Date: Sun, 11 Oct 92 05:02:51 From: Space Digest maintainer Reply-To: Space-request@isu.isunet.edu Subject: Space Digest V15 #307 To: Space Digest Readers Precedence: bulk Space Digest Sun, 11 Oct 92 Volume 15 : Issue 307 Today's Topics: Ariane V.54 / Galaxy VII Bootstrap hardware for LunaBase (3 msgs) Mars Observer info? Pioneer Venus Update - 10/09/92 (End of Mission) Switching ALSEP back on (was Re: another sad anniversary) Telepresence Toshiba vs. Chaparral 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: 11 Oct 92 01:02:55 GMT From: Dean Adams Subject: Ariane V.54 / Galaxy VII Newsgroups: rec.video.satellite,sci.space ARIANESPACE FLIGHT 54 The 54th Ariane launch is scheduled to place the Hughes Communications GALAXY VII satellite into a geostationary transfer orbit adapted for the PVA (Perigee Velocity Augmentation) procedure, using an Ariane 42P launch vehicle equipped with 2 solid strap-on boosters (PAP). This will be the 3rd flight of an Ariane 4 in the 42P configuration. It will be launched from the Ariane launch complex ELA 2, in Kourou -- French Guiana. The launch vehicle performance requirement for this mission is 3,043 kg (6,710 lb), of which 2,968 kg (6,545 lb) represents the satellite mass. The total vehicle mass at liftoff is 323,161 kg. Required Orbit Characteristics: Perigee Altitude ..... 200 km Apogee Altitude ...... 27,673 km at injection (prior to PVA) Inclination .......... 7 degrees The Ariane 42P lift-off for Flight 54 is scheduled on Thursday October 15, 1992, as soon as possible within the following launch window: Kourou Time GMT (10/16/92) Washington, DC 21:14 - 22:05 00:14 - 01:05 20:14 - 21:05 LAUNCH VEHICLE: Ariane 42P. This is a three-stage liquid fueled launcher with solid fueled strap-on boosters. The first stage (L220) is built by Aerospatiale, and is powered by 4 liquid fueled Viking V engines. The second stage (L33) is built by MBB Erno and is powered by a single Viking IV engine. Both the Viking IV and V engines are manufactured by SEP. The first and second stages use a biliquid UH25/N2O4 fuel. The third stage is built by Aerospatiale and is the H10 "plus", with larger fuel tanks and increased performance over past models. It uses a cryogenic H2/O2 fueled HM-7B engine built by SEP. The two strap-on boosters (PAP) are built by BPD and use a solid Flexadrine propellant. The fully assembled launch vehicle stands 54.5 meters high on the pad. It uses the Ariane Short payload fairing. Flight Profile: +01:31 Solid strap-on booster jettison +03:27 First stage separation +03:30 Second stage ignition +04:35 Fairing jettison +05:30 Second stage separation +05:43 Third stage ignition +18:11 Third stage shutdown / orbit injection +20:00 GALAXY VII separation +22:46 End of Ariane mission 52 Perigee Velocity Augmentation (PVA): PVA is a procedure which optimizes the combined performance of launch vehicle and satellite to increase the on-orbit life of the satellite. For this mission, the Ariane 42P will lift around 280 kg of additional satellite propellants, to an apogee of 27,600 km instead of the GTO apogee of 35,975. The Galaxy VII satellite will use its apogee motor at the 3rd and 6th perigee to raise the apogee to the altitude normally used for circularization of the orbit. The on-orbit life increase is due to the fact that the satellite apogee motor does not need to propel the dry Ariane 3rd, which will remain in the lower orbit of 200 x 22,673 km. This procedure can only be used by satellites equipped with a liquid bi-propellant apogee motor (which can be restarted), and whose tank capacity allows fuel in excess of that necessary for a standard GTO. Due to the small inclination of the Ariane mission (7 degrees), this capacity is often available when the satellites are built to be launched from sites further away from the equator. This combination of HS-601/Ariane 42P/PVA allows an increase of more than one year of orbital life for the commercial use of the satellite. PAYLOAD: Galaxy VII is the first satellite with a combined C-band and Ku-band capability in the Galaxy fleet owned by Hughes Communications. It is also the first Arianespace launch of the type HS-601 three-axis stabilized satellite manufactured by Hughes Aircraft Company. Total mass at lift-off .... 