Atlantis was rolled to the VAB on Apr 20 and was mated with the external tank and SRBs on Apr 21. Launch is to be no earlier than Jun 19.
Atlantis was rolled out to pad 39A on Apr 26 for mission STS-71; Discovery was rolled from the Orbiter Processing Facility to the Vehicle Assembly Building on May 3 and mated to the external tank and solid boosters for mission STS-70 the same day. It has now been decided to fly Discovery before Atlantis. Discovery will carry a TDRS communications satellite into orbit.
Discovery was rolled out to pad 39B on May 11, joining Atlantis which has been on pad 39A for two weeks. Launch of Discovery is scheduled for Jun 8. Crew are Col. Tom Henricks, USAF (Commander); Kevin Kregel (Pilot); and mission specialists Maj. Nancy Currie, US Army, Dr. Donald Thomas, and Dr. Mary Weber. Kregel and Weber are making their first flights. For those pedants who keep track: Nancy Currie, born Nancy Decker, was called Nancy Sherlock at the time of her previous mission - I think this is the first time someone has flown twice under different names.
Discovery's mission is STS-70. The only major cargo bay payload is the TDRS-G communications satellite with an IUS upper stage, mounted on an IUS tilt table in the cargo bay.
The docking time of Progress M-27 was 2100 UT on Apr 11, not 2300 UT as I reported last month. Included in Progress M-27's cargo was a small geodetic satellite built by Kayser-Threde for the Geoforschungszentrum Potsdam, Germany. GFZ-1 is a 21 cm diameter, 20 kg sphere covered with laser retroreflectors. It was ejected from Mir's science airlock at 1912 UT on Apr 19 and given the international designation 1986-17JE. GFZ-1's orbit was 92.34 min, 383 x 394 km x 51.6 deg on Apr 20.
EO-18 cosmonauts Vladimir Dezhurov and Gennadiy Strekalov carried out their first spacewalk on May 12, starting at 0420 UT. The cosmonauts used the airlock on the Kvant-2 module, and the EVA lasted 6 hr 8 min. The purpose of the spacewalk was to prepare for removal of the Kristall solar arrays and their transfer to the Kvant module.
ESA's ERS-2 Earth Resources Satellite was launched on Apr 21 by Ariane flight V72. The spacecraft, built by Dornier for the European Space Agency, will be operated in tandem with ERS-1. It is based on Matra's SPOT bus, and carries a hydrazine engine for precise orbit control. ERS-2 has a 10-m long SAR (Synthetic Aperture Radar) for C-band radar imaging of the Earth. Its primary mission is to study the sea surface and polar ice. The SAR is linked to an Active Microwave Imager instrument; also carried are a radar altimeter for wave heights, the ATSR Along Track Scanning Radiometer for sea surface temperatures, and the PRARE orbit determination experiment. These are all similar to experiments aboard ERS-1; ERS-2 also carries a new GOME global ozone monitoring experiment. ERS-2 entered a 100.56 min, 783 x 786 km x 98.6 deg orbit.
According to Michelle Lyle of Arianespace, this V72 launch and the preceding V71 launch both used the H-10+ third stage. An enhanced third stage, the H-10-3, was first used on V70 and will be phased in to eventually replace the H-10+. The Ariane is usually flown to geostationary transfer orbit; flights to sun-synchronous orbits are rarer, and usually carry secondary microsatellite payloads. No secondary payloads were carried on this latest mission.
Contact with the Clementine space probe in solar orbit has now been fully regained. Not enough fuel remains for an asteroid encounter, so a burn was due to be made last week to slow the probe's drift away from Earth to maximize communications time.
A classified US satellite was launched at 1345 UT on May 14 from pad 40 at Cape Canaveral Air Station by Titan Centaur TC-17. The Titan 401 model core stage was serial no. K-23. In the past, classified Titan 401 missions have orbited geostationary and highly elliptical orbit signals intelligence satellites. I don't have any details yet on the current mission.
Jonathan McDowell (© Jonathan McDowell 1994)