Date: Sat, 12 Dec 92 05:24:15 From: Space Digest maintainer Reply-To: Space-request@isu.isunet.edu Subject: Space Digest V15 #538 To: Space Digest Readers Precedence: bulk Space Digest Sat, 12 Dec 92 Volume 15 : Issue 538 Today's Topics: absolutely, positively overnight (2 msgs) Casinissini Udergoed Intense Design Review Galileo Update - 12/11/92 Space Tourism Welcome to the Space Digest!! Please send your messages to "space@isu.isunet.edu", and (un)subscription requests of the form "Subscribe Space " to one of these addresses: listserv@uga (BITNET), rice::boyle (SPAN/NSInet), utadnx::utspan::rice::boyle (THENET), or space-REQUEST@isu.isunet.edu (Internet). ---------------------------------------------------------------------- Date: Fri, 11 Dec 1992 16:40:45 GMT From: "forrest.e.gehrke" Subject: absolutely, positively overnight Newsgroups: sci.space In article henry@zoo.toronto.edu (Henry Spencer) writes: > >It probably will be subject to missile-proliferation rules, at least at >the start. If spaceships start becoming common, then limited missile >defences are probably going to become common too. (They have to anyway, >because building a V-2 equivalent is no longer that difficult.) >-- You mean (Gasp!) Senator Nunn will have to give up and agree to ending the Anti-missile Treaty? Forrest Gehrke feg@dodger.att.com ------------------------------ Date: 11 Dec 92 22:07:11 GMT From: Henry Spencer Subject: absolutely, positively overnight Newsgroups: sci.space In article <1992Dec11.172437.24552@ke4zv.uucp> gary@ke4zv.UUCP (Gary Coffman) writes: >>... The Saudi >>royal family would surely buy one. And then there's Air Force One... > >Take a look at Air Force One, or Two. A 747 and a 707. The Air Force >is very conservative in the choice of aircraft on which to fly the >President. The Saudi royals are even more conservative... Give DC 20 >years of routine passenger carrying flight experience... They adopted the 707 much more quickly than that. The long delay for the transition to the 747 was because it was a lot more expensive and the 707s were working well, not because they were nervous about the 747 being new. I don't seriously expect that a DC-1 would ever become Air Force One, actually. Not because it's dangerous, but because it's too *small*, and because servicing facilities for it won't be nearly as common as those for 747s for a long time. But I rather suspect it would be rather less than twenty years before the president rides in one. He *is* the boss, after all... -- "God willing... we shall return." | Henry Spencer @ U of Toronto Zoology -Gene Cernan, the Moon, Dec 1972 | henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: 12 Dec 92 05:58:31 GMT From: Ryan Korniloff Subject: Casinissini Udergoed Intense Design Review Newsgroups: sci.space Regarding the Titan probe - will it have a camra to take images of the landscape? I am aware of how dim the sun is at tha distance compounded with the thickness of Titan's atmosphere. But these shouldn't require mayjor technical feats.. -- Ryan Korniloff -- rkornilo@nyx.cs.du.edu ------------------------------ Date: 12 Dec 92 06:34:51 GMT From: Ron Baalke Subject: Galileo Update - 12/11/92 Newsgroups: sci.space,sci.astro.alt.sci.planetary Forwarded from Neal Ausman, Galileo Mission Director GALILEO MISSION DIRECTOR STATUS REPORT POST-LAUNCH December 4 - 10, 1992 SPACECRAFT 1. On December 4, real-time commands were sent to change the telemetry rate from 115.2 kbps to 28.8 kbps so that DSS-12 (Goldstone 34 meter antenna) could process downlink telemetry. This change was necessary when ground station problems at DSS-14 (Goldstone 70 meter antenna) caused the Project to request tracking support at DSS-12. The spacecraft telemetry rate under stored sequence control was switched back to 115.2 kbps after DSS-12 tracking support ended. Upon completion of commanding, the CDS (Command Data Subsystem) command lock counter had increased by 4 which was 2 more than expected. No unplanned commands were received/processed by the spacecraft. Analysis of this incident is in progress. 