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"930414.DFC" (36974 bytes) was created on 04-14-93 14-Apr-93 Daily File Collection These files were added or updated between 13-Apr-93 at 21:00:00 {Central} and 14-Apr-93 at 21:00:27. =--=--=START=--=--= NASA Spacelink File Name:930414.REL 4/14/93: OZONE DESTROYING CHLORINE EXISTED LONGER IN 92-93 WINTER Paula Cleggett-Haleim Headquarters, Washington, D.C. April 14, 1993 James H. Wilson Jet Propulsion Laboratory, Pasadena, Calif. RELEASE: 93-068 Ozone-destroying forms of chlorine existed for much longer in the Arctic stratosphere this winter than last, say scientists. Northern Hemisphere ozone abundance also was observed to be some 10 percent below that measured during the same period last year, with some regions 20 percent lower. Using NASA's Upper Atmosphere Research Satellite (UARS), Dr. Joe Waters and his colleagues at the Jet Propulsion Laboratory (JPL), Pasadena, Calif., and Edinburgh University, Scotland, have collected daily maps of ozone and other gases and of temperature in different layers of the stratosphere. One of their most critical measurements is of chlorine monoxide, a form of chlorine that destroys ozone. They reported the results in the international scientific journal Nature. "Ozone concentrations in the Arctic in a layer about 12 miles (20 kilometers) high, where most chlorine monoxide was located, decreased by 0.7 percent per day from mid-February through early March 1993," Waters said. Ozone levels normally increase in this area at this time of the year, he added. Chlorine already in the stratosphere, from chlorofluorocarbons, is converted to ozone-destroying forms by chemistry occurring on clouds which form at low temperature. Last year, the scientists measured large abundances of chlorine monoxide in the Arctic, but the concentrations decreased after the stratosphere warmed in late January. This winter, the stratosphere remained cold through February, and chlorine monoxide remained abundant through early March. About as much chlorine monoxide was seen in the northern polar regions in February 1993 as was measured at the South Pole before the 1992 Antarctic ozone hole formed. "We do not see a well-defined area of ozone loss that could be described as an Arctic ozone hole," Waters said, "but the smaller abundances of ozone seen throughout the Northern Hemisphere this winter raise the question of whether the chlorine destruction of ozone has been spread over a wider area." Record low values of ozone also have been reported recently by the World Meteorological Organization and Environment Canada. The microwave limb sounder aboard UARS was developed and is operated by JPL, led by Waters and sponsored by NASA's Office of Mission to Planet Earth. Additional members are from Edinburgh University, Heriot-Watt University and the Rutherford-Appleton Laboratory in the United Kingdom. UARS, launched Sept. 12, 1991, aboard Space Shuttle Discovery, is managed by NASA's Goddard Space Flight Center, Greenbelt, Md. Source:NASA Spacelink Modem:205-895-0028 Internet:192.149.89.61 =--=--=-END-=--=--= =--=--=START=--=--= NASA Spacelink File Name:930414.SHU KSC SHUTTLE STATUS 4-14 KENNEDY SPACE CENTER SPACE SHUTTLE STATUS REPORT Wednesday, April 14, 1993 KSC Contact: Bruce Buckingham Mission: STS-56/ATLAS-2/SSBUV Orbital altitude: 184 miles Vehicle: Discovery/OV-103 Inclination: 57 degrees Mission Duration: 8 days/6 hours Crew size: 5 KSC Landing Date/Time: April 16/approximately 7:33 a.m. NOTE: The Shuttle Discovery remains on orbit following launch on April 8 at 1:29 a.m. Landing is scheduled for Friday, April 16, at KSC. There are two opportunities for landing at KSC on Friday, 7:33 a.m. and 9:06 a.m. There is one KSC landing opportunity on Saturday at 7:39 a.m. ----------------------------------------------------------------- Mission: STS-55/SL-D2 Orbital Altitude: 184 miles Vehicle: Columbia/OV-102 Inclination: 28.45 degrees Location: Launch Pad 39-A Crew Size: 7 Mission Duration: 8 days/22 hours KSC Landing: May 3 Target Launch Date: NET April 24 Launch Window: 10:52 a.m. - 12:22 p.m. IN WORK TODAY: * Main