wednesday, February 24th, Mars Global Surveyor performed a test of the nadir panel down orientation (pointing the instruments toward the planet) - the orientation required for mapping. During the initial portion of the test, an interaction between the 0.17 Hz natural frequency of the damaged -Y solar panel yoke structure and the attitude control system was observed. Because of the resultant increased activity of the X and Z axis reaction wheels, the rest of the test sequence was canceled. Filter parameters in the attitude control system were modified to notch-out the frequency of concern, and the test was rerun on Friday, February 26th. The results were very favorable. Turn-on of the remaining science instruments (Mars Orbiter Laser Altimeter, Mars Orbiter Camera, and the Thermal Emissions Spectrometer) has been delayed from February 26th to February 28th. A week of focus and calibration of the Mars Orbiter Camera will follow. Mars Polar Lander Mars Polar Lander continues in quiet cruise. The spacecraft health is excellent. On Friday, February 26th, the descent engine valves were opened and the propellant lines were vented to space. This event is timed such that the navigation team has approximately two weeks to observe any resulting effect on the flight path prior to the TCM-2, scheduled for March 15th. ------------------------------------------------------------------ MARS GLOBAL SURVEYOR STATUS REPORT JPL release 22 February 1999 Last Orbit Covered by this Report = 1484 Total Gravity Calibration orbits accomplished = 200 Transfer to Mapping Orbit completed successfully on Orbit 1473 (2/19/99) DV = 22.0 m/sec, Burn Duration = 26.0 sec Pre-TMO Orbital Elements Orbit 1473 (2/19/99): Periapsis Altitude = 414.0 km Periapsis Latitude = 70.8 deg South Orbit Period = 1 hr 58 mins 30 secs Apoapsis Altitude = 419.5 km Inclination = 92.948 km Arg of Per = 214.9 deg Local Mean Solar Time (LMST) at Descending Node = 2:03 AM Post-Burn Orbital Elements Orbit 1474 (2/19/99): Periapsis Altitude = 367.8 km Periapsis Latitude = 86.8 deg South Orbit Period = 1 hr 57 mins 00 secs Apoapsis Altitude = 438.5 km Inclination = 92.910 deg Arg of Periapsis = 268.8 deg Local Mean Solar Time (LMST) at Descending Node = 2:03 AM Recent Events Sequence P1474 is currently controlling the gravity calibration activities. TMO executed perfectly on orbit 1473 to achieve the preliminary "lock" on the MGS "frozen" mapping orbit. The orbit is nearly sun-synchronous--a slight drift in the Local Mean Solar Time (LMST) remains (~1 minute in 42 days). Additional orbit trim maneuvers (OTM's) will be performed as necessary to correct the small dispersions remaining in the achieved orbital elements. However, OTM-1 scheduled for 2/26 has been canceled due to the excellent accuracy of the TMO burn. Further use of the main engine in the mission is not anticipated. The MGS spacecraft has its fully budgeted monopropellant fuel allocations for its frozen orbit trim maneuver, mapping, planetary quarantine, and relay mission phases. In addition, the spacecraft has an unallocated monopropellant fuel reserve of nearly 46 m/s. Approximately 5 kg of oxidizer (NTO) will go unused. All subsystems report excellent health and performance during gravity call operations. Attitude control has been outstanding, with perfect star processing performance. The S/C temperatures continue within limitations. The power subsystem continues strong performance maintaining a current energy balance of 80 W-hrs. This represents about 10% margin of the power subsystem capacity. Autonomous eclipse management (AEM) used to initiate the eclipse ingress and egress events has been working flawlessly. The timing difference between the Navigation predictions and the spacecraft day/night detections has been on the order of 10 seconds for ingress and 40 seconds for egress. The DSN stations have had no trouble locking telemetry with these timing errors. Further correlation is on-going. The telecommunications subsystem continues solid performance. After fixing the on-board eclipse egress script for an 85 kbps playback problem, all playbacks have been proceeding smoothly. On Tuesday 2/16, telemetry unexpectedly showed Solid State Recorder (SSR) 2A powered on but drawing no current. As a point of note, SSR2A had been commanded along with SSRs 1B and 2B to low power mode for the final week of aerobraking, the first time in the mission this mode has been utilized. Commands were immediately prepared and uplinked to power cycle SSR2A, which resulted in a successful power up. Currently SSR2A appears to be functioning properly. SEAKR, the SSR manufacturer, has been notified of the situation and is looking into the matter. In the meantime, command products are in preparation to perform a functional checkout of the recorder. Upcoming Events Nadir Pointing Checkout on February 24 Instrument Power-On February 27 MOC Calibrations from March 1 to 8 Fixed HGA (Contingency Science) March 9 to March 28 HGA Deployment on March 29,1999 Spacecraft Commanding There were 50 command files radiated to the S/C during this period. The total files radiated since launch is now 3318. These commands were sent in support of the following activities: Nominal Gravity Calibration sequences (P1370, P1455, P1474) TMO Maneuver (A1473) TMO AEM script fix for 85 k Playbacks New Alternate Mission Mode EDF and SCP telemetry maps Battery VT curves to VT3S ABX Telemetry Playbacks Full SCP MROs Command loss timer resets Nominal star catalog and ephemeris file updates Unload Buffer MRO SSR 2A anomaly commands ------------------------------------------------------------------ MARS GLOBAL SURVEYOR AEROBRAKING PHASE IMAGE SET AVAILABLE JPL release 27 February 1999 The USGS Flagstaff node of the Planetary Data System in conjunction with Malin Space Science Systems is making the MGS aerobraking phase image set available to scientists and the general pubic. This is one of the primary repositories of publicly released MGS images. Additional image enhancements will be added to the system as they become available. The MOC images are available courtesy of the Flagstaff office of the U.S. Geological Survey. http://ida.wr.usgs.gov In the event that the USGS site receives more than the anticipated traffic we will mirror the content to the Jet Propulsion Laboratory. http://mars.jpl.nasa.gov/mgs/status/usgs-rel.html ------------------------------------------------------------------ LIFE ON THE EDGE UPDATE By Tony Phillips 26 February 1999 Many of you have asked for a brief update on the Life on the Edge project. At present, our container of microorganisms is exposed to harsh winter conditions at 13,500 ft altitude near the summit of the White Mountains in California. The dog sled team has made several forays into the mountains to move the microbe vessel closer and closer to the top and to sample snow in the vicinity of the microbe container. The snow samples will be used in laboratory procedures to test for native microscopic life forms. An update with additional information will be posted to our web site (http://science.nasa.gov) next week. ------------------------------------------------------------------ NASA/NCI BIOSIGNATURES WORKSHOP NASA release 26 February 1999 This is to announce a workshop on new sensors and detection technologies for molecular bio-signatures. This workshop is cosponsored by NASA's Office of Life and Microgravity Sciences and Applications and National Cancer Institute. It will take place June 2-4, 1999 in Pasadena, California. The workshop will explore a common technology base that will further the goals for both sponsoring institutions. Early cancer detection and treatment is the NCI objective while NASA is looking for advanced technologies for its Astrobiology as well as in-situ detection of life in any form elsewhere than on planet Earth programs. We solicit your participation in the workshop and hope that you will consider submitting an abstract and passing this flyer around your institution. For further information, please visit the workshop site at: http://cism.jpl.nasa.gov/events/nasa-nci.html ------------------------------------------------------------------ End Marsbugs Vol. 6, No. 5