Return-path: X-Andrew-Authenticated-as: 7997;andrew.cmu.edu;Ted Anderson Received: from po5.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 ; Fri, 12 Oct 90 02:41:52 -0400 (EDT) Received: from beak.andrew.cmu.edu via qmail ID ; Fri, 12 Oct 90 02:41:16 -0400 (EDT) Message-ID: Precedence: junk Reply-To: space+@Andrew.CMU.EDU From: space-request+@Andrew.CMU.EDU To: space+@Andrew.CMU.EDU Date: Fri, 12 Oct 1990 02:38:52 -0400 (EDT) Subject: SPACE Digest V12 #449 SPACE Digest Volume 12 : Issue 449 Today's Topics: When is SALUT 7 going to fall? Voyager Update - 10/11/90 Re: Ulysses Update - 10/06/90 Clyde Tombaugh lecture Re: Ulysses Update - 10/06/90 N-waste sea water dilution Re: disposal of N-waste into sun Re: Frame sequential TV in space Orbital elements Magellan Update - 10/11/90 Re: Deep Space Network use (Was: Ulysses Update - 10/06/90) Space Books Administrivia: Submissions to the SPACE Digest/sci.space should be mailed to space+@andrew.cmu.edu. Other mail, esp. [un]subscription notices, should be sent to space-request+@andrew.cmu.edu, or, if urgent, to tm2b+@andrew.cmu.edu ---------------------------------------------------------------------- Date: 10 Oct 90 08:00:41 GMT From: mcsun!unido!mpirbn!p515dfi@uunet.uu.net (Daniel Fischer) Subject: When is SALUT 7 going to fall? November 1990 plus or minus two months: that was the date given in SPACE NEWS of 26 March for the reentry and crash of the old Soviet space station Salut 7. For months I haven't heard about that: what's the latest prediction? Did the falling solar activity give the Soviets a few more months? But even so: that the station should be in a stable orbit again is hard to believe. Any recent indications of a rescue mission or controlled reentry recently? As Salut has some 20 tons mass + another module attached, it seems we might be in for another Skylab-style adventure. Therefore it's strange so little is being heard about it, especially in the net ("Falling Salut - why not nuke it?" :-). p515dfi@mpifr-bonn.mpg.de <> Daniel Fischer ------------------------------ Date: 11 Oct 90 22:01:20 GMT From: usc!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov!baalke@ucsd.edu (Ron Baalke) Subject: Voyager Update - 10/11/90 Voyager Mission Status October 11, 1990 Voyager 1 The Voyager 1 spacecraft collected routine UVS (Ultraviolet Spectrometer) data on source HD 217675. There was a PWS (Plasma Wave ) high-rate record frame on October 1. On September 28, TWNC was turned off for 3-way ranging from the 70 meter antenna in Australia to the 70 meter antenna in Spain. On September 29 TWNC was turned back on. There was an tracking outage of 4 hours and 55 minutes with the 34 meter antenna in Spain on September 29 because of heavy rain. On October 3 real-time commands were transmitted to lock the PRA (Planetary Radio Astronomy) receiver; these commands were necessary due to the incomplete PRA recovery on September 26 which left the PRA receiver local oscillator loop unlocked. The PRA instrument response to the real-time commands was as predicted. Voyager 2 The Voyager 2 spacecraft collected routine UVS data on sources Markarian 509 and PKS2155-304. On October 2, one frame of high-rate PWS was recorded. There was an tracking outage of 4 hours and 45 minutes with the 34 meter antenna in Spain on September 28 because of heavy rain. CONSUMABLE STATUS AS OF 10/11/90 P R O P E L L A N T S T A T U S P O W E R Consumption One Week Propellant Remaining Output Margin Spacecraft (Gm) (Kg) Watts Watts Voyager 1 5 36.3 + 2.0 369 56 Voyager 2 5 39.4 + 2.0 370 62 ___ _____ ___ /_ /| /____/ \ /_ /| | | | | __ \ /| | | | Ron Baalke | baalke@mars.jpl.nasa.gov ___| | | | |__) |/ | | |___ Jet Propulsion Lab | baalke@jems.jpl.nasa.gov /___| | | | ___/ | |/__ /| M/S 301-355 | |_____|/ |_|/ |_____|/ Pasadena, CA 91109 | ------------------------------ Date: 11 Oct 90 13:19:55 GMT From: rochester!uhura.cc.rochester.edu!haake@rutgers.edu (Bill Haake) Subject: Re: Ulysses Update - 10/06/90 In article <3602@syma.sussex.ac.uk: andy@syma.sussex.ac.uk (Andy Clews) writes: :From article <1990Oct9.034919.25903@jato.jpl.nasa.gov>, by :baalke@mars.jpl.nasa.gov (Ron Baalke): :> The closest Ulysses will ever :> get to the sun in its lifetime is when it was on Earth. : :Shome mishtake, shurely? What about when Ulysses