Return-path: X-Andrew-Authenticated-as: 7997;andrew.cmu.edu;Ted Anderson Received: from hogtown.andrew.cmu.edu via trymail for +dist+/afs/andrew.cmu.edu/usr11/tm2b/space/space.dl@andrew.cmu.edu (->+dist+/afs/andrew.cmu.edu/usr11/tm2b/space/space.dl) (->ota+space.digests) ID ; Sat, 11 May 91 01:53:40 -0400 (EDT) Message-ID: <4c-sPQW00WBwM3eE4Q@andrew.cmu.edu> Precedence: junk Reply-To: space+@Andrew.CMU.EDU From: space-request+@Andrew.CMU.EDU To: space+@Andrew.CMU.EDU Date: Sat, 11 May 91 01:53:33 -0400 (EDT) Subject: SPACE Digest V13 #524 SPACE Digest Volume 13 : Issue 524 Today's Topics: Re: Why the space station?y Re: Saturn V and the ALS Re: Holding Down an Atmosphere (was Re: Teraforming Venus?) Re: Ethics of Terraforming (was Re: Terraforming Venus) Re: Saturn V and the ALS NASA Prediction Bulletins: Space Shuttle NASA Prediction Bulletin Format YOUR HELP NEEDED URGENTLY TO SAVE SPACE SCIENCE! Administrivia: Submissions to the SPACE Digest/sci.space should be mailed to space+@andrew.cmu.edu. Other mail, esp. [un]subscription requests, should be sent to space-request+@andrew.cmu.edu, or, if urgent, to tm2b+@andrew.cmu.edu ---------------------------------------------------------------------- Date: 10 May 91 04:05:26 GMT From: stanford.edu!agate!lightning.Berkeley.EDU!fcrary@decwrl.dec.com (Frank Crary) Subject: Re: Why the space station?y In article <28534@hydra.gatech.EDU> ccoprmd@prism.gatech.EDU (Matthew DeLuca) writes: >The risks may be somewhat greater, with the extra 'junk' in the are, but keep >in mind that the Shuttle should be able to do a far better job of docking >(granted, it's never been tried) than a Soviet unmanned spacecraft. With >human operators on the scene, a situation similar to the Progress incident >could never arise; the crew in the station, the crew on the orbiter, and >the ground controllers could all catch the situation in time and do something >about it...one of the advantages to man in space. > While the pilot of the shuttle will be much better than the unmanned Progress craft, the shuttle is also larger and less manuvrable than Progress. Progress (and the Soyuz manned craft) have an acceleration of up to 0.615 m/s^2. The shuttle accerleates, on OMS, at 0.073 m/s^2. Also just the SIZE of a shuttle orbiter make it awkard in close proximity of a station. >Also, I wouldn't put a lot of trust in Soviet docking abilities; they've been >notoriously deficient in this area for thirty years. Over 30 years they may be deficient, but they have been very good in the the more recient past. All docking attempts to the Mir station have been successful (manned dockings that is). The last manned docking failure in the soviet program was Soyuz-T 8 in April 1983. Since then they have made 17 successful dockings. However, they do not always dock on the first pass. Frank Crary UC Berkeley ------------------------------ Date: 7 May 91 22:27:30 GMT From: orca!bambam!bpendlet@uunet.uu.net (Bob Pendleton) Subject: Re: Saturn V and the ALS In article <17529@celit.fps.com>, dave@fps.com (Dave Smith) writes: > In article <350.2822830C@nss.FIDONET.ORG> Paul.Blase@nss.FIDONET.ORG (Paul Blase) writes: > >Several things that I think that most people are missing about the ALS. > > > >The ALS is NOT an attempt to build a latest, state-of-the art, > >Lamborghini-class launch vehicle. Rather, it is a "Ford Pickup" class > >hauler. The end goal is minimization of launch costs, NOT maximization > >of performance. To this end: > > No, nobody is missing anything. You're just on different wavelengths. > You are saying the NASA says the ALS will be a "pick-em-up truck." Because > it's built to perform as a pick-em-up truck it will be cheap. > > What everyone else is saying is "The Shuttle was going to be a pick-em-up > truck. Why is ALS different?" The only answer I've seen you give to date > is "NASA says so." There is one reason to believe that ALS will be close to what it is claimed to be: The Air Force says so. There is some big general somewhere, along with a few little generals, a bunch of colonels, majors, captains, ... Whose next promotion depends on ALS being exactly what they say it will be. The Air Force works on an "up or out" system. If you don't move up in rank you wind up out of the Air Force. So there is strong motivation to do what you said you would do. ALS is being designed so that all launch pad servicing can be done without a service tower. It is being designed