2,968 kg Mass at GEO insertion ..... 1,680 kg Dry mass .................. 1,303 kg On-board power ............ 4,700 W (end of life) Nominal lifetime .......... 13.5 years Span of solar panels ...... 26.5 m On-Orbit position ......... 91 degrees west, over the Galapagos Islands. Transmission capacity: 24/30 Ku-band transponders of 50W each. 24/30 C-band transponders of 16W each. In-flight operations: Apogee motor ignition for PVA maneuver is at about 24 hrs after launch at the 3rd perigee, and about 60 hrs after launch at the 6th perigee. First apogee motor firing is at the 12th apogee, about 5 days after launch. Further firing will be done at 14th and 15th apogee. Deployment of solar panels .... about 10 days after launch. LAUNCH COVERAGE: All Ariane missions are broadcast live via satellite from Kourou. Coverage begins at 30 minutes before launch and continues until all payloads have been deployed. This mission will likely be carried on Galaxy 6, however it could end up being located on a different satellite such as Galaxy 2. -{ Dean Adams }- ------------------------------ Date: 10 Oct 92 23:37:56 GMT From: "Allen W. Sherzer" Subject: Bootstrap hardware for LunaBase Newsgroups: sci.space In article <1992Oct10.231941.1467@techbook.com> szabo@techbook.com (Nick Szabo) writes: >More than enough money _where_? The SEI budget is in the $10's... Nick, nobody is talking anything about SEI. The question was raised of how much a particular project would cost. The estimate you give was wildly in error since you failed to account for the cost effects of a larger market. Your giveing the cost of the project if it is never executed which is rather pointless. Even there you are way off base since the cost of an unexecuted project is $0.00. If the project where executed, launch costs (among other costs) would be an order of magnitude lower than you estimate. Any estimate which fails to account for this was either made by a fool or somebody who just doesn't understand cost estimating. I just got done putting together a cost estimate for a project we are bidding on. If I used your methods of cost estimating, we wouldn't win any contracts. I therefore very much hope your employer doesn't allow you to estimate project costs or write proposals. >Have I finally treaded into the central segment of a mass delusion... Not a mass delusion, only you deluding yourself. Allen -- +---------------------------------------------------------------------------+ | Allen W. Sherzer | "A great man is one who does nothing but leaves | | aws@iti.org | nothing undone" | +----------------------197 DAYS TO FIRST FLIGHT OF DCX----------------------+ ------------------------------ Date: 11 Oct 92 00:02:46 GMT From: Henry Spencer Subject: Bootstrap hardware for LunaBase Newsgroups: sci.space In article <1992Oct10.231941.1467@techbook.com> szabo@techbook.com (Nick Szabo) writes: >>As Allen pointed out, there's more than enough money there >>for commercial development of a dozen new launch systems. > >More than enough money _where_? The SEI budget is in the $10's >of millions. Commercial funding for moon ventures is zero. Nick, that's not what we were talking about. (If you wonder why I usually ignore your postings, it's because any debate with you seems to be fraught with these sudden changes of subject whenever you start losing.) We were talking about your bloated cost estimates for the projects you don't like. Nobody will ever quote a hundred billion dollars to launch a moon base (or whatever) at current launch prices, because a fraction of that amount of money is enough to build much cheaper launchers. At the very least, if you want an *honest* comparison rather than transparently-biased salesmanure for your own projects, you should discount today's launch prices by a substantial factor (2 at least, more probably 5 or 10) for economies of scale in bulk use of existing launchers. Some sort of allowance for the development of whole new launch systems would be more realistic, though. For ten billion, we could fund three SSTO-sized projects at 100% overrun as far as flight demonstrators, and almost certainly one of them