Jonathan's Space Report No. 649 2011 Oct 25 Somerville, MA, USA -------------------------------------------------------------------------------- ROSAT reentry -------------- ROSAT reentered between 0143 and 0157 UTC on Oct 23 according to data from USSTRATCOM. Including the final orbital data released later on Oct 23, the uncertainty range covers the Indian Ocean, the Andaman Sea, Myanmar, Laos and China. There have been no confirmed sightings of the reentry. Germany's ROSAT satellite (Rongtensatellit) was the third X-ray mission to image the extrasolar X-ray sky, following Einstein and Exosat. It made the first imaging all-sky survey; its telescope observed at lower energy (`softer', longer wavelengths) than Chandra and XMM and so it was particularly sensitive to the (relatively) lower temperature nearby interstellar gas. It discovered X-rays from comets interacting with the solar wind, cataloged high redshift X-ray galaxy clusters and measured their dark matter, and identified many new quasars. The ROSAT X-ray telescope (XRT) and its main cameras, the two PSPC (Position Sensitive Proportional Counter), PSPC-B and PSPC-C, were developed under the leadership of the Max-Planck-Institut fur extraterrestriche Physik (MPE) in Garching bei Munchen. The XRT could also image onto the HRI microchannel-plate camera developed at Smithsonian Astrophysical Observatory (SAO) in Cambridge, Massachusetts, while Leicester University's EUV Wide Field Camera was a separate telescope bolted on the side. The spacecraft was controlled from GSOC (Oberpfaffenhofen/Weilheim) while US participation included the GSFC guest observer facility and the SAO science data center. Launched to a 564 x 584 km x 53.0 deg orbit on 1990 Jun 1, ROSAT was in a 244 x 250 km orbit as of 2011 Oct 10. The PSPC-C carried out the X-ray all-sky survey between launch and an accident on 1991 Jan 25, when PSPC-C was destroyed by accidentally observing the Sun during a system failure. The PSPC-B took over for the pointed-target phase of science observations, together with the HRI. PSPC-B was retired in 1994 when its gas supply was near empty and the HRI was the sole instrument between 1994 and 1998. It had higher spatial resolution than PSPC, but didn't have the energy resolution that enabled PSPC to distinguish different X-ray spectra. ROSAT was damaged after an attitude control problem on 1998 Sep 20. When performing a slew (change of pointing direction), the reaction wheels that manage the satellite's angular momentum were unable to keep up and the satellite's aperture followed the wrong track across the sky, crossing the Sun and resulting in destruction of the ultraviolet filter on the HRI. This makes it the only astronomy satellite I know of to have attempted suicide-by-solar-observing on two separate occasions. The science program was declared abandoned on 1998 Oct 28; however, the last dribble of PSPC-B detector gas was used for test observations between 1998 Dec 6 and 18. The spacecraft was abandoned on 1999 Feb 12. Debunking a tall tale --------------------- The Wikipedia page for ROSAT includes a story which says that a 1999 NASA internal report raised the possibility that ROSAT's demise was instead due to some kind of hacker attack. In 1998 there was an intrusion of some kind into the NASA-Goddard network which contained the source code for the flight software of several NASA satellites. According to the author of the report, `exploitation of the comm link could not be ruled out' - presumably the fear was that someone could use knowledge of the code to use their own ground station to command a satellite, or separately hack in to the NASA ground station. But despite the report, this just can't have happened with ROSAT. As I've confirmed with Rob Petre who ran the Goddard part of ROSAT, all we had were copies of the downlinked science data. All commanding, scheduling and operations of ROSAT were done from Germany at GSOC - NASA had no role in the spacecraft commanding. ROSAT was an elderly satellite in 1999, its main mission long completed. Its failure is not surprising and is fairly well understood. I've talked with several scientists involved in senior roles with the ROSAT mission and the unanimous opinion is that the story is ludicrous. To summarize: Someone did gain inappropriate access to an internal NASA network in 1998. As far as I know there's no evidence that restricted satellite flight software was actually downloaded. But whatever happened, it was definitely nothing to do with the malfunction of ROSAT that damaged the HRI. PSLV launch ----------- India launched PSLV-C18, a