that way because a general said to do it that way. He said it because service towers are expensive and using them leads to expensive prelaunch operations. The U.S Air Force are the people who brought you the Atlas and Titan boosters, the Minute Man I, II, and III, and the Peacekeeper missiles. I won't claim that the Air Force doesn't make mistakes. Their cost over runs are legendary. But they have produced a series of operational rocket based systems. And they have operated those systems since before there WAS an USAF. Of course NASA can still screw it up. -- Bob Pendleton, speaking only for myself. bpendlet@dsd.es.com or decwrl!esunix!bpendlet or hellgate!esunix!bpendlet Tools, not rules. ------------------------------ Date: 6 May 91 13:59:08 GMT From: hpfcso!mll@hplabs.hpl.hp.com (Mark Luce) Subject: Re: Holding Down an Atmosphere (was Re: Teraforming Venus?) / hpfcso:sci.space / drwho@athena.mit.edu (Jonathan Monsarrat) / 7:21 pm May 3, 1991 / Ganymede has about 1/7 of the Earth's gravity even though it's big. This is because it is mostly ice. If a lot of water vapor or atmosphere of some sort were created by a. melting a lot of ice b. pummeling it with ice comets does anyone know how long it would take for the atmosphere to bleed off? How much gravity does a body need to have an atmosphere anyway? > Ganymede is evidently large enough to have an atmosphere, since Titan > has about the same surface gravity and has an atmosphere about half > again as dense as Earth's. My question would be, why does Titan have > such a thick atmosphere while Ganymede does not? And if it were a satellite (Ganymede), would its focus (Jupiter) steal the atmosphere away anyway? Much appreciation for any insight into this. Thank you! -Jon Monsarrat jonmon@cadence.com drwho@athena.mit.edu ---------- ------------------------------ Date: 8 May 91 02:38:36 GMT From: VAX1.CC.UAKRON.EDU!mcs.kent.edu!usenet.ins.cwru.edu!agate!headcrash.Berkeley.EDU!fcrary@tut.cis.ohio-state.edu (Frank Crary) Subject: Re: Ethics of Terraforming (was Re: Terraforming Venus) In article <1991May7.163250.2333@engin.umich.edu> kcs@sso.larc.nasa.gov (Ken Sheppardson) writes: > Is there anyone else out there who questions the ethics of tampering > with other planets (with or without the presence of life) to make them > more 'earthlike'? I'm all for non-intrusive exploration and the > construction of free-floating stations/colonies, but given our history > of 'Manifest Destiny', rain forest destruction, ozone depletion, strip > mining, etc, I feel like we should take a hands off approach to space. In fact Chirs McKay of NASA/Ames has written several papers on the ethics of terraforming Mars. One thing he points out is that, by making a dead planet livable (though not necessarily like Earth), we would INCREASE the number of environments for living creatures (exactly the reverse of the destruction of the rain forests.) Also, there is reason to believe that, although Mars is now a dead planet, it once had a thick atmosphere and a warmer climate. Potentially, life could have evolved on Mars, and died as the climate changed. If this is the case, terraforming Mars would RESTORE a previously destroied climate. By the way, you put 'Manifest Destiny' in a class with rain forest destruction ozone depletion, strip mining, etc.. While there were many unfortunate and very negative effects of the United States expansion into the west, I do not see the attitude of "manifest destiny" as their cause. As far as I understand it, "manafest destiny" was simply the belief that the growth of the US was clearly and obviously what was going to happen, and where the future would be. I believe this same attitude could be applied to space, and would not necessarily cause problems. Frank Crary UC Berkeley ------------------------------ Date: 8 May 91 01:58:49 GMT From: haven.umd.edu!uvaarpa!murdoch!astsun9.astro.Virginia.EDU!gsh7w@louie.udel.edu (Greg Hennessy) Subject: Re: Saturn V and the ALS In article <1991May7.232755.26818@en.ecn.purdue.edu> irvine@en.ecn.purdue.edu (/dev/null) writes: #It not the Shuttle. Why Should it be the same? The problem is, and I know that I am being overly harsh on the shuttle on this, but Joe Congresscritter, or even Joe Average Public can just say: "You screwed up the last time, why should I trust you know?" and you say: "ALS is not the shuttle." then you lose. I don't have to prove that ALS won't work. You have to prove