engine leak checks * Continue engine check valve leak checks * Orbital maneuvering system heater checks WORK SCHEDULED: * Preparations to enter spacelab to make final service of experiments (Thursday) * External tank purges (Thursday) * Begin aft engine compartment closeouts (Thursday) * Close payload bay doors for flight (Friday) WORK COMPLETED: * Helium signature leak checks * Liquid hydrogen cavity purge * Microwave scanning beam landing system (MSBLS) tests ----------------------------------------------------------------- Mission: STS-57/Spacehab/EURECA-Retrieval Orbital Alt.: 287 miles Vehicle: Endeavour/OV-105 Inclination: 28 degrees Location: Vehicle Assembly Building Crew Size: 6 Mission Duration: 7days/23 hours Target KSC Landing: May 27 Target Launch Date: NET May 19 IN WORK TODAY: * Shuttle interface test * SRB hydraulic closeouts * External tank foaming operations * Pre-rollout inspections WORK SCHEDULED: * Begin main engine installation April 16 * Rollout to pad 39-B targeted for NET April 22 WORK COMPLETED: * Launch countdown simulation * Main engine interface inspections * T-0 umbilical closeouts, leak checks and cavity purge Source:NASA Spacelink Modem:205-895-0028 Internet:192.149.89.61 =--=--=-END-=--=--= =--=--=START=--=--= NASA Spacelink File Name:930414.SKD Daily News/TV Sked 4/14/93 Daily News Wednesday, April 14, 1993 Two Independence Square, Washington, D.C. Audio Service: 202/358-3014 % STS-56 mission update; % Computer program to catalog astronomical sky survey. * * * * * * * * * * * * * * * * Early this morning, Discovery's crew performed the standard pre-landing checkout of the spacecraft and talked with reporters at the Kennedy Space Center. The flight control systems checkout found Discovery's systems in excellent condition and found no problems that would affect the landing. The crew also had the opportunity to speak with interviewers and school children at Channel One television and Chicago's Museum of Science and Industry by WGN television. * * * * * * * * * * * * * * * * NASA's Jet Propulsion Laboratory and the California Institute of Technology (Caltech) announced that they have developed a computer software system to catalog and analyze the estimated half billion sky objects in the second Palomar Observatory sky survey. Caltech astronomer Professor S. Djorgovski said the resulting data set will not be surpassed in quality or scope for the next decade. Caltech astronomer Nick Weir and Dr. Usama Fayyad said the Sky Image Cataloging anad Analysis Tool has a correct sky object classification rate of about 94 percent, which exceeds the performance requirements of 90 percent needed for accurate scientific analysis of the data. Dr. Fayyad further states that the best performance of a commercially available learning algorithm was about 75 percent. * * * * * * * * * * * * * * * * Here's the broadcast schedule for Public Affairs events on NASA TV. Note that all events and times may change without notice and that all times listed are Eastern. Live indicates a program is transmitted live. NASA TV will continue with its 24-hour a day coverage of the STS-56 mission. NASA TV is carried on GE Satcom F2R, transponder 13, C-Band, 72 degrees West Longitude, transponder frequency is 3960 MHz, audio subcarrier is 6.8 MHz, polarization is vertical. Source:NASA Spacelink Modem:205-895-0028 Internet:192.149.89.61 =--=--=-END-=--=--= =--=--=START=--=--= NASA Spacelink File Name:3_6_2.TXT NOTE: This file is too large {28294 bytes} for inclusion in this collection. The first line of the file: SHUTTLE PAYLOAD FLIGHT ASSIGNMENTS Source:NASA Spacelink Modem:205-895-0028 Internet:192.149.89.61 =--=--=-END-=--=--= =--=--=START=--=--= NASA Spacelink File Name:6_15_18.TXT 4/14/93: OZONE DESTROYING CHLORINE EXISTED LONGER IN 92-93 WINTER Paula Cleggett-Haleim Headquarters, Washington, D.C. April 14, 1993 James H. Wilson Jet Propulsion Laboratory, Pasadena, Calif. RELEASE: 93-068 Ozone-destroying forms of chlorine existed for much longer in the Arctic stratosphere this winter than last, say scientists. Northern Hemisphere ozone abundance also was observed to be some 10 