was in the orbiter payload :bay in orbit around Earth? Or even after deployment as it floated gently Not if we weren't at perihelion when it was in orbit! :-) -- Bill Haake haake@cvs.rochester.edu (128.151.80.13) University of Rochester (716) 275-8680 ------------------------------ Date: 11 Oct 90 13:27:11 GMT From: bbn.com!koolish@apple.com (Dick Koolish) Subject: Clyde Tombaugh lecture Clyde Tombaugh, discoverer of Pluto, will give a lecture at the Hayden Planetarium of the Boston Museum of Science on Thursday, October 18 at 8:00 PM. Admission is $10.00 with all proceeds going into a scholarship fund. For tickets, send a check payable to the Museum of Science and a self-addressed stamped envelope to: Tombaugh Lecture Hayden Planetarium Museum of Science Boston, MA 02114 ------------------------------ Date: 11 Oct 90 10:49:56 GMT From: usc!cs.utexas.edu!news-server.csri.toronto.edu!utgpu!watserv1!maytag!watcsc!death@ucsd.edu (Trevor Green) Subject: Re: Ulysses Update - 10/06/90 andy@syma.sussex.ac.uk (Andy Clews) writes: >baalke@mars.jpl.nasa.gov (Ron Baalke): >> The closest Ulysses will ever >> get to the sun in its lifetime is when it was on Earth. > >Shome mishtake, shurely? What about when Ulysses was in the orbiter payload >bay in orbit around Earth? Or even after deployment as it floated gently >away from Discovery, on the side of the Earth facing the sun and before its >boosters were fired to send it off on its merry way? > >I mean c'mon guys, let's have some accuracy here! :-) :-) Okee dokee. The closest Ulysses will have ever gotten to the sun was some time in early January, one of the past few years, within 12 hours of Earth's perihelion. We are currently at least some few hundreds of thousands, if not millions, of kilometres shy of that point currently - a deficit which LEO is at a loss to make up. Happy to inject some actual accuracy into the discussion, (-: Trevor Green ------------------------------ Date: 10 Oct 90 18:00:30 GMT From: ubc-cs!cpsc.ucalgary.ca!news@beaver.cs.washington.edu (Michael Hermann) Subject: N-waste sea water dilution In article <1452@blenheim.nsc.com> alan@spitfire.nsc.com (Alan Hepburn) writes: >Picture this: a supertanker modified slightly so that the nuclear >waste starts out in the bow tank, being diluted 100:1 with sea water. >This mix is then pumped to the next tank where it is diluted 100:1 with >sea water. And so on till the last tank, which is pumped into the open >ocean. You would be unable to detect other than background radiation >in the resulting water. Gee, that's such a good idea. We could even do the same thing on land. Perhaps in the desert. Or normal garbage headed for the landfill. I'm sure Mr. Hepburn wouldn't mind us using his local landfill site. Afterall, one backyard is as good as another. I hope you were joking. | Mike Hermann | hermann@cpsc.ucalgary.ca ..!uunet!ubc-cs!calgary!hermann _Organized_ religion is like organized crime: it preys on peoples' weaknesses, generates huge profits, and is nearly impossible to eradicate. -- | Mike Hermann | hermann@cpsc.ucalgary.ca ..!uunet!ubc-cs!calgary!hermann _Organized_ religion is like organized crime: it preys on peoples' weaknesses, generates huge profits, and is nearly impossible to eradicate. ------------------------------ Date: 11 Oct 90 17:58:56 GMT From: usc!wuarchive!cs.utexas.edu!news-server.csri.toronto.edu!helios.physics.utoronto.ca!physics.utoronto.ca!neufeld@ucsd.edu (Christopher Neufeld) Subject: Re: disposal of N-waste into sun In article <106611@convex.convex.com> dodson@convex.COM (Dave Dodson) writes: >In article <1990Sep26.155912.4515@zoo.toronto.edu> henry@zoo.toronto.edu (Henry Spencer) writes: >>In article <1990Sep25.184737.15418@unicorn.wwu.edu> n9020351@unicorn.wwu.edu (james d. Del Vecchio) writes: >>>Why would it be harder to send something to the sun than away from the sun? >> >>The direction is unimportant; what matters is the velocity change needed. >>To get something into the Sun, you have to kill *all* of Earth's orbital >>velocity (well, just about), and that's 30 km/s, a horrendous amount for >>chemical rockets. > >Time for a little arithmetic here. Let's use the following approximate >values for these constants: > >Earth's Surface Escape Velocity 11 km/sec >Earth's Orbital Velocity around Sun 30 km/sec > >A launch into the sun requires sqrt (11^2 + 30^2) km/sec =~ 32 km/sec. >This is so the payload, after having climbed out of the Earth's gravity >well, is travelling away from the Earth at 30 km/sec. If the velocity >vector is in the opposite direction from the Earth's velocity vector >around the sun, the payload would fall into the sun. > This is wrong. If something is fired away from the surface of the Earth at Earth escape velocity of ~11 km/s, it will wind up pacing the Earth in its orbit around the Sun at 30 km/s. This is regardless of the direction in which the object is fired away from the surface. You still need another 30 km/s to fall into the Sun. This makes a total of 41 km/s, not 32 km/s. I don't understand why you felt you needed the Pythagorean identity here. Recall from first-year physics classes that the "escape velocity" is in fact a scalar, and that neglecting atmospheric effects, any object fired in any trajectory which does not intersect the ground or a mountain or something, will leave if fired in excess of 11 km/s. >A launch to solar escape requires sqrt (11^2 + (30^2)/2) km/sec =~ 24 km/sec. >This is so the payload, after climbing out of the Earth's gravity well, is >travelling away from the Earth at 30(sqrt(2)-1) km/sec =~ 12.5 km/sec. If >the velocity vector is in the same direction as the Earth's, the payload would >have solar escape velocity and depart the solar system. > Again wrong, for the same reason. It takes 11 km/s + 1/sqrt(2) * 30 km/s, or roughly 23 km/s. >Thus solar impact requires 32/24 = 4/3 as much energy as solar escape. > No, roughly 7/4. >All of these energy requirements could be reduced by using gravity assist >flybys of various planets, but would you want to jeopardize contaminating a >planet with radioactive debris in case of a navigation error or onboard >failure? > No, so we'd better all get out there and put motors and navigation equipment on every asteroid in the solar system. They may not have a very high density of radioactive material, but they weigh billions of times more than any earthly probe would. Oh, but natural radioactivity is harmless, isn't it? >Dave Dodson dodson@convex.COM >Convex Computer Corporation Richardson, Texas (214) 497-4234 -- Christopher Neufeld....Just a graduate student | "The pizza was just a neufeld@helios.physics.utoronto.ca Ad astra! | detonator; I mean, if cneufeld@{pnet91,pro-micol}.cts.com | it had set off the "Don't edit reality for the sake of simplicity" | hams...." Downtown Brown ------------------------------ Date: 9 Oct 90 23:18:34 GMT From: swrinde!zaphod.mps.ohio-state.edu!samsung!emory!emcard!wa4mei!ke4zv!gary@ucsd.edu (Gary Coffman) Subject: Re: Frame sequential TV in space In article <1048@sun13.scri.fsu.edu> pepke@gw.scri.fsu.edu (Eric Pepke) writes: >I saw some TV pictures from the Shuttle on CNN last night, and when there >was much motion, the image left behind colored ghost images. This leads >me to believe that it is essentially a frame-sequential system. > >If so, why is such a system used? I know that NTSC is notoriously phase >sensitive, but surely in this digital age we don't need to be limited by >that. Are the reasons historical? It's more likely that they are using old technology single tube cameras that suffer from color lag under modest (ie: not full sun) lighting. Newer cameras are not as bad about this, but NASA probably hasn't updated the cameras due to the paperwork involved in rating anything for space use on the shuttle. The newest cameras use chip pickups instead of tubes and suffer practically no lag. Gary ------------------------------ Date: 12 Oct 90 00:11:00 GMT From: lcsmith%mpx0.lampf.lanl.gov@lanl.gov (Smith, Lee C.) Subject: Orbital elements Does anyone know what happened to Kelso's orbital elements posts? Haven't seem them in weeks. They would be particularly useful in helping to track Salyut 7's impending reentry. ------------------------------ Date: 11 Oct 90 17:55:25 GMT From: usc!