Date: Fri, 22 Jan 93 05:02:05 From: Space Digest maintainer Reply-To: Space-request@isu.isunet.edu Subject: Space Digest V16 #071 To: Space Digest Readers Precedence: bulk Space Digest Fri, 22 Jan 93 Volume 16 : Issue 071 Today's Topics: DC-1 eventual construction question... Defuse Xray Experiment Galileo Update - 01/21/93 Making Orbit 93 - The Delta Clipper Program Russians plan 540 day Mir mission Sabatier reactor? (was Re: Oxygen in Biosphere 2) 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: 21 Jan 93 22:17:26 GMT From: games@max.u.washington.edu Subject: DC-1 eventual construction question... Newsgroups: sci.space Let me start by making 4 assumptions. 1: The DC-X tests in a couple of months will be a success. 2: MCD successfully builds more of the DC-X's as sounding rockets. 3: Funding for DC-Y never materializes. 4: We want the DC-Y and DC-1 to be built. Now, the question is, HOW to we accomplish this goal. Assuming that the big G doesn't kick in money, we are left with convincing MD of the long term commercial viability of further development. I can't personally pony up the money to place an order for one, but I know some people who might be interested in taking the risk. (And, NO, they would not have enough for more than a percentage of the price tag...) The problem is that if MD operates like Boeing, then they need a certain number of guaranteed saled before going into full development. I don't know that if there are say 20 of these things built, that I can take my 1 and make a living with it. (I.E. show a profit on it's operation.) I am sure that somebody somewhere has crunched these numbers, and has a picture of what it would take to operate a DC in a business environment. Are there those among us that would put their money where there hearts are, and invest (heavily) in such a venture? (I know that we can assume the tourism market.) Does MD have commercial carriers in the wings lined up for purchase of these things, that we don't generally know about? What kind of deal would it take for MD to plug on ahead? John. ------------------------------ Date: Thu, 21 Jan 1993 19:43:31 GMT From: Dick Edgar Subject: Defuse Xray Experiment Newsgroups: sci.space In article TCS1%DCC.BITNET@uga.cc.uga.edu (Tom Schruefer) writes: > >>With the successful deploy of TDRS-F, STS-54's other primary payload bean >>operations. During orbital night, the Diffuse X-Ray Spectrometer will tke >>measurements of the x-ray background of the solar system's interstellar >>medium. This information will be used to answer questions about a nearb >>super nova that scientists believe occurred about 300,000 years ago. > > Does anyone know which star they are talking about ??? > This *may* have to do with the Geminga object, recently revealed by Rosat and GRO to be a pulsar with an age of about 300,000 years. The best estimate of the distance is around 100 light-years, so is quite close in astronomical terms. Richard J. Edgar (edgar@wisp4.physics.wisc.edu) University of Wisconsin--Madison, Department of Physics "It all depends, of course, upon whether or not it depends or not, of course, if you take my meaning" ------------------------------ Date: 21 Jan 1993 22:46 UT From: Ron Baalke Subject: Galileo Update - 01/21/93 Newsgroups: sci.space,sci.astro,alt.sci.planetary Forwarded from Neal Ausman, Galileo Mission Director GALILEO MISSION DIRECTOR STATUS REPORT POST-LAUNCH January 15 - 21, 1993 SPACECRAFT 1. On January 15, the Dual Drive Actuator (DDA-5) Turn E sequence memory load was uplinked to the spacecraft without incident. This sequence covers spacecraft activities from January 18, 1993 through January 20, 1993 and includes DDA hammer window opportunities throughout the period. 2. On January 15, one 360 pulse hammer sequence was executed with the HGA (High Gain Antenna) motor temperature at 36.2 degrees C. This hammer sequence utilized two different hammer frequencies (1.25 hertz and 1.875 hertz). 