Date: Tue, 1 Sep 92 04:59:58 From: Space Digest maintainer Reply-To: Space-request@isu.isunet.edu Subject: Space Digest V15 #153 To: Space Digest Readers Precedence: bulk Space Digest Tue, 1 Sep 92 Volume 15 : Issue 153 Today's Topics: DCX?? Fireball over The Netherlands Wasn't (4 msgs) HST Update - 08/31/92 Shuttle seen from air UARS Update - 08/31/92 Upload Astronomy Lab for MS Win 3.x Venus orbiters What happened to Viking? What is the speed of light measured from? (4 msgs) 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: 31 Aug 92 09:59:23 GMT From: Patrick Chester Subject: DCX?? Newsgroups: sci.space > | Allen W. Sherzer | "If they can put a man on the Moon, why can't they | >| aws@iti.org | put a man on the Moon?" | >+----------------------238 DAYS TO FIRST FLIGHT OF DCX----------------------+ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^??? Pardon me for seeming clueless, but what is the dcx? Thank you. Patrick Chester ------------------------------ Date: Mon, 31 Aug 1992 07:42:08 GMT From: Harm Munk Subject: Fireball over The Netherlands Wasn't Newsgroups: sci.space,sci.astro On wednesday, August 19, seismic stations located in the northwestern part of the Netherlands registered an atmospheric shock wave, which, apparantly, was not related to any seismic activity. In the following days, the Royal Dutch Meteorological Institute (KNMI) in the Netherlands investigated the matter and came to the conclusion that it had probably been a meteor with a cross section of 30 cm which had exploded over the town of Joure in Friesland (a Dutch province). [See previous postings on Fireball over NW Europe] Later investigations by the KNMI and a group of astronomers showed that the only possible explanation left is not a meteorite or space junk, but some kind of supersonic, military airplane breaking the sound barrier some ten miles west of the island of Texel. According to the KNMI, this is the only explanation left allthough it is an unsatisfactory one. Because it supposedly was a military airplane, the KNMI contacted the military airbase Aurora in Scotland, but the spokesperson at Aurora did not know of any observation of a supersonic, military aircraft that evening. So, what was it? Rumours in the newspapers suggested that it was that highly secretive airplane that Lockeed is developing for the DoD: the two stage get to orbit plane (like DynaSoar and Saenger ?). Now, this plane has been sighted in the US a few times. The supposed sighting in the Netherlands was accompanied not only by sonic booms (energetic enough to crack the front of a house somewhere in the province of Friesland) but some people reported seeing a flash of light as well. Was this also the case with the sightings in the US? And why would the DoD start testing a secret plane outside US territory? And why was someone from Lockeed Space and Missiles Systems asking questions on the net about this event (;-)? +----------------------------------------+------------------------------------+ | Harm Munk | Building WAY 11 | | Philips Research Laboratories | P.O. Box 80 000 | | Knowledge Based Systems | 5600 JA Eindhoven | | | The Netherlands | | #include | tel. +31 40 74 46 59 | | | email: munk@prl.philips.nl | +----------------------------------------+------------------------------------+ ------------------------------ Date: Mon, 31 Aug 1992 13:36:51 GMT From: Gerald Cecil Subject: Fireball over The Netherlands Wasn't Newsgroups: sci.space,sci.astro In article 715246928@prles6b, munk@prl.philips.nl (Harm Munk) writes: >On wednesday, August 19, seismic stations located in the northwestern part >of the Netherlands registered an atmospheric shock wave, which, apparantly, >was not related to any seismic activity .. but some kind >of supersonic, military airplane breaking the sound barrier some ten miles west >of the island of Texel. According to the KNMI, this is the only explanation left >allthough it is an unsatisfactory one. ... >The supposed sighting in the Netherlands was accompanied not only by sonic >booms (energetic enough to crack the front of a house somewhere in the province of >Friesland) but some people reported seeing a flash of light as well. Was this >also the case with the sightings in the US? They probably saw a low-flying military aircraft with its afterburners on. Maybe it punched through a low-lying cloud deck on its way out. >Rumours in the newspapers suggested that it was that highly >secretive airplane that Lockeed is developing for the DoD: the two stage get >to orbit plane (like DynaSoar and Saenger ?). Now, this plane has been sighted >in the US a few times. ... According to Aviation Week & Space Technology (aka AvLeak) in issues prior to Aug. 24, this aircraft is an SR 71 replacement developed by Lockheed Skunkworks. Speeds estimated at 3500+ mph. *Not* a 2 stage to orbit plane. It has only been seen near the ground dimly at night, and was described as `bat-like'' similar to the B2 airfoil. People report a low frequency, growling noise of tremendous power at takeoff. Daytime photos of peculiar corkscrew contrails that have been attributed to this aircraft suggest an ``explosive'' or pulsed propulsion system, but the observers did not have binoculars to see the plane itself (flying at high altitudes). AvLeak reports an increasing number of daytime sightings like this, suggesting that the program is emerging from the so-called Black (i.e. non-itemized) DoD budget into full Congressional scrutiny, presumably because the DoD has now sunk so much money into it and distributed its contractors into so many Congressional districts that the program is unkillable. Yet another multi-billion dollar aerospace program to protect US airspace from the Bosnian airforce. >And why was someone from Lockeed Space and Missiles Systems asking questions >on the net about this event (;-)? S/he was probably searching for a new job. --- Gerald Cecil cecil@wrath.physics.unc.edu 919-962-7169 Physics & Astronomy, U of North Carolina, Chapel Hill, NC 27599-3255 USA ------------------------------ Date: 31 Aug 92 15:59:44 +0100 From: Alan Greig Subject: Fireball over The Netherlands Wasn't Newsgroups: sci.space,sci.astro In article , munk@prl.philips.nl (Harm Munk) writes: > > Because it supposedly was a military airplane, the KNMI contacted the military > airbase Aurora in Scotland, but the spokesperson at Aurora did not know > of any observation of a supersonic, military aircraft that evening. Can't say I've ever heard of a military airbase called Aurora in Scotland. Sounds a very unlikely name for an RAF base in any case. -- Alan Greig Janet: Alan@UK.AC.DUNDEE-TECH Dundee Institute of Technology Tel: (0382) 308810 Scotland, UK ------------------------------ Date: Mon, 31 Aug 1992 18:10:33 GMT From: dearnsha@wizard.worldbank.org Subject: Fireball over The Netherlands Wasn't Newsgroups: sci.space In article <1992Aug31.155944.272@dct.ac.uk> ccdarg@dct.ac.uk (Alan Greig) writes: >In article , munk@prl.philips.nl (Harm Munk) writes: >> >> Because it supposedly was a military airplane, the KNMI contacted the military >> airbase Aurora in Scotland, but the spokesperson at Aurora did not know >> of any observation of a supersonic, military aircraft that evening. > >Can't say I've ever heard of a military airbase called Aurora in Scotland. >Sounds a very unlikely name for an RAF base in any case. >-- > >Alan Greig Janet: Alan@UK.AC.DUNDEE-TECH >Dundee Institute of Technology Tel: (0382) 308810 >Scotland, UK > Aurora isn't an RAF base, it's the code name for a SR71 replacement. It would appear (according to sc.military) that the new plane operates out of a test facility out west (a'la U2/SR71), and uses Machrihanish base in the U.K. as it's European base. More information on this can be found on the sc.military newsgroup - although the information is (understandbly) sparse and subject to interperatation. ------------------------------ Date: Tue, 1 Sep 1992 06:01:01 GMT From: Ron Baalke Subject: HST Update - 08/31/92 Newsgroups: sci.space,sci.astro Forwarded from the SpaceLink BBS HUBBLE STATUS REPORT August 31, 1992 HUBBLE SPACE TELESCOPE (HST): HST operations have returned to normal following the recent safehold entry and recovery. Starting on July 30, a chain of events caused HST first to enter an inertial hold safemode followed by a hardware sunpoint safemode. The first was caused by an incorrect ephemeris table that was loaded into the spacecraft computer, and the latter by a problem with an onboard computer software macro. Science observations that were scheduled for execution during the safemode events are being rescheduled. HST launched April 24, 1990 aboard the Space Shuttle Discovery. ___ _____ ___ /_ /| /____/ \ /_ /| Ron Baalke | baalke@kelvin.jpl.nasa.gov | | | | __ \ /| | | | Jet Propulsion Lab | ___| | | | |__) |/ | | |__ M/S 525-3684 Telos | Anything is impossible if /___| | | | ___/ | |/__ /| Pasadena, CA 91109 | you don't attempt it. |_____|/ |_|/ |_____|/ | ------------------------------ Date: 1 Sep 92 04:32:36 GMT From: John Roberts Subject: Shuttle seen from air Newsgroups: sci.space -From: henry@zoo.toronto.edu (Henry Spencer) -Subject: Re: Need GIF (JPG, whatever) of