Jonathan’s Space Report No. 508 2003 Sep 2,
Shuttle and Station
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The Expedition 7 crew, Yuriy Malenchenko and Edward Lu, remain on board
the Space Station. The Progress 247 cargo ship undocked from Zvezda on
Aug 27 and deorbited later the same day. Progress 248 (M-48) was
launched on Aug 28 and docked with Zvezda on Aug 31. The Progress
ferries are automated versions of the Soyuz spaceship and are used to
bring supplies to the Station.
The Columbia Accident Investigation Board has released its report. It’s
going to take a long time to get the Shuttle ready for flight again,
particularly since the CAIB requires NASA to develop an on-orbit method
to repair RCC leading edge panels. It will take even longer for NASA to
develop a healthy human spaceflight program management structure. There
are of course a lot of dedicated and talented people in the Shuttle and
Station programs, but I’m afraid there is rampant bureaucracy, a large
number of people who do not impress, and as an outsider I see only mild
overall improvement since the loss of Challenger. In contrast, my
impression is that NASA’s space science program is in incomparably
better health compared to its sorry state in the 1980s, with a diverse
mix of small and large missions and, despite some funding problems and
occasional failures, a remarkable rate of spectacular discoveries. That
gives me hope that similar change is possible on the human spaceflight
side of the house.
Recent Launches
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Boeing launched another Delta IVM from Cape Canaveral on Aug 29,
carrying the final DSCS III military communications satellite to
geostationary transfer orbit. The Delta 4 second stage entered a 186 x
401 km x 29.2 deg parking orbit and then a 235 x 35551 km x 25.5 deg
transfer orbit. The DSCS III, built by Lockheed Martin, is attached to
the IABS-7 upper stage with two R-4D bipropellant engines, which was
expected to be fired around Sep 1 to put the satellite in geostationary
orbit. DSCS III B-6 was originally built by GE/Valley Forge for launch
by Shuttle, and was extensively modified after the Challenger accident
and the acquisition of GE’s space division by Lockheed Martin. The
satellite has been assigned the cover designator USA-170. This was the
third launch of a Delta IV rocket; all have been successful.
According to data received from Boeing and other sources, the Delta 300
final stage used to launch SIRTF entered heliocentric orbit. When a
vehicle reaches escape velocity, its path around the Earth is a
hyperbola, in this case with an eccentricity of e=1.104. Now e=0 is a
circle, e=0.999 is a very long ellipse, so this is just a little bit
hyperbolic, but more so than SIRTF which had only e=1.006. As the
spacecraft rises out of the Earth’s gravitational field it slows down,
and approaches a fixed speed as it gets very far away. This ‘speed at
infinity’ was 2.5 km/s for Delta 300, compared to 0.6 km/s for SIRTF.
The craft also tends towards a particular point on the sky, the
‘departure asymptote’ which in the case of Delta 300 was 19 39 34 +30
50.5 (J2000) in Cygnus. After the craft reaches a million km or so from
the Earth, it mostly feels the Sun’s gravity and we can then better
describe its orbit as an ellipse around the Sun instead of a hyperbola
around the Earth. I did an approximate calculation and derived an orbit
of 0.86 x 1.01 AU x 8.2 deg, where 1 AU is the radius of the Earth’s
orbit and the inclination is with respect to the ecliptic plane in which
the planets move. Delta 300 will reach perihelion around 2004 Mar 13
about 20 million km outside the orbit of Venus. This is believed to be
the first Delta second stage to enter orbit around the Sun – usually
Delta space probe launches use a third stage solid motor for solar orbit
injection. Delta 247, which launched ACE to L1 in 1997 and achieved
close to escape velocity, made a retrograde depletion burn and is
believed to have reentered the Earth’s atmosphere.
The SIRTF dust cover was ejected on Aug 30, probably around 0300 UTC.
The aperture door was opened about a day later. The instruments are now
seeing the sky, although the telescope is not cool enough yet to do
astronomy.
The earlier reports of injuries in addition to the fatalities from the
VLS explosion in Brazil were incorrect. 21 people were killed, but there
were no other casualties.
Note
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Apologies for the glitch which caused some subscribers to get a second
copy of JSR 507!
Table of Recent Launches
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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 Aug 19 1050 Kosmos-2400 ) Kosmos-3M Plesetsk LC132/1 Comms 37A Kosmos-2401 ) 37B Aug 25 0535 SIRTF Delta 7920H Canaveral SLC17B Astronomy 38A Aug 28 0148 Progress M-48 Soyuz-U Baykonur Cargo 39A Aug 29 2313 DSCS III B-6 Delta IVM Canaveral SLC37B Comms 40A
.-------------------------------------------------------------------------. | Jonathan McDowell | phone : (617) 495-7176 | | c/o Harvard-Smithsonian Center for| | | Astrophysics | | | 60 Garden St, MS6 | | | Cambridge MA 02138 | inter : jcm@host.planet4589.org | | USA | jmcdowell@cfa.harvard.edu | | | | JSR: http://www.planet4589.org/jsr.html