percent below that measured during the same period last year, with some regions 20 percent lower. Using NASA's Upper Atmosphere Research Satellite (UARS), Dr. Joe Waters and his colleagues at the Jet Propulsion Laboratory (JPL), Pasadena, Calif., and Edinburgh University, Scotland, have collected daily maps of ozone and other gases and of temperature in different layers of the stratosphere. One of their most critical measurements is of chlorine monoxide, a form of chlorine that destroys ozone. They reported the results in the international scientific journal Nature. "Ozone concentrations in the Arctic in a layer about 12 miles (20 kilometers) high, where most chlorine monoxide was located, decreased by 0.7 percent per day from mid-February through early March 1993," Waters said. Ozone levels normally increase in this area at this time of the year, he added. Chlorine already in the stratosphere, from chlorofluorocarbons, is converted to ozone-destroying forms by chemistry occurring on clouds which form at low temperature. Last year, the scientists measured large abundances of chlorine monoxide in the Arctic, but the concentrations decreased after the stratosphere warmed in late January. This winter, the stratosphere remained cold through February, and chlorine monoxide remained abundant through early March. About as much chlorine monoxide was seen in the northern polar regions in February 1993 as was measured at the South Pole before the 1992 Antarctic ozone hole formed. "We do not see a well-defined area of ozone loss that could be described as an Arctic ozone hole," Waters said, "but the smaller abundances of ozone seen throughout the Northern Hemisphere this winter raise the question of whether the chlorine destruction of ozone has been spread over a wider area." Record low values of ozone also have been reported recently by the World Meteorological Organization and Environment Canada. The microwave limb sounder aboard UARS was developed and is operated by JPL, led by Waters and sponsored by NASA's Office of Mission to Planet Earth. Additional members are from Edinburgh University, Heriot-Watt University and the Rutherford-Appleton Laboratory in the United Kingdom. UARS, launched Sept. 12, 1991, aboard Space Shuttle Discovery, is managed by NASA's Goddard Space Flight Center, Greenbelt, Md. Source:NASA Spacelink Modem:205-895-0028 Internet:192.149.89.61 =--=--=-END-=--=--= =--=--=START=--=--= NASA Spacelink File Name:6_2_18_5.TXT NOTE: This file is too large {28919 bytes} for inclusion in this collection. The first line of the file: - Current Two-Line Element Sets #173 - Source:NASA Spacelink Modem:205-895-0028 Internet:192.149.89.61 =--=--=-END-=--=--= =--=--=START=--=--= NASA Spacelink File Name:6_2_2_44_12_29.TXT ATLAS 2 Public Affairs Status Report #12 6:00 p.m. CDT, April 13, 1993 5/17:31 MET Spacelab Mission Operations Control Marshall Space Flight Center Huntsville, Alabama The ATLAS 2 solar instruments completed four orbits of observations at around 1 p.m. CDT. This was the third of four periods planned during ATLAS 2 when the Shuttle's cargo bay will be pointed to the sun. By accumulating data during multiple observation periods, scientists have more points of comparison to arrive at extremely precise measurements of the sun's total energy output and how it is broken down by wavelength. Multiple solar periods also allow them to study short-term solar variations. All the solar instruments again collected very high quality data. Two University of Colorado students participated in science planning meetings in Huntsville during the last three solar observation periods. The students represented a Colorado Space Grant Consortium project, the Solar Ultraviolet Experiment (SUVE), housed in a Get-Away-Special canister in the Shuttle cargo bay. Although not part of the ATLAS 2 payload, SUVE is making observations concurrently with the ATLAS solar instruments. SUVE's study of extreme ultraviolet solar radiation will complement both ATLAS and SPARTAN measurements. The experiment was designed, managed and built at the University of Colorado in Boulder. The Space Grant