2. On December 4, Part 1 of the EE-11 Earth encounter sequence memory load was uplinked to the spacecraft without incident. Part 2 of the EE-11 Earth encounter sequence memory load was uplinked on December 7. This sequence covers spacecraft activities from December 7, 1992 to December 28, 1992 and includes the Earth closest approach on December 8, 1992. The December 7 EE-11 uplink was delayed for approximately 45 minutes while the ground station transmitter configuration was changed from 18kw with 4db command modulation suppression to 5.5kw with 0.5db command modulation suppression to eliminate command feedthru degradation of downlink telemetry. 3. During this reporting period, numerous science instrument calibration/characterization activities were performed to take advantage of the high telemetry data rates while close to the Earth. Activities included Magnetometer (MAG) scan platform interference test, Solid State Imaging (SSI) boomscatter test, and a MAG calibration coil. All calibration/characterization activities were performed nominally and data analysis is in progress. 4. On December 5, real-time commands were sent to update the gyro drift parameters using spacecraft gyro data collected on November 29. This update was performed to meet the scan platform pointing requirements in support of Earth 2 science data collection when the star scanner shutter was closed. 5. On December 5, real-time commands were sent to disable the AACS (Attitude and Articulation Control Subsystem) sun-dependent algorithms and enable the AACS bright body fault protection in preparation for the Earth 2 flyby. The commands executed nominally on the spacecraft prior to the start of the EE-11 Earth encounter sequence. 6. On December 5 and 6, NO-OP commands were sent to reset the command loss timer to 72 hours, its planned value during this mission phase. 7. On December 8, Earth closest approach occurred at 7:09:25 AM PST at an altitude of 303.1 km. The Earth Gravity Assist (EGA) was performed flawlessly. During the Earth closest approach time period, the Galileo spacecraft took observations of the magnetosphere, Moon and Earth system. 8. On December 8, approximately three hours after closest approach, real-time commands were sent to enable the AACS attitude control sun dependent algorithms to their nominal post fly-by state. Also, the command loss timer was reset to 11 days in accordance with the EE-11 sequence strategy. 9. On December 8, real-time commands were sent to update the attitude control bright body vector in the EE-11 Earth encounter sequence to permit star set acquisition for the December 10 stored-sequence SITURN. 10. On December 8, after approximately 8 hours after closest approach, real-time commands were sent at PI (Principal Investigator's) request to turn off the Energetic Particle Detector (EPD) LEMMS-A detector bias. 11. On December 9, the Galileo Optical Communications Experiment from an Earth-based Xmitter (GOPEX) experiment began. This experiment consists of pulsing a laser at the Galileo spacecraft from the Table Mountain Observatory (TMO) and the Starfire Optical Range (SOR). The Solid State Imaging (SSI) camera is shuttered while slewing across the Earth resulting in a series of illuminated pixels in the image. The experiment is continuing at the writing of this report. Preliminary analysis of the data is in progress. 12. On December 10, the spacecraft executed an 11-degree SITURN. The main purpose of the SITURN was to maintain the spacecraft within plus or minus 10 degrees of the sun at the current solar distance. 13. The AC/DC bus imbalance measurements exhibited some change. The AC measurement has ranged from 16DN to 17DN and now reads 17DN (3.9 volts). The DC measurement has ranged from 115DN (13.4 volts) to 148DN (17.4 volts) and now reads 132DN (15.5 volts). These measurement variations are consistent with the model developed by the AC/DC special anomaly team. 14. The Spacecraft status as of December 10, 1992, is as follows: a) System Power Margin - 59 watts b) Spin Configuration - Dual-Spin c) Spin Rate/Sensor - 3.15rpm/Star Scanner d) Spacecraft Attitude is approximately 4 degree off-sun (leading) and 95 degrees off-earth (leading) e) Downlink