would work, destroying the entire basis for your cost estimates. Any combination of irrationality and bloat capable of maintaining prices despite such an enormous increase in volume would be potent enough to have similar effects on your favorite projects too. -- MS-DOS is the OS/360 of the 1980s. | Henry Spencer @ U of Toronto Zoology -Hal W. Hardenbergh (1985)| henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: Sun, 11 Oct 1992 08:11:02 GMT From: Nick Szabo Subject: Bootstrap hardware for LunaBase Newsgroups: sci.space In article <1992Oct10.233756.12563@iti.org> aws@iti.org (Allen W. Sherzer) writes: >In article <1992Oct10.231941.1467@techbook.com> szabo@techbook.com (Nick Szabo) writes: > >>More than enough money _where_? The SEI budget is in the $10's... > >Nick, nobody is talking anything about SEI. The question was raised of how >much a particular project would cost. The estimate you give was wildly >in error since you failed to account for the cost effects of a larger market. > That's strange, we just had a huge thread about SEI's FLO, which you flamed me for daring to criticize. It's also interesting that you deleted the second part of that sentence, which pointed out business investment would not be a source of funds. (Repeating point that should be obvious for third time in a row, for Allen's benefit): The whole point of mentioning SEI's budget is there _isn't_ any significant market in the political/contracting arena. That's what the NASA contractor moon-related work (and ads) are focused on. There isn't any paying market from the point of view of business, either, whether the project costs $100 billion or $1,000 billion. Business just does not invest in schemes that require multiple layers of new technologies assumed to be orders of magnitude cheaper than what previous projects have accomplished. Any investor with those $$$ will laugh you right out of their office, unless you've got a juicy NASA contract in your hand. It won't matter how many earnest space fans you can gather to pile on the critics. If you don't beleive me, try it. Or at least start reading what the biz rags like the Economist and Wall Street Journal have to say about space development. The first thing you will realize is that selling a commercial project is _very_ different from the traditional skill of selling the government and government contractors. They don't care how popular the project is, and they do care how expensive it is; almost 180 degrees opposite of governemntal concerns. Furthermore, your thesis (>volume => If the project where executed, launch costs (among other costs) would be >an order of magnitude lower than you estimate. Last you were talking it was _two_ orders of magnitude. Make up your mind! (Notice how Allen avoids posting actual numbers, and is quick to flame those who dare mention costs. That will really impress the investors, Allen :-) >Any estimate which fails to >account for this was either made by a fool You're right. I am a fool for repeating over and over the same common-sense business facts to folks who have their minds made up, and really couldn't give a damn about business anyway, but just want to use it to justify the same old failed junk. -- Nick Szabo szabo@techboook.com Hold Your Nose: vote Republocrat //////// Breathe Free: vote Libertarian ------------------------------ Date: Sun, 11 Oct 1992 07:17:37 GMT From: David Knapp Subject: Mars Observer info? Newsgroups: sci.space,alt.sci.planetary In article prb@access.digex.com (Pat) writes: >In article <1992Oct5.193214.21355@ucsu.Colorado.EDU> knapp@spot.Colorado.EDU (David Knapp) writes: >> >>Instruments: >> >>Gamma Ray Spectrometer; studies surface chemicals/composition >>Mars Observer Camera; photographs surface > >>Thermal Emission Spectrometer; measures IR (I'm guessing primarily surface) >>Pressure Modulator Infrared Radiometer; measures the atmospheric emission >>Mars Observer Laser Altimeter; gives higher resolution topographical info >>Magnetometer/Electron Reflectometer; investigates Martian magnetic fields. >> >> >>The MOC (camera) has <*2* meter resolution! (loud gasp of amazement.) This will >>allow for detailed study of mass transport over the surface with