Consortium program is funded by NASA to educate students in the science and engineering aspects of exploring and working in space. After the solar period ended, the Shuttle crew maneuvered Discovery's cargo bay to point toward Earth for the mission's fourth period of atmospheric observations. For the first three orbits, the Shuttle has traveled with its nose into the flight path as it did during the previous atmospheric viewing periods, rather than tail-first as had been planned. This change allowed an increased data flow to the ground, making it possible to dump three additional Atmospheric Trace Molecule Spectroscopy (ATMOS) observations from the Spacelab High Data Rate Recorder. ATMOS Principal Investigator Dr. Mike Gunson gave high praise to the data management team at Spacelab Mission Operations Control for their efforts to retrieve a maximum amount of high-rate ATMOS data. "They explored every possible way to cram every available recorder with ATMOS observations," said Gunson. The data team has been scheduling dumps of ATMOS data from the Spacelab recorder as Tracking and Data Relay Satellite coverage allows. Because the data is coming down at a rate sixteen times slower than that at which it was acquired, the scheduling is a fairly complicated process. However, the team expects to get the majority of ATMOS observations dumped from the Spacelab recorder by the end of the mission. ATMOS has reduced the length of observations from four minutes to two minutes to allow more sunrises and sunsets to be recorded. The shortened observations will only reach as high as the the top of the mesosphere. However, because the stratosphere (the atmospheric layer beneath the mesosphere) is of primary interest to ATMOS, this change results in relatively little scientific loss. The ATMOS experiment team also was pleased to find their onboard recorder is not full, as they suspected at the end of yesterday's atmospheric period. Observations will continue to be captured on the onboard recorder until it has indeed reached capacity. This morning, Principal Investigator Gunson estimated there may be room for 10 to 15 more observations on the recorder. ATMOS ground monitors indicate when the recorder is on or off, but not how much of the tape has been used. On the fourth atmospheric orbit, beginning at around 6 p.m., the Shuttle will turn with its tail to the flight path. This reorientation will allow the Millimeter-Wave Atmospheric Sounder (MAS), positioned on the left side of the cargo bay, to take readings of the Northern Hemisphere polar region as the stratosphere makes the critical transition from winter. The MAS team gave up three of 23 scheduled North-viewing orbits to allow the extra ATMOS downlinks, in what Mission Scientist Dr. Tim Miller termed an example of "scientific altruism." MAS looked toward the South during the three earlier atmospheric sessions. The instrument only pointed toward the South for a small portion of its ATLAS 1 observations. The MAS team has decided to forego some calibrations planned for the remainder of the flight, since a calibration mirror proved difficult to move out of their antenna's field of view after an early-morning calibration. The change will complicate post-flight calibration somewhat, but it is not expected to have a significant impact on the accuracy of their data. Science teams and payload controllers at Marshall are considering the best ways to use any additional experiment time, should it become available due to a weather-related landing delay. The current, 26-orbit atmospheric period will continue until early Thursday morning. Source:NASA Spacelink Modem:205-895-0028 Internet:192.149.89.61 =--=--=-END-=--=--= =--=--=START=--=--= NASA Spacelink File Name:6_2_2_44_12_30.TXT STS-56 Status Report #17 MISSION CONTROL CENTER Wednesday, April 14, 1993, 5:30 a.m. CDT Discovery's crew performed a standard pre-landing checkout of their spacecraft and then talked with reporters at the Kennedy Space Center during an early morning press conference. Commander Ken Cameron and Pilot Steve Oswald went through a normal hour and a half checkout of the equipment