Letter from LtCol Freer of USAF Space Ops, acknowledging that the signal problem with GPS bird PRN 19 went unnoticed by the GPS monitoring system, and was found and isolated in cooperation with Trimble and U of Leeds. It was corrected 4 Jan; the exact cause of the problem is not yet understood.
NASA budget gives Magellan a six-month reprieve, allowing completion of the low-orbit gravity-mapping effort and possibly some other experiments (notably bistatic radar tests, but no more "normal" radar work).
MSTI-2, second BMDO LEO sensor-test bird, being prepared for late-March launch (by Scout from Vandenberg).
Columbia launch set for 3 March, carrying USMP-2 (microgravity materials) and OSTA-2 (space-environment tests).
McDonnell-Douglas reschedules Cape Delta launch of Galaxy 1R to 18 Feb, after pinning the 9 Feb pad abort on a failed pressure switch in a vernier engine.
Norman Thagard and Bonnie Dunbar leave for Russia to start training for a Mir mission. [Reportedly, Thagard was chosen because he's the only active astronaut who speaks Russian at all well.]
FAA declares GPS operational for US civil aviation 17 Feb.
Mission To Planet Earth is having money woes. EOS-AM1, the first EOS bird, is on track for 1998 launch... but FY95 funding for EOS is not adequate to keep EOS-PM1, the next, on schedule for 2000. NASA is looking at the possibility of shrinking PM1 to fit on a Delta instead of an Atlas 2AS to save money; the same idea is being discussed for AM2. The first Earth Probe smallsat, this one carrying a TOMS ozone mapper, is set for May launch on Pegasus... but program funding is not adequate to start work on the second. There has been extensive bickering over who was going to pay for Landsat 7, resolved this week by the White House assigning it to NASA (which is not entirely happy about this development, despite some transfer of DoD money accompanying the transfer of responsibility).
NRC panel criticizes the design of EOSDIS, the ground end of EOS, for being too centralized and not coherent enough. NASA says changes are being made.
JPL RFP for first Mars Observer replacement imminent. It will call for an all-new design, substantially smaller (1t vs. 2.6t) to make it fit on a Delta, for launch in 1996. It will carry copies of five (out of seven) of the MO instruments. (The last two -- the gamma-ray spectrometer and the pressure-modulated infrared radiometer -- plus a lander data-relay package will be aboard a second, even smaller, orbiter that will go up in 1998.) The five instruments were chosen with an eye on early data return for selection of lander sites, plus mass and cost. The orbiter will be rocket-braked into an elliptical capture orbit, after which it will aerobrake over a four-month period to reach a 2hr circular mapping orbit. The nominal mapping mission will start in Jan 1998 and run for two years, with a possible extended mission as a data relay for landers lasting another three.
The one MO instrument that looks like a problem is the magnetometer. The instrument itself is fine, but the designers would like to eliminate the boom that held it away from MO's body. This would simplify the spacecraft, and might be necessary for the aerobraking operation.
Clementine approaches the Moon. The spacecraft is working well. Its nickel-hydrogen battery passed an inadvertently-severe test when a communications foulup on the ground discharged it rather more deeply than intended. Image of Earth from 300,000km, taken by Clementine's 500g UV/vis camera. [Not much showing, mostly the night side.] Another image, taken from 200,000km by one of Clementine's star trackers [!], showing lights of Denver, Colorado Springs, Pueblo, and Albuquerque.
Discovery lands at KSC 11 Feb.
Article talking about micro-sensor technology for small spacecraft. JPL has developed an electron-tunneling transducer [sounds like the same technology as the scanning tunnelling microscope] that can measure very small mechanical displacements. This has been used to build several sensors. A thermal-IR detector about 1mm on a side measures the thermal expansion of a trapped gas; it's not yet as good as more orthodox IR detectors, but it's within a factor of five... and it does not require a heavy, vibrating, power-hungry cooling system. Microphones and accelerometers are trivial. A magnetometer -- with rights for commercial applications already licensed by Eaton Corp. -- measures motion of a magnetic coil. Others are possible. Also of note is the Mesur Pathfinder seismometer, not using this technology but impressive in its own right: it will fit on your palm, but at JPL it can detect ocean waves on the beach 50km away. Drawing of Cassini, Pluto Fast Flyby [looking like a part fallen off Cassini], and a hypothetical "second generation microspacecraft" weighing 5kg. For PFF, JPL wants an instrument set weighing at most 7kg -- vastly smaller than the MO instruments, although broadly comparable to Clementine's.
Article on "hyperspectrometry", which seems to be the new buzzword for imaging spectrometers (which return a detailed spectrum, not just total intensities over a few broad bands, for each pixel in an image). Multispectral image, combining Landsat images from 1975, 1986, and 1992, showing massive deforestation in the Chiapas region of Mexico.
"...the Russians are coming, and the | Henry Spencer @ U of Toronto Zoology launch cartel is worried." - P.Fuhrman | henry@zoo.toronto.edu utzoo!henry