seasonal >>variations. (and some very impressive photos indeed.) >> > > >MO is currently scheduled only to image mars. i talked to some >planetary scientists who were hoping to wheedle some imaging time >to look at phobos and deimos. if so, what are some of the considerations. > >i was thinking along the lines of: > > 1) what kind of resolution will they get? > > 2) will they be able to image all sides. > > 3) would they be able to use the other instruments as well. > > 4) what kind of impact will this have on spacecraft operations. > i imagine MO is going to go into a sun synchonous polar orbit, > so to get more uniform imaging and keep power levels uniform. > would imaging the moonlets, eat up thruster gas or impede > solar collection? > >just a few questions. > >thanks The imaging camera is actually only a linear array, sweeping up images as the planet passes beneath the s/c. My hunch is that due to geometries of the orbit and the camera, viewing of moons won't be possible. -- David Knapp University of Colorado, Boulder Perpetual Student knapp@spot.colorado.edu ------------------------------ Date: 11 Oct 92 13:39:24 GMT From: Ron Baalke Subject: Pioneer Venus Update - 10/09/92 (End of Mission) Newsgroups: sci.space,sci.astro,alt.sci.planetary PIONEER VENUS STATUS REPORT October 9, 1992 End of Mission On October 8, 1992 at 12:30 PM PDT, the 70 meter antenna in Goldstone, California (DSS-14), failed to detect a signal from the Pioneer Venus spacecraft after periapsis on orbit 5056. It was assumed that the either the drag of the atmosphere had knocked the spacecraft's High Gain Antenna (HGA) off Earth point, or the spacecraft did not survive its last trip through the upper atmosphere of Venus. DSS-14 and DSS-43 (70 meter antenna in Canberra, Australia) continued to search for a signal from the spacecraft for several more hours, including attempts to acquire a signal from the forward Omni antenna, but still no signal was detected. Pioneer Venus end of mission was declared on October 8, 1992 at 17:55 PM PDT by the Pioneer Project Controller. The spaceraft's remains will continue to orbit Venus for a short while, but no data can be collected without a radio signal. Here's a recap of the spacecraft events from the past week: October 2 - The sixth altitude raising maneuver was successfully performed and raised the periapsis from 132.9 km to 141.7 km. October 3 - In an attempt to reorient the spacecraft during apoapsis between orbits 5050 and 5051, Pioneer Venus apparently ran out of fuel. After firing 90 pulses, only a 1 degree of precession was achieved. The propellant tank pressure dropped by two data numbers to 54.1 psi, indicating that pressurant gas instead of fuel was expelled. October 5 - Pioneer Venus was spun up with full thruster response for 150 seconds on orbit 5053. The resultant near-doubling of spin rate will reduce reorientation suffered from drag at periapsis and will facilitate use of the HGA through the next several orbits if the spacecraft survives the deeper penetrations of the atmosphere. It was also suspected that 4 oz of propellant still remained and the spin up would aid in moving the propellant towards the thrusters. October 6 - Pioneer Venus survived periapsis on orbit 5054, at an altitude of 130.8 km and a drag of 0.91 m/s. October 7 - Pioneer Venus survived periapsis on orbit 5055, at an altitude of 128.9 km and a drag of 1.9 m/s. Attempts to reorient the spacecraft with thrusters after periapsis was 25% effective. At 22:25 PM PDT, a pulsed apoapsis manuever of 200 pulses resulted in a gain of 1 kilometer in periapsis altitude. The tank pressure held at 52.6 psi, indicating that propellant probably still existed. October 8 - DSS-14 failed to detect any signal from the spacecraft after periapsis on orbit 5056. When the signal acquistion continued to be unsuccessful for several more hours, the end of the mission for the Pioneer Venus spacecraft was declared. The estimated periapsis altitude of the final orbit was 128.0 km, and the final estimated drag was at 2.5 m/s. ___ _____ ___ /_ /| /____/ \ /_ /| Ron Baalke | baalke@kelvin.jpl.nasa.gov | | | | __ \ /| | | | Jet Propulsion Lab | ___| | | | |__) |/ | | |__ M/S 