PSLV-CA core-alone variant, from Sriharikota on Oct 12. The main payload of PSLV-C18 is the Megha-Tropiques satellite, a joint Indian-French remote sensing satellite with a mass of around 1000 kg and based on the IRS bus. It carries the MADRAS microwave imager, the Saphir water vapor profile instrument, and the ScaRaB radiation budget sanner. Also carried were three small satellites: SRMSAT, from SRM University in Chennai, is a 10 kg satellite for greenhouse gas monitoring. Jugnu, from the Indian Inst. of Technology in Kanpur is a 3U cubesat-class technology satellite. VesselSat is a 29 kg small satellite built by OHB LuxSpace of Luxembourg to provide AIS (ship tracking) services for Orbcomm. The five objects are in orbits with an apogee of 867 km and perigees ranging from 780 to 850 km; the low perigee object is probably the rocket stage. GALILEO ------- Europe's first two Galileo navigation satellites were launched on Oct 21. This was also the first Soyuz launch from the Centre Spatial Guyanais. The new Ensemble de Lancement Soyuz pad is a copy of the pads at Baykonur. The Soyuz ST-B launch vehicle is the Soyuz-2-1B variant; an uprated Fregat-MT upper stage was used for the first time. The two satellites have been given the nicknames Thijs and Natalia after competition winners Thijs Paerlman (b. 2000) and Natalia Nikolaeva (b. 2002). Two earlier test satellites, GIOVE A and GIOVE B, were launched in 2005 and 2008. ViaSat-1 -------- ViaSat-1 is a Ka-band broadband data satellite launched by a Proton from Baykonur. It will provide capacity over North America. The heavy (6740 kg launch) Loral-1300 satellite is owned by ViaSat, a California-based company; the payload includes 9 Canadian spot beams owned by Telesat in addition to the 63 US beams owned by ViaSat. As of Oct 25, ViaSat-1 was in a 12291 x 35781 km x 9.5 deg orbit on its way to a geostationary location at 115W. Suborbital flights ------------------- The PICTURE payload, NASA 36.225UG, was launched from White Sands in an attempt to image an exoplanet. The CHAMPS flights, one nighttime and one daytime, were launched from Andoya to study meteoritic dust in the upper atmosphere. Table of Recent (orbital) Launches ---------------------------------- Date UT Name Launch Vehicle Site Mission INTL. DES. Sep 10 1308 GRAIL-A ) Delta 7920H Canaveral SLC17B Lunar 46A GRAIL-B ) Lunar 46B Sep 18 1633 Zhongxing 1A Chang Zheng 3B(E?) Xichang Comms 47A Sep 20 2247 Kosmos-2473 Proton-M/Briz-M Baykonur Comms 48A Sep 21 2138 Arabsat 5C ) Ariane 5ECA Kourou ELA3 Comms 49A SES 2 ) Comms 49B Sep 23 0436 IGS O-4 H-2A 202 Tanegashima Imaging 50A Sep 24 2018 Atlantic Bird 7 Zenit-3SL SL Odyssey, Pacific Comms 51A? Sep 27 1549 Tacsat-4 Minotaur 4+ Kodiak Comms 52A Sep 29 1316 Tiangong-1 Chang Zheng 2FT1 Jiuquan Module 53A Sep 29 1832 Quetzsat-1 Proton-M/Briz-M Baykonur LC200/39 Comms 54A Oct 2 2015 Glonass-M No. 42 Soyuz-2-1B Plesetsk Navsat 55A Oct 5 2100 Intelsat IS-18 Zenit-3SLB Baykonur LC45 Comms 56A Oct 7 0821 Eutelsat W3C Chang Zheng 3B(E) Xichang Comms 57A Oct 12 0531 Megha-Tropiques ) PSLV-CA Sriharikota EarthObs 58A SRMSat ) Tech 58 VesselSat-1 ) Comms/AIS 58 Jugnu ) Tech 58 Oct 19 1848 ViaSat-1 Proton-M/Briz-M Baykonur Comms 59C Oct 21 1030 Galileo IOV PFM ) Soyuz-2-1B Kourou ELS Navsat 60A Galileo IOV FM2 ) Navsat 60B Table of Recent (suborbital) Launches ---------------------------------- Date UT Payload/Flt Name Launch Vehicle Site Mission Apogee/km Sep 1 1353 ARAV? Terrier Oriole? Kauai Target 150? Sep 1 1354 Aegis KV SM-3 Block 1B CG-70, Kauai Interceptor 150? Sep 3 0946 RV Topol' Plesetsk Test 1000? Sep 26 0320 Prithvi RV Prithvi-2 Chandipur IC3 Test 100? Sep 29 10 RVs? Layner K-114, Barents Sea R&D 1000? Sep 30 0400? Agni RV Agni 2 Chandipur IC4 Test 220 Oct 5 0556? FTT-12 Target SRALT? C-17, Kauai Target 100? Oct 5 0556? FTT-12 Target ? Target SRBM MLP, Kauai Target 100? Oct 5 0600? THAAD KV THAAD Kauai Intercept 100? Oct 5 0600? THAAD KV THAAD Kauai Intercept 100? Oct 8 NASA 36.225UG Black Brant 9 White Sands Astronomy 200? Oct 11 NASA 41.094UE Terrier Orion Andoya Atm. Sci 130? Oct 13 NASA 41.093UE Terrier Orion Andoya Atm. Sci 130? .-------------------------------------------------------------------------. | Jonathan McDowell | phone : (617) 495-7176 | | Somerville MA 02143 | inter : planet4589 at gmail | | USA | jcm@cfa.harvard.edu | | | | JSR: http://www.planet4589.org/jsr.html | | Back issues: http://www.planet4589.org/space/jsr/back | | Subscribe/unsub: http://www.planet4589.org/mailman/listinfo/jsr | '-------------------------------------------------------------------------'