Shuttle Landing -Date: 26 Aug 92 18:44:05 GMT -In article <26AUG199212415150@lims01.lerc.nasa.gov> afwendy@lims01.lerc.nasa.gov (WENDY WARTNICK) writes: ->wouldn't it be cool if NASA or the Air Force or someone would send up some ->sort of high altitude/space chase plane for cool space shots... -I've seen a photo of a shuttle launch seen from the air, from the Shuttle -training aircraft I think. NASA Select occasionally replays Shuttle launches as seen from the air (helicopters?), and sometimes video shot out the side of the Shuttle (ground dropping away). Of course, video doesn't generally make great still pictures. John Roberts roberts@cmr.ncsl.nist.gov ------------------------------ Date: Tue, 1 Sep 1992 06:03:06 GMT From: Ron Baalke Subject: UARS Update - 08/31/92 Newsgroups: sci.space,sci.astro Forwarded from the SpaceLink BBS UARS STATUS REPORT August 31, 1992 UPPER ATMOSPHERE RESEARCH SATELLITE (UARS): Attempts to restart the Improved Stratospheric and Mesospheric Sounder (ISAMS) chopper wheel motor have not been successful. The motor stopped working on July 29. The chopper wheel breaks up or "chops" the incoming light beam for analysis. Automated attempts to restart the chopper motor continue. ISAMS measures ozone, nitrogen compounds and other gasses important in ozone depletion. Most of these compounds are measured by other UARS instruments, so the loss of ISAMS has minimal impact on the UARS science mission at this time. UARS launched September 12, 1991 from the Space Shuttle Discovery. ___ _____ ___ /_ /| /____/ \ /_ /| Ron Baalke | baalke@kelvin.jpl.nasa.gov | | | | __ \ /| | | | Jet Propulsion Lab | ___| | | | |__) |/ | | |__ M/S 525-3684 Telos | Anything is impossible if /___| | | | ___/ | |/__ /| Pasadena, CA 91109 | you don't attempt it. |_____|/ |_|/ |_____|/ | ------------------------------ Date: 31 Aug 92 14:36:40 GMT From: Eric Bergman-Terrell Subject: Upload Astronomy Lab for MS Win 3.x Newsgroups: comp.windows.ms.programmer,comp.windows.ms.misc,comp.ibm.pc.misc,comp.os.ms-windows.apps,sci.space,sci.astro,sci.edu If you are willing to upload Astronomy Lab version 1.13 to an ftp site or bbs, I'd like to e-mail you a uuencoded .zip file of the program. You must be able to handle a ~500k e-mail message containing the uuencoded program. After uploading the program, please send me instructions on how users can upload the program. ... Astronomy Lab is an astronomy program for MS Windows 3.X. Astronomy Lab produces 7 movies that simulate a host of astronomical phenomena, 15 graphs that illustrate many fundamental concepts of astronomy, and 14 reports that predict the most important astronomical events. All movies, graphs, and reports are customized for the user's time zone and location. The entire User's Guide is available as on-line help. This is version 1.13. ------------------------------ Date: 1 Sep 92 04:37:54 GMT From: John Roberts Subject: Venus orbiters Newsgroups: sci.space -From: baalke@kelvin.jpl.nasa.gov (Ron Baalke) -Subject: Re: Venus orbiters -Date: 26 Aug 92 07:07:16 GMT -Organization: Jet Propulsion Laboratory -In article , rabjab@golem.ucsd.edu (Jeff Bytof) writes... ->Is the Pioneer Venus orbiter still functioning? -Yup, but it is running out of propellent and is due to burn up in the -atmosphere of Venus this December. Will the trajectory of Pioneer Venus as it burns up provide useful information for the planning of the Magellan aerobraking experiment? (Density and drag at various altitudes, etc.) John Roberts roberts@cmr.ncsl.nist.gov ------------------------------ Date: 1 Sep 92 04:58:54 GMT From: John Roberts Subject: What happened to Viking? Newsgroups: sci.space -From: eugene@wilbur.nas.nasa.gov (Eugene N. Miya) -Subject: Re: What happened to Viking? -Date: 21 Aug 92 22:27:39 GMT -Organization: NAS, NASA Ames Research Center, Moffett Field, CA -In article <1992Aug20.233734.691@ringer.cs.utsa.edu> -burris@ennex1.eng.utsa.edu (John Burris) writes: ->I heard through the grapevine that someone sent a bogus signal to it which ->turned the antenna away from Earth, resulting in LOS. -That was Voyager II (briefly). The way I heard it was that the last lander still running was given a command that effectively translated as "point antenna at ground and wait for next command from Earth". Since then, NASA's gotten considerably better at the use of safe modes and watchdog timers. (For instance, Magellan might have only 1% coverage rather than 97% without such protection.) John Roberts roberts@cmr.ncsl.nist.gov ------------------------------ Date: Mon, 31 Aug 1992 13:36:21 GMT From: "Robert B. Whitehurst" Subject: What is the speed of light measured from? Newsgroups: sci.space In article <1992Aug30.130555.7676@spuddy.uucp> spark@spuddy.uucp (Steve) writes: > >OK. Someone can perhaps clear this little nagging thought in my head. > >I haven't done any relativity, or any complicated physics, so please >keep it simple. > ...