it will, at least before you expect to have large sums of money given to it. Since the track record so far is an expensive launch system that does not meet promises, it is nearly *impossible* to trust you again. You have to earn the trust of those who control the money. So far ALS has not. -- -Greg Hennessy, University of Virginia USPS Mail: Astronomy Department, Charlottesville, VA 22903-2475 USA Internet: gsh7w@virginia.edu UUCP: ...!uunet!virginia!gsh7w ------------------------------ Date: 28 Apr 91 23:55:16 GMT From: udecc.engr.udayton.edu!blackbird.afit.af.mil!tkelso@tut.cis.ohio-state.edu (TS Kelso) Subject: NASA Prediction Bulletins: Space Shuttle The most current orbital elements from the NASA Prediction Bulletins are carried on the Celestial BBS, (513) 427-0674, and are updated several times weekly. Documentation and tracking software are also available on this system. As a service to the satellite user community, the most current elements for the current shuttle mission are provided below. The Celestial BBS may be accessed 24 hours/day at 300, 1200, or 2400 baud using 8 data bits, 1 stop bit, no parity. STS 39 1 21242U 91 31 A 91118.60338562 .00193162 23739-4 25599-3 0 26 2 21242 56.9897 288.8514 0009153 256.9690 102.8903 16.06278845 20 -- Dr TS Kelso Assistant Professor of Space Operations tkelso@blackbird.afit.af.mil Air Force Institute of Technology ------------------------------ Date: 29 Apr 91 00:19:22 GMT From: udecc.engr.udayton.edu!blackbird.afit.af.mil!tkelso@tut.cis.ohio-state.edu (TS Kelso) Subject: NASA Prediction Bulletin Format As a service to the satellite user community, the following description of the NASA Prediction Bulletin's two-line orbital element set format is uploaded to sci.space on a monthly basis. The most current orbital elements from the NASA Prediction Bulletins are carried on the Celestial BBS, (513) 427-0674, and are updated several times weekly. Documentation and tracking software are also available on this system. The Celestial BBS may be accessed 24 hours/day at 300, 1200, or 2400 baud using 8 data bits, 1 stop bit, no parity. ============================================================================== Data for each satellite consists of three lines in the following format: AAAAAAAAAAA 1 NNNNNU NNNNNAAA NNNNN.NNNNNNNN +.NNNNNNNN +NNNNN-N +NNNNN-N N NNNNN 2 NNNNN NNN.NNNN NNN.NNNN NNNNNNN NNN.NNNN NNN.NNNN NN.NNNNNNNNNNNNNN Line 1 is a eleven-character name. Lines 2 and 3 are the standard Two-Line Orbital Element Set Format identical to that used by NASA and NORAD. The format description is: Line 2 Column Description 01-01 Line Number of Element Data 03-07 Satellite Number 10-11 International Designator (Last two digits of launch year) 12-14 International Designator (Launch number of the year) 15-17 International Designator (Piece of launch) 19-20 Epoch Year (Last two digits of year) 21-32 Epoch (Julian Day and fractional portion of the day) 34-43 First Time Derivative of the Mean Motion or Ballistic Coefficient (Depending on ephemeris type) 45-52 Second Time Derivative of Mean Motion (decimal point assumed; blank if N/A) 54-61 BSTAR drag term if GP4 general perturbation theory was used. Otherwise, radiation pressure coefficient. (Decimal point assumed) 63-63 Ephemeris type 65-68 Element number 69-69 Check Sum (Modulo 10) (Letters, blanks, periods = 0; minus sign = 1; plus sign = 2) Line 3 Column Description 01-01 Line Number of Element Data 03-07 Satellite Number 09-16 Inclination [Degrees] 18-25 Right Ascension of the Ascending Node [Degrees] 27-33 Eccentricity (decimal point assumed) 35-42 Argument of Perigee [Degrees] 44-51 Mean Anomaly [Degrees] 53-63 Mean Motion [Revs per day] 64-68 Revolution number at epoch [Revs] 69-69 Check Sum (Modulo 10) All other columns are blank or fixed. Example: NOAA 6 1 11416U 86 50.28438588 0.00000140 67960-4 0 5293 2 11416 98.5105 69.3305 0012788 63.2828 296.9658 14.24899292346978 Note that the International Designator fields are usually blank, as issued in the NASA Prediction Bulletins. -- Dr TS Kelso Assistant Professor of Space Operations tkelso@blackbird.afit.af.mil Air Force Institute of Technology ------------------------------ Date: 8 May 91 18:26:45 GMT From: snorkelwacker.mit.edu!hsdndev!frooz!cfashap!pinto@bloom-beacon.mit.edu (Philip Pinto) Subject: YOUR HELP NEEDED URGENTLY TO SAVE SPACE SCIENCE! ------------------------------ End of SPACE Digest V13 #524 *******************