Discovery will use for its return home to the Kennedy Space Center on Friday. The flight control systems checkout found Discovery's systems in excellent condition with no problems that would affect the return to Earth. At about 4:09 a.m. CDT, Discovery's crew talked with members of the press at Kennedy. During the 20-minute session, crew members discussed their views of Earth, their sighting and contact with the Russian Mir Space Station, their impressions of increased cooperation with Russia in space, and their atmospheric work and other experiments aboard Discovery. Earlier in the morning, Cameron and the rest of the crew received a television transmisssion of Mission Control by a ham radio experiment on the shuttle. It was the second such transmission the crew reported having seen. As it took place, flight controllers watched the crew's reaction by standard television sent from the spacecraft. Discovery's crew will speak with interviewers and school children at Channel One television at about 10:14 a.m. central today and with Chicago's Museum of Science and Industry by WGN television at 11:54 a.m. central. Discovery remains in a 160 by 156 nautical mile orbit, circling Earth once each 90 minutes. ******* Source:NASA Spacelink Modem:205-895-0028 Internet:192.149.89.61 =--=--=-END-=--=--= =--=--=START=--=--= NASA Spacelink File Name:6_2_2_44_12_31.TXT STS-56 MCC Status Report #18 MISSION CONTROL CENTER STS-56 Status Report #18 Wednesday, April 14, 1993, 2 p.m. CDT Science data gathering in support of the ATLAS instruments in Discovery's payload bay continued throughout the day, while crew members took part in several in-flight special events. Several successful ham radio contacts were made today with the Franklin Institute in Philadelphia, Pennsylvania, and Wilson Junior High School in El Centro, California. Additional contacts are planned throughout tonight. One container of the rodent experiment automatically switched from night to day at one point. Commander Ken Cameron manually activated the light. The experiment now is operating normally. Operations with the HERCULES precise targeting camera equipment also continued throughout the day in parallel with ATLAS observations. Mission Specialist Ellen Ochoa took time out to discuss the flight with school children in California and Mississippi during an interview with Channel 1, a daily newscast for junior and senior high school students. In a second interview, Ochoa talked with students at Chicago's Museum of Science and Technology. Discovery currently is circling the Earth every 90 minutes at an altitude of 160 nautical miles. * * * Source:NASA Spacelink Modem:205-895-0028 Internet:192.149.89.61 =--=--=-END-=--=--= =--=--=START=--=--= NASA Spacelink File Name:6_2_2_44_12_32.TXT ATLAS 2 STATUS #13 ATLAS 2 Public Affairs Status Report #13 6:00 a.m. CDT, April 14, 1993 6/05:31 MET Spacelab Mission Operations Control Marshall Space Flight Center Huntsville, Alabama During its sixth night in orbit, the second Atmospheric Laboratory for Applications and Science (ATLAS 2) payload gathered data about the relationship between the Earth and sun. Scientists from the U.S., Belgium, Germany, France, The Netherlands and Switzerland are participating in this Spacelab mission, an integral part of NASA's Mission to Planet Earth. While atmospheric instruments were taking advantage of their fourth observation period, Mission Specialist Michael Foale performed an in-flight maintenance procedure that temporarily corrected a problem with the on-board Global Positioning System (GPS). The GPS, designed to indicate an object's position in space, is being flown and evaluated for the first time on a Spacelab mission. After landing, scientists will look at the information from GPS to help confirm the orbiter's position during their data-collection periods. The Atmospheric Trace Molecule Spectroscopy (ATMOS) instrument continued to observe orbital sunsets and sunrises to identify and measure molecules and their vertical distribution in the atmosphere, and the device acquired good spectral data on key types of these molecules (i.e. chlorine