525-3684 Telos | Einstein's brain is stored /___| | | | ___/ | |/__ /| Pasadena, CA 91109 | in a mason jar in a lab |_____|/ |_|/ |_____|/ | in Wichita, Kansas. ------------------------------ Date: 7 Oct 92 19:37:27 GMT From: Marcus Hall Subject: Switching ALSEP back on (was Re: another sad anniversary) Newsgroups: sci.space In article henry@zoo.toronto.edu (Henry Spencer) writes: >In article <1689@tnc.UUCP> m0102@tnc.UUCP (FRANK NEY) writes: >>Is there any way to turn ALSEP back on once we get the ground station >>set up properly? Or was it a no-return type of prodedure? > >Such turnoff procedures are usually irreversible, I believe, to minimize >the chances of dying hardware later reversing them on its own. I'm not >sure about ALSEP in particular. For what it's worth, on the Kennedy Space center tour, there is a display with a flight qualified LEM and CM/SM. The tour guide mentioned that the landing sites had left instruments on the moon [undoubtedly ALSEP] that had been switched off but could be switched back on whenever more data was wanted. Now, I wouldn't put a lot of faith in this statement, but they did seem to know alot about what they were talking about on other things. I only mention it here for what it's worth... marcus hall ------------------------------ Date: 11 Oct 92 04:48:10 GMT From: John Roberts Subject: Telepresence Newsgroups: sci.space -From: gary@ke4zv.uucp (Gary Coffman) -Subject: Re: Telepresence -Date: 10 Oct 92 14:42:41 GMT -Organization: Gannett Technologies Group -In article <9210070147.AA09594@cmr.ncsl.nist.gov> roberts@CMR.NCSL.NIST.GOV (John Roberts) writes: -> -> Predictive Display for Teleoperation With Delay -> -> ...The simulator displays a phantom -> image of the robot superimposed on the delayed "real" monitoring image of -> the robot. The phantom responds to control signals immediately -- that is, -> without transmission delay. Its motion predicts that of the real robot. -> After the transmission delay, the real image of the robot follows the motion -> of the phantom image. -After successfully maneuvering the phantom image, the operator sits back -and watches the delayed image of the rover slowly fall into a subsidence -hidden from the scan. The screen image is replaced by the words "GAME -OVER. INSERT $1 BILLION TO PLAY AGAIN" -Gary Which is why all the serious Mars rover designs have safety systems built in - such as the wheel position sensors on Rocky IV, and a few even have mechanisms to right themselves, such as Go-For. There are also many envisioned applications of teleoperation which are *not* rovers. The demonstration project described in the NASA Tech Briefs article involved a robot arm. I think we all agree that juggling by teleoperation is going to be a formidable task for a long time. (On the other hand, some dynamic operations are much simpler - judging from my very limited experience playing with a time-delay teleoperation demonstrator, the "running start" bulldozer maneuvers you've described in previous years might actually be practical.) It would be interesting to use this feedback system on a rover - the cameras would be on the rover itself, so the control system would project a phantom rover in front of you, then as the return signal comes back, the landscape starts moving, and the phantom rover moves from background to foreground in the image, approaching the "screen" until it vanishes. (That's for a long feedback path such as a Mars mission - an experienced operator of a lunar rover might be able to maintain continuous motion much of the time, so the phantom would be continually in sight.) John Roberts roberts@cmr.ncsl.nist.gov ------------------------------ Date: 11 Oct 92 03:42:33 GMT From: Akmal Khan Subject: Toshiba vs. Chaparral Newsgroups: rec.video.satellite,sci.space All the flashy LEDs notwithstanding, can anyone contrast the Toshiba TRX-80/TRX-100 IRDs with the Chaparral Monterey 70 and the Chaparral CR110 receivers? Am I making a huge mistake even considering buying one of these? ---- Akmal Khan System Software Development Silicon Graphics Computer Systems akmal@sgi.com ------------------------------ End of Space Digest Volume 15 : Issue 307 ------------------------------