[asks about invariance of speed of light] >Where is the speed of light measured relative to? > >Steve > Steve, As other posts in answer discuss, the speed of light (in a given media) is invariant. However, its direction of travel and source speed relative to the observer DOES affect its frequency. I'm sure you have heard sirens rise and fall in pitch as they approach and leave you. That is the Doppler effect, and light does the same. The light is blue- or red-shifted if the source and you are approaching or leaving each other. Astronauts traveling very near light speed would see a very strange star field, with the stars in front shining blue (or even UV, or X-ray if you are fast enough) and the ones behind showing red. Weird stuff indeed! -- Brad Whitehurst | Aerospace Research Lab rbw3q@Virginia.EDU | We like it hot...and fast. ------------------------------ Date: Mon, 31 Aug 1992 17:34:11 GMT From: "robert.f.casey" Subject: What is the speed of light measured from? Newsgroups: sci.space Makes you wonder how the "particle" of light "knows" how fast or slow to speed up by to be travelling at the -speed o' light- at or near the local frame of reference. Does it "feel" the local gravity, or something? ------------------------------ Date: 31 Aug 92 18:38:49 GMT From: "Frederick A. Ringwald" Subject: What is the speed of light measured from? Newsgroups: sci.space In article <1992Aug31.173411.13396@cbfsb.cb.att.com> wa2ise@cbnewsb.cb.att.com (robert.f.casey) writes: > Makes you wonder how the "particle" of light "knows" how fast or slow to > speed up by to be travelling at the -speed o' light- at or near the > local frame of reference. A particle of light (a photon) always travels the SAME speed, in a vacuum, relative to all observers. It doesn't have to know anything. It's the structure of space and time that changes: it's described at length in any special relativity text, such as Spacetime Physics by Taylor & Wheeler. > Does it "feel" the local gravity, or something? YES - the gravitational deflection of starlight was one of the major tests of general relativity, the one that made Einstein a household name. A good introductory text on general relativity is Gravitation & Spacetime, by Hans O'Hanian, although GR is not a field for the faint of heart or mathematically disinclined. Pity, too, since if you happen to already be a differential geometer, the physical theory is stunningly simple and beautiful: a typical course will spend about half the term developing math, two or three days discussing the theory, and the rest of the term talking about applications (neutron stars, black holes, post-Keplerian celestial mechanics as in the orbit of Mercury, etc.). ------------------------------ Date: 31 Aug 92 19:22:31 GMT From: "Frederick A. Ringwald" Subject: What is the speed of light measured from? Newsgroups: sci.space In article <1992Aug31.173411.13396@cbfsb.cb.att.com> wa2ise@cbnewsb.cb.att.com (robert.f.casey) writes: > Makes you wonder how the "particle" of light "knows" how fast or slow to > speed up by to be travelling at the -speed o' light- at or near the > local frame of reference. A particle of light (a photon) always travels the SAME speed, in a vacuum, relative to all observers. It doesn't have to know anything. It's the structure of space and time that changes: it's described at length in any special relativity text, such as Spacetime Physics by Taylor & Wheeler. > Does it "feel" the local gravity, or something? YES - the gravitational deflection of starlight was one of the major tests of general relativity, the one that made Einstein a household name. A good introductory text on general relativity is Gravitation & Spacetime, by Hans O'Hanian, although GR is not a field for the faint of heart or mathematically disinclined. Pity, too, since if you happen to already be a differential geometer, the physical theory is stunningly simple and beautiful: a typical course will spend about half the term developing math, two or three days discussing the theory, and the rest of the term talking about applications (neutron stars, black holes, post-Newtonian celestial mechanics as in the orbit of Mercury, etc.). ------------------------------ End of Space Digest Volume 15 : Issue 153 ------------------------------