nitrate) that it was intended to measure as part of its science objectives. During the night, this instrument also viewed the sun with no atmosphere. This procedure provides a solar reference for calibrating the ATMOS equipment. Once the ATMOS dedicated recorder becomes full, the observation periods will be shortened from four minutes to two minutes, allowing the instrument to view the stratosphere (the primary target for this investigation), the mesosphere, but not the thermosphere. Once the recorder is filled to capacity, the data collected during these two-minute observations will later be selectively captured on the Spacelab High Data Rate Recorder. The ATMOS science team, working from the Spacelab Mission Operations Control center in Huntsville, Ala., closely monitored the remaining storage capacity of the Spacelab recorder to ensure the maximum number of atmospheric measurements would be available for analysis after landing. Overnight, the Millimeter-wave Atmospheric Sounder (MAS), a joint investigation for Germany, Switzerland and the United States, continued to operate with its Hot Target calibration mirror locked in the "out" position. This allowed data acquisition but will make post-flight analysis somewhat more complicated. However, data quality appears to be as good as that obtained in nominal mode, and the device measured the amounts of chlorine monoxide in the atmosphere during the daylight portions of the orbits. During the dark, or shadowed, portion of the orbits, this instrument scanned the atmosphere, measuring molecules that were present at different altitudes, using what is known as a stepped-pointing mode. Two other instruments of the ATLAS 2 payload operated overnight, helping scientists to measure the amount of solar radiation that bounces back from the top of the Earth's atmosphere. The Shuttle Solar Backscatter Ultraviolet (SSBUV) experiment measured ultraviolet radiation as part of an investigation into the amount of ozone present in our atmosphere. During the fourth run of an experimental SSBUV procedure, sulfur dioxide readings were made as the orbiter passed over industrialized areas of Japan. SSBUV Mission Manager, Mr. Don Williams, reported that the amount of data collected so far for ATLAS 2 has surpassed the volume of data that was collected during ATLAS 1 in 1992. The Solar Spectrum Measurement (SOLSPEC) instrument, which measures solar radiation in the ultraviolet, visible and near-infrared wavelengths in conjunction with its sister instrument aboard the European Retrievable Carrier (EURECA) satellite, viewed the Earth during this atmospheric observation period. Although primarily a solar instrument, SOLSPEC took advantage of the Earth-viewing position of the orbiter to record ultraviolet and visible light as it scattered back from the atmosphere. This data will be combined with information from SOLSPEC's solar observations to determine concentrations of trace gases in the atmosphere. The next 12 hour period will be dedicated to continued atmospheric observations by the ATMOS, MAS, SSBUV and SOLSPEC instruments. Source:NASA Spacelink Modem:205-895-0028 Internet:192.149.89.61 =--=--=-END-=--=--= =--=--=START=--=--= NASA Spacelink File Name:6_2_2_44_7.TXT STS-56 Keplerian Elements/State Vector STS-56 element set GSFC-021 (orbit 97) STS-56 1 22621U 93 23 A 93104.25176571 0.00045467 00000-0 13024-3 0 216 2 22621 57.0049 151.0369 0003961 279.5591 80.5039 15.92828848 978 Satellite: STS-56 Catalog number: 22621 Epoch time: 93104.25176571 (14 APR 93 06:02:32.56 UTC) Element set: GSFC-021 Inclination: 57.0049 deg RA of node: 151.0369 deg Space Shuttle Flight STS-56 Eccentricity: 0.0003961 Keplerian Elements Arg of perigee: 279.5591 deg Mean anomaly: 80.5039 deg Mean motion: 15.92828848 rev/day Semi-major Axis: 6672.5032 Km Decay rate: 0.45E-03 rev/day*2 Apogee Alt: 296.76 Km Epoch rev: 97 Perigee Alt: 291.47 Km NOTE - This element set is based on NORAD element set # 021. The spacecraft has been propagated to the next ascending node, and the orbit number has been adjusted to bring it into agreement with the NASA numbering convention. R.A. Parise, Goddard