telemetry rate/antenna-67.2kbps (coded)/LGA-1 f) General Thermal Control - all temperatures within acceptable range g) RPM Tank Pressures - all within acceptable range h) Orbiter Science- all instruments are powered on except the PPR i) Probe/RRH - powered off, temperatures within acceptable range j) CMD Loss Timer Setting - 264 hours Time To Initiation - 215 hours TRAJECTORY As of noon Thursday, December 10, 1992, the Galileo Spacecraft trajectory status was as follows: Distance from Earth 1,583,900 km (.01 AU) Distance from Sun 147,088,200 km (0.98 AU) Heliocentric Speed 140,500 km per hour Distance from Jupiter 857,457,800 km Round Trip Light Time 0 minutes, 12 seconds SPECIAL TOPIC 1. As of December 10, 1992, a total of 8786 real-time commands have been transmitted to Galileo since Launch. Of these, 3753 were initiated in the sequence design process and 5033 initiated in the real-time command process. In the past week, 74 real time commands were transmitted: 72 were initiated in the sequence design process and 2 initiated in the real time command process. Major command activities this week included commands to change the telemetry rate, uplink the EE-11 Earth encounter sequence memory load, update gyro drift parameters, disable sun-dependent algorithms, enable bright body fault protection, reset the command loss timer, enable the sun-dependent algorithms, update the bright body vector, and turn the EPD detector bias off. 2. Intermittent telemetry has been observed since Earth closest approach as a result of a 6db variation in signal levels received at the tracking stations. The causes for these variations is presently unknown, but is likely the result of spacecraft boom/structural interference, high telecom cone angles (>110 degrees) and possibly RF leakage from LGA-2 (Low Gain Antenna #2). After the SITURN on December 10, the cone angle was approximately 95 degrees and the ground received signal variations and data degradations were considerably reduced. Analysis of the trajectory and the stored-sequence planned SITURN indicates that the cone angle will not again reach 100 degrees. A stored-sequence SITURN on December 16, prior to the Earth/Moon conjunction playback, will further reduce the cone angle to less than 85 degrees. At cone angels less than 85 degrees no boom/structural interferences is possible; correspondingly telecommunication performance is expected to further improve. ___ _____ ___ /_ /| /____/ \ /_ /| Ron Baalke | baalke@kelvin.jpl.nasa.gov | | | | __ \ /| | | | Jet Propulsion Lab | ___| | | | |__) |/ | | |__ M/S 525-3684 Telos | The 3 things that children /___| | | | ___/ | |/__ /| Pasadena, CA 91109 | find the most fascinating: |_____|/ |_|/ |_____|/ | space, dinosaurs and ghosts. ------------------------------ Date: 11 Dec 92 21:23:21 GMT From: Josh 'K' Hopkins Subject: Space Tourism Newsgroups: sci.space henry@zoo.toronto.edu (Henry Spencer) writes: [responding to me..] >>That was the subject in mind. I agree on space tourism. Do you have any >>numbers to post though? >I don't know what the numbers were like, but I do know that business was >brisk when Society Expeditions was taking bookings for hoped-for Phoenix >orbital flights at $50k a head. Right. There was an Air & Space article on this a number of years ago. They also carried the original add in their first issue - quite an eyecatcher. As I recall there were something like 350 people who put down $500 deposits on a $52,000 flight. I think they were eventually refunded but I'm pretty sure that they were supposed to be non-refundable. So, if 350 people will pay $52,000 for a vehicle that isn't flying and isn't all that heavily advertised I think we can assume that this price will provide a big enough market for space tourism. The next question is how much higher it can get before the market dries up. Is there any other data out there? What's the maximum that real people pay for really cool Earth-bound trips? Anyone ever priced a trip to Antarctica? -- Josh Hopkins jbh55289@uxa.cso.uiuc.edu Ho^3 !=L ------------------------------ End of Space Digest Volume 15 : Issue 538 ------------------------------