3. On January 18, one 360 pulse hammer sequence was executed with the HGA motor temperature at 34.0 degrees C. This hammer sequence utilized two different hammer frequencies (1.25 hertz and 1.875 hertz). Real-time commands were then sent to reacquire celestial reference at the completion of the star scanner checkout. 4. On January 18, the EE-12A (Earth-Earth #12A) sequence memory load was uplinked to the spacecraft without incident. This sequence covers spacecraft activities from January 20, 1993 through January 23, 1993. 5. On January 19, as part of DDA-5 Turn E sequence activities, the turn to a 9-degree off-sun attitude started at approximately 1802 UTC and completed at 1822 UTC. After approximately one hour at the new attitude, hammering of the HGA motors commenced. Five 360 hammer pulse sequences were sent beginning at 1935 UTC and ending at 2349 UTC. The motor hammering sequences were executed with the HGA motor temperature at 25.5 degrees C, 21.4 degrees C, 19.3 degrees C, 17.2 degrees C, and 15.2 degrees C. These hammer sequences utilized two different hammer frequencies (1.25 hertz and 1.875 hertz). There continues to be no substantial ballscrew rotation since the major hammering on December 29, 1992. Approximately 5 hours after the motor hammering activity terminated, real-time commands were sent to reacquire celestial reference after the star scanner checkout completed. 6. On January 20, a periodic RPM (Retro-Propulsion Module) 10-Newton thruster maintenance activity was performed; all 12 thrusters were "flushed" during the activity. Spacecraft activity throughout the period was normal. 7. On January 20, a SITURN was scheduled in the EE-12 sequence. The purpose of the SITURN was to ensure the spacecraft was at the EE-12 attitude in the event that the DDA-5 Turn E sequence was not executed on the spacecraft. 8. During the period from January 20 through January 21, a navigation cycle was performed. This navigation cycle provided near-continuous acquisition of two-way doppler and ranging data during four consecutive passes of the spacecraft over DSS-43 (Canberra 70 meter antenna), DSS-63 (Madrid 70 meter antenna), DSS-14 (Goldstone 70 meter antenna), and then back to DSS-43. 9. On January 20, real-time commands were sent to enable the master critical enable and to lift AACS (Attitude and Articulation Control Subsystem) write protects in preparation for the sequence controlled Clock System Identification (CLKSYSID) activity. Upon completion of the CLKSYSID, real-time commands were then sent to restore the AACS write protects and to disable the master critical enable. 10. On January 21, Cruise Science Memory Readouts (MROs) were performed for the Extreme Ultraviolet Spectrometer (EUV). Preliminary analysis indicates the data was received properly. 11. On January 21, numerous attitude control subsystem calibrations were performed including a Star Scanner A calibration, wobble identification, gyro drift calibration, spin detector A calibration, Spin Bearing Assembly (SBA) drag torque calibration, accelerometer calibration, and a Scan Actuator Subassembly (SAS) friction test. The data was collected nominally and analysis is in progress. 12. The AC/DC bus imbalance measurements have not exhibited significant change (greater than 25 DN) throughout this period. The AC measurement reads 18DN (4.1 volts). The DC measurement reads 153DN (18.0 volts). These measurements are consistent with the model developed by the AC/DC special anomaly team. 13. The Spacecraft status as of January 21, 1993, is as follows: a) System Power Margin - 74 watts b) Spin Configuration - Dual-Spin c) Spin Rate/Sensor - 3.15rpm/Star Scanner d) Spacecraft Attitude is approximately 8 degrees off-sun (leading) and 39 degrees off-earth (leading) e) Downlink telemetry rate/antenna- 1200bps(coded)/LGA-1 f) General Thermal Control - all temperatures within acceptable range g) RPM Tank Pressures - all within acceptable range h) Orbiter Science- Instruments powered on are the EUV, EPD, MAG, HIC, and DDS i) Probe/RRH - powered off, temperatures within acceptable range j) CMD Loss Timer Setting - 120 hours Time To Initiation - 96 hours UPLINK GENERATION/COMMAND REVIEW AND APPROVAL: 1. The Dual Drive Actuator (DDA-5) Part E sequence memory load was approved for transmission by the Project on January 15, 1993. This sequence covered High Gain Antenna (HGA) motor hammering activities from January 18, 1993 to January 20, 1993. As with previous hammering activities, individual sets of hammering commands were approved as required prior to being uplinked to the spacecraft. 