Space Flight Center G.L.CARMAN STS-56 Flight Day 6 Vector STS-56 FLIGHT DAY 6 STATE VECTOR (ACTUAL) ON ORBIT OPERATIONS (Posted 04/13/93 by Bruce Williamson) The following vector for the flight of STS-56 is provided by NASA Johnson Space Center Flight Design and Dynamics Division for use in ground track plotting programs. The vector is valid for flight day six. The vector represents the trajectory of Discovery after completion of the SPARTAN rendezvous. Questions regarding these postings may be addressed to Don Pearson, Mail Code DM4, L. B. J. Space Center, Houston, Texas 77058, Telephone (713) 483-8052. Lift off Time : 1993/098/05:28:59.950 Lift off Date : 04/08/93 Vector Time (GMT) : 103/16:58:59.950 Vector Time (MET) : 005/11:30:00.000 Orbit Count : 88 Weight : 221270.0 LBS Drag Coefficient : 2.00 Drag Area : 5000.0 SQ FT M50 Elements Keplerian Elements ----------------------- -------------------------- X = 4769886.8 FT A = 3600.7239 NM Y = -14104573.4 FT E = 0.0006550 Z = 16034817.8 FT I (M50) = 57.10113 DEG Xdot = 22767.280310 FT/S Wp (M50) = 16.17316 DEG Ydot = -4129.428495 FT/S RAAN (M50) = 152.84509 DEG Zdot = -10382.843003 FT/S / N (True) = 103.04561 DEG Anomalies \ M (Mean) = 102.97248 DEG Ha = 160.39550 NM Hp = 156.61930 NM Mean of 1950 (M50) : Inertial, right-handed Cartesian system whose Coordinate System origin is the center of the earth. The epoch is the beginning of the Besselian year 1950. X axis: Mean vernal equinox of epoch Z axis: Earth's mean rotational axis of epoch Y axis: Completes right-hand system A: Semi-major axis E: Eccentricity N: True anomaly I: Inclination M: Mean anomaly Wp: Argument of perigee Ha: Height of apogee RAAN: Right ascension of ascending node Hp: Height of perigee Source:NASA Spacelink Modem:205-895-0028 Internet:192.149.89.61 =--=--=-END-=--=--= =--=--=START=--=--= NASA Spacelink File Name:6_8_4_9_33.TXT Mars Observer Status 4-14-93 PUBLIC INFORMATION OFFICE JET PROPULSION LABORATORY CALIFORNIA INSTITUTE OF TECHNOLOGY NATIONAL AERONAUTICS AND SPACE ADMINISTRATION PASADENA, CALIF. 91109. MARS OBSERVER MISSION STATUS April 14, 1993 All spacecraft subsystems are performing well as Mars Observer heads for a rendezvous with the Red Planet on Aug. 24, 1993. The spacecraft experienced a slight attitude change on Friday, April 9, when an internal software test failed and erroneously indicated that inertial reference had been lost. When this happened, on-board fault protection initiated a "contingency mode," which automatically switched spacecraft communications from the high-gain to the low-gain antenna. Data rates and power consumption were reduced, and the solar arrays were repositioned to a more favorable orientation toward the sun. The incident has occurred before and ground controllers understand it. No hardware problems are involved and the spacecraft performed flawlessly in switching to the contingency mode. A command sequence to modify on-board software will be uplinked in late May. Meanwhile, the spacecraft was returned to normal cruise configuration late Tuesday, April 13. A magnetometer calibration sequence that would have occurred during the recovery period was postponed until May. The camera team began a series of narrow-angle and wide- angle imaging tests on Tuesday afternoon, and photographed Jupiter while it was in the camera's field of view Tuesday night. The camera tests were executed by non-stored sequence commands that were closely coordinated by instrument, spacecraft and ground operations teams. The gravitational wave experiment using Mars Observer and two other interplanetary spacecraft -- Galileo and Ulysses -- also concluded this week, on Monday, April 12, at about 1:20 a.m. Pacific Daylight Time. The radio science team will spend a minimum of six months analyzing the data. Results may be forthcoming by fall or winter 1993. Today the Mars Observer spacecraft is about 25 million kilometers (15 million miles) from Mars and 178 million kilometers (111 million miles) from Earth. The spacecraft is traveling at a velocity of about 8,200 kilometers per hour (5,000 miles per hour) with respect to Mars. Source:NASA Spacelink Modem:205-895-0028 Internet:192.149.89.61 =--=--=-END-=--=--= =--=--=START=--=--= NASA Spacelink File Name:9_10_8.TXT M I C R O G R A V I T Y D E M O N S T R A T O R SUBJECT: Space Flight TOPIC: Free fall DESCRIPTION: A water stream coming out of a hole in a styrofoam cup stops when the cup is dropped. MATERIALS: Styrofoam coffee cup Pencil or other pointed object Water Bucket or other water catch basin PROCEDURES: 1. Punch a small hole in the side of a styrofoam cup near its bottom. 