Jonathan's Space Report No. 506 2003 Aug 13, Cambridge, MA ------------------------------------------------------------------------------- Shuttle and Station -------------------- The Expedition 7 crew, Yuriy Malenchenko and Edward Lu, remain on board the Space Station. The Space Shuttle fleet remains grounded. Errata ------- I should know better than to do physics in public. A couple of readers caught my goof in the foam calculation last issue: using the equations in the CAIB document, I foolishly did not account for the fact that for a denser material like ice, the lower drag acceleration means that the time to travel a fixed distance d in the orbiter rest frame is a function of the density. My correspondents assumed constant acceleration a and derived v^2 = 2ad which leads to a kinetic energy independent of density. (This isn't right either, since the acceleration decreases quite quickly as the the particle's velocity approaches the flow velocity, and if you integrate the velocity equation derived by the CAIB you get a more complicated formula, but to first order it is true that the the KE is independent of density, not inversely proportional as I claimed.) In fact, the KE for the ice impact is about 50 percent larger than that for the foam. Oh well, the point remains that foam is, counterintuitively, not as much better than ice as you might expect. Neville Kidger points out that he published the TMA-1 landing time in the July 2003 issue of Spaceflight. Fair enough Neville, you beat me :-) Recent Launches --------------- Orbital Sciences' L-1011 Stargazer carrier aircraft took off from Vandenberg AFB at 0113 UTC on Aug 13 carrying a Pegasus rocket, and headed out over the Pacific. At 0209 UTC, probably at the standard drop location of 36N 123W, the Pegasus was released at an altitude of about 12 km and ignited its first stage motor 5 seconds later. At 0217 UTC the third stage and its Scisat-1 payload reached a 641 x 654 km x 73.9 deg orbit. Scisat-1 is a scientific satellite for the Canadian Space Agency and carries the ACE-FTS spectrometer to study the chemistry of the upper troposphere and stratosphere, as well as the MAESTRO instrument to study ozone and aerosol levels in the atmosphere. The Russian Space Forces launched an 115A11U Soyuz-U rocket from area 31 at Baykonur on Aug 12. 9 minutes later the 11S510 Blok-I third stage entered a 170 x 311 km x 65.0 deg orbit and released a classified reconnaissance satellite which was given the cover name Kosmos-2399. This initial orbit is similar to the initial orbits of the Don spy satellites, a variant of the Yantar' series. The Don carries 8 recoverable film capsules and has a total mass of around 7600 kg. If Kosmos-2399 is a Don, it should change its orbit in a couple of days to an operational 210 x 311 km orbit and will probably remain in orbit for around 4 months. However, after I wrote the previous sentence and prepared to send this report out, Space Command released new orbital data showing Kosmos-2399 instead manoeuvred to a 172 x 356 km orbit more reminiscent of the Kobal't spy satellites. I doubt it's one of those, since there hasn't been a Kobal't launch from Baykonur since 1989 - the last 35 launches have been from Plesetsk. (Actually, the current low-perigee satellite is almost certainly a successor generation to Kobal't, but we don't know its classified name yet, so I'm sticking with the old name for now). But the new orbit does match the initial orbit for the third Don flight, Kosmos-2163. So I still think I'm right in guessing this is a Don flight, and I predict a new orbit raising burn within 24 hours will increase the perigee to around 210 km. Previous launches of Don satellites were: Launch date Duration Initial orbit Final orbit Don (1) Kosmos-2031 1989 Jul 18 59d 193x263x50.5 230x296x50.5 Don (2) Kosmos-2101 1990 Oct 1 60d 170x296x64.8 210x292x64.8 Don (3) Kosmos-2163 1991 Oct 9 59d 171x352x64.8 208x355x64.8 Don (4) Kosmos-2225 1992 Dec 22 58d 170x310x64.9 214x308x64.9 Don (5) Kosmos-2262 1993 Sep 7 103d 172x290x64.9 207x323x64.9 Don (6) Kosmos-2343 1997 May 15 126d 169x324x64.9 205x323x64.9 ? Kosmos-2399 2003 Aug 12 170x311x64.9 172x356x64.9 Recent Kobal't launches were: Kobal't (80) Kosmos-2365 1999 Aug 18 119d 166x342x67.1 166x341x67.1 Kobal't (81) Kosmos-2377 2001 May 29 103d 165x358x67.1 184x355x67.1 Kobal't (82) Kosmos-2387 2002 Feb 25 122d 165x344x67.1 185x357x67.1 Boeing Sea Launch put the Echostar 9 satellite in orbit on Aug 8. Echostar 9 carries a Ku and Ka band communications payload for Echostar, and a C-band payload currently owned by Loral Skynet but about to be sold to Intelsat. Loral calls the satellite Telstar 13. Mass of Echostar 9 was 4737 kg at launch; I don't know the dry mass. The Sea Launch Zenit-3SL put the payload first in a 180 x 913 km x 0 deg parking orbit and then, after a second burn and separation of the Blok DM-SL final stage, into a 713 x 35855 km x 0.03 deg geostationary transfer orbit. The inclination to the equator of only 0.03 deg is the lowest of any Sea Launch flight to date and I believe the lowest inclination initial orbit insertion ever. The Zenit-3SL rocket is launched from a floating platform directly on the equator. A small debris object, 1990-037D, has been tracked and been associated with the Hubble Space Telescope; I'm guessing a piece of insulation has flaked off. It was given catalog number 27822, previously expected to be assigned to the Briz-M rocket from the AMC-9 launch. The Briz-M has not yet been cataloged. Aalborg University has contacted its AAU-Cubesat nanosatellite. As far as I know, the other Danish cubesat DTUSat is still silent. A source tells me that the identifications in the Space Command for some of the 2003-031 objects are still mixed up. Table of Recent Launches ----------------------- Date UT Name Launch Vehicle Site Mission INTL. DES. Jul 8 0318 MER-B Opportunity Delta 7925H Canaveral SLC17B Mars probe 32A Jul 17 2345 Rainbow 1 Atlas V 521 Canaveral SLC41 Comms 33A Aug 8 0331 Echostar 9 Zenit-3SL Odyssey, POR Comms 34A Aug 12 1420 Kosmos-2399 Soyuz-U Baykonur LC31/6 Imaging 35A Aug 13 0209 Scisat-1 Pegasus XL Vandenberg RW30/12 Science 36A .-------------------------------------------------------------------------. | Jonathan McDowell | phone : (617) 495-7176 | | Harvard-Smithsonian Center for | | | Astrophysics | | | 60 Garden St, MS6 | | | Cambridge MA 02138 | inter : jcm@cfa.harvard.edu | | USA | jmcdowell@cfa.harvard.edu | | | | JSR: http://hea-www.harvard.edu/~jcm/space/jsr/jsr.html | | Back issues: http://hea-www.harvard.edu/~jcm/space/jsr/back | | Subscribe/unsub: mail majordomo@head-cfa.harvard.edu, (un)subscribe jsr | '-------------------------------------------------------------------------'