2. The EJ-1 (Earth-Jupiter #1) Cruise Plan was approved by the Project on January 19, 1993. This plan covers spacecraft activities from April 12, 1993 to June 15, 1993. GDS (Ground Data Systems): 1. A Galileo MVT (Mission Verification Test) was performed on January 14, 1993, using DSS-14 (Goldstone). The purpose of the test was to evaluate the new Station Communications Processor's (SCP) ability to support Galileo. This test exercised telemetry and monitor for Galileo. The SCP worked well for all Galileo telemetry rates and monitor. Two liens were identified during MVT testing: (1) unable to perform dual stream 134.4 kbps data test due to unavailability of DSN (Deep Space Network) resources; (2) unable to use MCCC (Mission Control and Computing Center) SIM long loop due to ARAs (Area Routing Assembly) being prime. These liens will be demonstrated as working in SOAK by performing GDS tests on the specific lien. The SCP is expected to go into SOAK for Galileo support on February 5, 1993. TRAJECTORY As of noon Thursday, January 21, 1993, the Galileo Spacecraft trajectory status was as follows: Distance from Earth 31,623,600 km (0.21 AU) Distance from Sun 168,800,400 km (1.13 AU) Heliocentric Speed 129,300 km per hour Distance from Jupiter 730,891,900 km Round Trip Light Time 3 minutes, 32 seconds SPECIAL TOPIC 1. As of January 21, 1993, a total of 64682 real-time commands have been transmitted to Galileo since Launch. Of these, 59329 were initiated in the sequence design process and 5053 initiated in the real-time command process. In the past week, 18743 real time commands were transmitted: 18743 were initiated in the sequence design process and none initiated in the real time command process. Major command activities included commands to uplink DDA-5E sequence memory load, hammer the HGA motors, reacquire celestial reference, uplink the EE-12A sequence memory load, and perform CLKSYSID activities. ___ _____ ___ /_ /| /____/ \ /_ /| Ron Baalke | baalke@kelvin.jpl.nasa.gov | | | | __ \ /| | | | Jet Propulsion Lab | ___| | | | |__) |/ | | |__ M/S 525-3684 Telos | Every once in a while, /___| | | | ___/ | |/__ /| Pasadena, CA 91109 | try pushing your luck. |_____|/ |_|/ |_____|/ | ------------------------------ Date: 21 Jan 93 20:47:31 GMT From: Larry Wall Subject: Making Orbit 93 - The Delta Clipper Program Newsgroups: sci.space In article <19862@mindlink.bc.ca> Bruce_Dunn@mindlink.bc.ca (Bruce Dunn) writes: : The vehicle enters nose first. The re-entry aerodynamics of the vehicle are : derived from the very large body of data which is available on missile : warhead re-entry aerodynamics. The angle of attack of the vehicle is : controlled to minimize thermal loading. The vehicle has a 1200 to 1500 : nautical mile cross range. Deacceleration is 1.1 g maximum during descent. : On descent, the vehicle goes subsonic at 60,000 feet altitude, and the : engines are then started and idled. At 5000 to 10,000 feet altitude, the : vehicle is rotated base down. How do they guarantee they don't get upside-down-spraycan syndrome? Not only are they going to have to pump hydrogen and oxygen from the FAR ends of the tanks, but they have to make sure they don't get bubbles in the line while rotating, and you can't do that if the tank is less than half full without having inlets on the sides of the tank, as well as top and bottom. (Controlling slosh during rotation is no picnic either.) Anybody know how they plan to