2. Hold your thumb over the hole as you fill the cup with water. Ask students what will happen if you remove your thumb. 3. Remove your thumb and let the water stream out into the catch basin on the floor. ____________ [ ] \ / \ / \____o_/ | : | 4. Again seal the hole with your thumb and refill the the cup. Ask students if the water will fall out of the hole if you drop the cup as you remove your thumb. 5. Drop the filled cup into the catch basin. | | | | | | | | | | | | | ___________ [ ] \ / \ / \___o_/ DISCUSSION: The microgravity that astronauts experience inside the Space Shuttle is really NOT zero-G at all. Zero-G implies that gravitional pull in space is zero. This is not the case. Astronauts "float" in space because they are in a state of free fall produced by their orbital motions around the Earth. Astronauts and their space- craft are falling together. The condition is better described as "freefall" because a bathroom scale inside the Shuttle would not record any weight for an astronaut standing on it. The scale would be falling too. The falling styrofoam cup demonstrates microgravity (or freefall) for a brief period of time. When station- ary, water freely pours out of the cup. If the cup falls too, the water remains inside the cup for the entire fall. Even though the water remains inside, it is still attracted to the Earth by gravity and it ends up in the same place that the water from the first experiment did. --- Contributed by Dale Bremmer, NASA/AESP Source:NASA Spacelink Modem:205-895-0028 Internet:192.149.89.61 =--=--=-END-=--=--= =--=--=START=--=--= NASA Spacelink File Name:9_3_14.TXT M I C R O G R A V I T Y D E M O N S T R A T O R SUBJECT: Space Flight TOPIC: Free fall DESCRIPTION: A water stream coming out of a hole in a styrofoam cup stops when the cup is dropped. MATERIALS: Styrofoam coffee cup Pencil or other pointed object Water Bucket or other water catch basin PROCEDURES: 1. Punch a small hole in the side of a styrofoam cup near its bottom. 2. Hold your thumb over the hole as you fill the cup with water. Ask students what will happen if you remove your thumb. 3. Remove your thumb and let the water stream out into the catch basin on the floor. ____________ [ ] \ / \ / \____o_/ | : | 4. Again seal the hole with your thumb and refill the the cup. Ask students if the water will fall out of the hole if you drop the cup as you remove your thumb. 5. Drop the filled cup into the catch basin. | | | | | | | | | | | | | ___________ [ ] \ / \ / \___o_/ DISCUSSION: Microgravity that astronauts experience inside the Space Shuttle is really NOT zero-G at all. Zero-G implies that gravitional pull in space is zero. This is not the case. Astronauts "float" in space because they are in a state of free fall produced by their orbital motions around the Earth. Astronauts and their space- craft are falling together. The condition is better described as "freefall" because a bathroom scale inside the Shuttle would not record any weight for an astronaut standing on it. The scale would be falling too. The falling styrofoam cup demonstrates microgravity (or freefall) for a brief period of time. When station- ary, water freely pours out of the cup. If the cup falls too, the water remains inside the cup for the entire fall. Even though the water remains inside, it is still attracted to the Earth by gravity and it ends up in the same place that the water from the first experiment did. --- Contributed by Dale Bremmer, NASA/AESP Source:NASA Spacelink Modem:205-895-0028 Internet:192.149.89.61 =--=--=-END-=--=--= =--=END OF COLLECTION---COLLECTED 14 FILES---COMPLETED 21:20:42=--=