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov!baalke@ucsd.edu (Ron Baalke) Subject: Magellan Update - 10/11/90 Magellan Status Report October 11, 1990 The Magellan spacecraft has now completed 192 mapping orbits of Venus since the start of radar mapping operations on September 15. Good radar data from at least 188 orbits has been received. Six of the seven star calibrations in the past 24 hours were successful with attitude updates of about 6/100 of a degree. The foreground filter rejected one star on the unsuccessful star calibrations. The two desaturations were nominal. An increasing difference has been noted between the AACS (Attitude and Articulation Control Subsystem) commanded position of the solar panels and the position indicated by the potentiometers. If allowed to continue, the Solar Array Drive Mechanism (SADM) control loss fault protection could be triggered and a swap of the IODA (Input-Output Drive Assembly) could be attempted. While the cause is being investigated, a near-term fix of disabling the SADM control loss fault protection was approved and commanded yesterday. The next step is to readjust the software stops, reset the commanded position to match the actual position, and renable the SADM control loss fault protection. These corrections are expected to be completed by tomorrow. Commands to update the RAM and ROM safing reference parameters will be uploaded today. Radar engineering telemetry analysis and the production of a test image swath from orbit 553 shows that the radar sensor continue to operate normally. Prodution of standard image products throught the SAR (Synthetic Aperture Radar) processor continues. Eleven image swaths were successfully completed yesterday. ___ _____ ___ /_ /| /____/ \ /_ /| | | | | __ \ /| | | | Ron Baalke | baalke@mars.jpl.nasa.gov ___| | | | |__) |/ | | |___ Jet Propulsion Lab | baalke@jems.jpl.nasa.gov /___| | | | ___/ | |/__ /| M/S 301-355 | |_____|/ |_|/ |_____|/ Pasadena, CA 91109 | ------------------------------ Date: 11 Oct 90 18:33:12 GMT From: usc!wuarchive!cs.utexas.edu!news-server.csri.toronto.edu!utgpu!cunews!bnrgate!bwdlh131!mleech@ucsd.edu (Marcus Leech) Subject: Re: Deep Space Network use (Was: Ulysses Update - 10/06/90) In article <10045@xenna.Xylogics.COM>, barnes@Xylogics.COM (Jim Barnes) writes: > In article <1990Oct7.050758.4684@jato.jpl.nasa.gov> baalke@mars.jpl.nasa.gov (Ron Baalke) writes: > > > If Ulysses needs 8 hours per day of coverage, Magellan is returning radar > images several times a day, and Galileo is doing some interesting things > at the same time, are there enough minutes in the day? Will we just > ignore the Voyagers/Pioneers/etc. for a while? How much extra bandwidth > does the DSN have? The **rumour** I have heard is that NASA is trying to get enough funding to take over the 46M dish at the Algonquin Radio Observatory as an additional site for DSN work. I'm not able to verify this, so treat is as a rumour. ----------------- Marcus Leech, 4Y11 Bell-Northern Research |opinions expressed mleech@bnr.ca P.O. Box 3511, Stn. C |are my own, and not VE3MDL@VE3JF.ON.CAN.NA Ottawa, ON, CANADA |necessarily BNRs ------------------------------ Date: 11 Oct 90 12:11:33 GMT From: bacchus.pa.dec.com!shlump.nac.dec.com!imokay.Berkeley.EDU!borsom@decwrl.dec.com (Doug Borsom) Subject: Space Books A couple months back, someone posted a note about Wernher von Braun's book "The Mars Project." (A great book, as the poster pointed out.) A follow-up posting mentioned that the book might be available from a San Diego bookstore, Crawford-Peters Aeronautica, that specializes in aviation and space books. I would like to further recommend Crawford-Peters Aeronautica as an excellent source of all kinds of space publications. They publish a number of catalogs (they sell for a few bucks each) of their holdings, including, -Aviation and Space, 1945-1962 -Aviation and Space, 1962-1990 -Space and Related Titles Titles in the catalog "Space and Related Titles" include publications from the aerospace industry that appear to be the equivalent of the model descriptions and spec sheets you get at your local car dealer. In a phrase, the catalog offers lots of good stuff. I have found Crawford-Peters pleasant and honest to deal with. Crawford-Peters Aeronautica P.O. Box 152528 San Diego, CA 92115 (619) 287-3933 If there are specific books you're trying to find, give them a call. For those interested in spaceflight, the catalogs make fun browsing all on their own. My only connection with these folks is that of a satisfied customer. ------------------------------ End of SPACE Digest V12 #449 *******************