Jonathan's Space Report No. 279 1996 Mar 11 Cambridge, MA -------------------------------------------------------------------------------- Shuttle ------- Columbia landed at 1358:21 UTC on runway 33 at Kennedy Space Center, bringing mission STS-75 to a close. Landing was delayed one day because of bad weather at the Cape. The Tethered Satellite was in a 296 x 360 km x 28.5 deg orbit on Mar 11, still trailing its 19 km long tether. (The 22 km figure I gave last week was an error). NASA has announced that both of the `wiper' O-rings at the case-to-nozzle joints of the SRBs on STS-75 were scorched by hot gas. The wiper O-rings are NOT joint seals, but merely protect the actual (primary and secondary) O-ring seals during assembly, according to NASA. Wiper O-ring damage has been seen before, but this time each O-ring was singed in two places instead of one. (Details are from Reuter; this doesn't sound too terrible, but of course hot gas being where it shouldn't in an SRB is a bit nervous making.) NASA has reportedly since decided that the situation is well understood and the next mission, STS-76, will proceed on schedule. It will feature another docking with the Mir space station. Recent Launches --------------- The Pegasus XL launch vehicle has made its first successful flight. The US Air Force REX-II satellite was launched into orbit aboard the third XL on Mar 9. REX-II is a Space Test Program satellite (flight P94-2) built by CTA/SS (formerly DSI). The payload, sponsored by USAF Rome Lab, will study ionospheric electron density irregularities that affect radio communications. A secondary experiment will use GPS for on-orbit attitude determination and control, a milestone in the integration of satellite navigation techniques into the business of navigating and controlling satellites themselves. The successful launch of REX-II is good news for Orbital Sciences Corp. and for all small satellite missions which are waiting for a ride to orbit, following the failures of the two previous Pegasus XL missions as well as of the sole Conestoga and LLV launches. The L-1011 carrier aircraft took off from Vandenberg AFB at 0035 UTC on Mar 9 and went to the drop zone 100 km W of Monterey, California at an altitude of 12 km. Drop was at 0133 UTC on Mar 9. The satellite is Space Command number 23814 with orbit 101.25 min, 803 x 832 km x 90.0 deg. The USAF reports that the satellite is operating well. Chinese sources now report that six people died and 57 were injured during the crash of the Chang Zheng 3B (Long March 3B) launch vehicle at Xichang on Feb 14. Other sources claim that more than a hundred may have died. The rocket's inertial guidance unit failed two seconds after takeoff. NASA's GGS Polar satellite has raised its perigee, but Space Command hasn't released new orbital elements yet. According to the Lockheed Martin mission ops page, the new orbit has a perigee of 11500 km. Orbit raising burns were made on Feb 26, 0200 UTC on Feb 28, 1854 on Feb 28, 1140 on Feb 29 and 0436 UTC on Mar 1. The first Feb 28 burn was aborted after 18 minutes due to valve overheating, causing some of the later burns to be rescheduled. Polar has extended its antennae: the U wires were deployed to 65 meters and the V wires to 50 meters on Mar 10. Table of Recent Launches ------------------------ Date UT Name Launch Vehicle Site Mission INTL. DES. Feb 1 0115 Palapa C-1 Atlas IIAS Canaveral LC36B Comsat 06A Feb 5 0719 N-STAR b Ariane 44P Kourou ELA2 Comsat 07A Feb 14 1901 Intelsat 708 Chang Zheng 3B Xichang Comsat FTO Feb 17 2043 NEAR Delta 7925-8 Canaveral LC17B Space probe 08A Feb 19 0058 Gonets-D1 ) 09A? Gonets-D1 ) 09B? Gonets-D1 ) Tsiklon-3 Plesetsk LC32 Comsats 09C? Kosmos-2328) 09D? Kosmos-2329) 09E? Kosmos-2330) 09F? Feb 19 0832 Raduga Proton-K/DM2 Baykonur LC81 Comsat 10A Feb 21 1234 Soyuz TM-23 Soyuz-U2 Baykonur LC1 Spaceship 11A Feb 22 2018 Columbia Shuttle Kennedy LC39B Spaceship 12A Feb 24 1124 Polar Delta Vandenberg SLC2W Science 13A Feb 26 0130 TSS-1 OV-102,LEO Science 12B Mar 9 0133 REX-II Pegasus XL L1011/Vandenberg Technol. 14A Payloads no longer in orbit -------------------------- Feb 22 Progress M-30 Deorbited over Pacific Feb 29 Soyuz TM-22 Landed in Kazakhstan Mar 9 Columbia Landed at KSC Current Shuttle Processing Status ____________________________________________ Orbiters Location Mission Launch Due OV-102 Columbia OPF Bay 2 STS-78 Jun 27 OV-103 Discovery Palmdale OMDP OV-104 Atlantis LC39B STS-76 Mar 21 OV-105 Endeavour OPF Bay 3 STS-77 May 16 ML/SRB/ET/OV stacks ML1/RSRM-54/ VAB Bay 1 STS-77 ML2/RSRM-46/ET-77/OV-104 LC39B STS-76 ML3/ .-------------------------------------------------------------------------. | Jonathan McDowell | phone : (617) 495-7176 | | Harvard-Smithsonian Center for | | | Astrophysics | | | 60 Garden St, MS6 | | | Cambridge MA 02138 | inter : jcm@urania.harvard.edu | | USA | jmcdowell@cfa.harvard.edu | | | | JSR: http://hea-www.harvard.edu/QEDT/jcm/space/jsr/jsr.html | | ftp://sao-ftp.harvard.edu/pub/jcm/space/news/news.* | '-------------------------------------------------------------------------'