do it? For instance, with lots of smart inlet valves that know when to keep their mouths shut? Or maybe the engines are robust enough not to care about "burps" when idling? I suppose you could just pressurize above the triple points of H2 and O2, and then you don't have to worry about it... :-) Larry Wall lwall@netlabs.com ------------------------------ Date: Thu, 21 Jan 1993 10:06:25 GMT From: Dennis Newkirk Subject: Russians plan 540 day Mir mission Newsgroups: sci.space Flight International quoted official Russian sources confirming rumors that the crew to be launched to Mir in late 1993 will probably include a doctor with the objective of staying on the station for 540 days. The mission would last through the visiting French flight scheduled for mid-1994, and they would be joined by the NASA astronaut in early '95 to round out the last 100 or so days. They hope to be returned by the US Shuttle in 1995 after the planned docking with Mir and delivery of the replacement Mir crew. This plan presumably takes advantage of NASA's post flight medical analysis skills for what would be the longest manned spaceflight ever. Flight International also reports that the 540 day mission was planned earlier to succeed the year long mission in 1988, but was delayed by the policy change to fly 5-6 month missions to increase productivity of the crew. Exactly what caused the latest change in policy is unclear, but I suspect it is intended to entice NASA into long term missions using Mir or Mir 2 studying life sciences. Also, remember to watch the news for the Soyuz TM-16 launch this Sunday (Jan 24.). CNN usually allocates 10 or 15 seconds of their precious time for a tapeed Soyuz launch. Current plans are for the Soyuz TM 16 crew to be replaced by the Soyuz TM-17 joint French Mission scheduled to be launched July 1. There are still a number of other nations interested in visiting flights to Mir so the Russians immediate problem may be to much demand to satisfy within the constraints of their current infrastructure. The Soyuz TM-18 in late 1993 will also probably be a joint German flight. Assuming the routine 6 month visiting crew interval is unchanged this leaves late 1993, mid 1994, and late 1994 Soyuz missions undefined before the joint NASA flights begin. Dennis Newkirk (dennisn@ecs.comm.mot.com) Motorola, Land Mobile Products Sector Schaumburg, IL ------------------------------ Date: Thu, 21 Jan 1993 20:11:04 GMT From: "Robert F. Drury" Subject: Sabatier reactor? (was Re: Oxygen in Biosphere 2) Newsgroups: sci.space In article , ggm@brolga.cc.uq.oz.au (George Michaelson) wrote: > > John Finn writes: > > >Manufactured by Hamilton Standard > >CO2 + 4(H2) => CH4 + 2(H2O) (methane formation) > >conditions: 950 F on a ruthenium/alumina catalyst > >full configuration for 8-man crew (4 units + spares, etc.): > > 1096 lbs, avg. 395 watts, 34 cubic feet > > Does CH4 have any role inside a space station apart from making it > smell farty? > > refrigerant gas? > cooking :-) yes... I know it makes C02... > > Failing which would venting to space or using as supplement to position holding > rocketry be worth the effort? > > -George > -- > George Michaelson > G.Michaelson@cc.uq.oz.au The Prentice Centre | There's no market for > University of Queensland | hippos in Philadelphia > Phone: +61 7 365 4079 QLD Australia 4072 | -Bertold Brecht Methane is an odorless gas; the smell referred to arises from various aldehydes, ketones, and carboxylic acids present in the "natural" product. I'm more curious as to how the CO2 is separated from the O2; under these conditions hydrogen reacts vigorously with oxygen and would use large amounts of both to reduce a small amount of CO2 unless some preconcentration takes place. Standard Disclaimer--My opinions are my own, and do not represent those of my employer. R.F.Drury Du Pont Electronics Internet drury@esvax.dnet.dupont.com ------------------------------ End of Space Digest Volume 16 : Issue 071 ------------------------------