From: LARRY KLAES (ljk4_at_msn.com)
Date: Sat Aug 02 2003 - 15:18:38 PDT
----- Original Message -----
From: owner-jsr_at_head-cfa.harvard.edu
Sent: Friday, August 01, 2003 4:34 PM
Subject: Jonathan's Space Report, No. 505
Jonathan's Space Report
No. 505 2003 Aug 1, Cambridge, MA
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Shuttle and Station
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The Expedition 7 crew, Yuriy Malenchenko and Edward Lu, remain on board
the Space Station. Novosti Kosmonavtiki magazine has published its
account of the Soyuz TMA-1 landing, including the actual landing time
of 0204:25 UTC on May 4 - I haven't seen this time published in English
sources.
The Columbia investigation board has a nice analysis of the foam impact
on http://www.caib.us/news/documents/impact_velocity.pdf. One
implication they don't draw is that, counter to the gut assumption made
in pre-accident discussions, low density foam is arguably WORSE than
high density ice. The change in velocity due to drag is proportional to
one over the density, so the kinetic energy of impact is (1/2) mass
times velocity squared, which is proportional to density times
(1/density) squared, which is (1/density): the velocity change wins out
over the mass increase, and low density material packs MORE bang
(energy) and the SAME wallop (momentum m dv) as more dense material.
However, it has been pointed out to me that the physics of the collision
is a bit more complicated, for example due to differences in elasticity
the foam collision probably deposits a smaller fraction of its energy,
so that may cancel out the effect. Clearly from the imagery there are
pieces of foam debris after the collision which still have significant
energy.
Recent Launches
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On Jul 17 Lockheed Martin launched AV-003, the first 500-series Atlas V.
It is a 521 variant with a 5-m fairing, two Aerojet strapon solid
boosters, and a single-engine Common Centaur upper stage; the previous
two Atlas V launches were 400-series missions using a smaller fairing
and no strapons. The enormous fairing made AV-003 highly reminiscent of
a Titan IV. The vehicle entered a 167 x 4166 km x 27.1 deg parking orbit
15 min after launch, according to Spaceflightnow.com (Justin, thanks
again for continuing to include these figures in your commentary, as the
ILS webcast commentators never bother to quote them). The Centaur
restarted near apogee and delivered the payload to a high-perigee
geostationary transfer orbit of 3815 x 35761 km x 17.5 deg.
This was the first flight of the Aerojet Atlas V SRM boosters, which
with a mass of 46t and a size of 19.2m long, 1.6m diameter are
comparable to the first stage of the MX/Peacekeeper ICBM (shorter and
fatter at 10.7m long 2.3m diameter) - much bigger than the Delta
GEM strapons, but much smaller than the Ariane 5 and Titan 4 SRBs.
AV-003's payload is Rainbow 1, a satellite built by Lockheed Martin in
Sunnyvale (the rocket is built by the Denver branch of LM). The A2100AX
class satellite has a launch mass of 4328 kg and will be used by
Cablevision Systems Corp of Bethpage, NY. By Jul 23 Rainbow 1 had used
its Leros engine to reach an orbit of 10529 x 35746 km x 8.8 deg,
and by Jul 29 it was on station at 62 deg W in a 35644 x 35931 km x 0.1
deg geostationary orbit.
Canada's MOST astronomy satellite is successfully undergoing on-orbit
checkout, with first light expected in the coming weeks.
Questions For Readers
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I'm trying to improve my log of objects in the geostationary corridor,
adding debris that is not in the Space Command satellite catalog. It
turns out that a number of geostationary weather satellites have ejected
lens caps into orbit: Meteosat Second Generation (MSG 1) ejected two,
although the recent GOES satellites have their cooler covers on hinges
rather than ejecting them. I would be grateful if anyone who has worked
on the earlier Meteosat, GOES/SMS, or NASDA GMS satellites can tell me
whether or not these satellites ejected cooler covers. (For extra
credit, provide ejection dates/times, dimensions and mass, and the same
info for the ejected lower despun sections containing the spent apogee
motors). Anyone else littering the geostationary band is encouraged
to own up (e.g. telescope covers like those ejected from the DSP
satellites).
One funky example I came across in this search was the Canadian CTS
(Communications Technology Satellite), launched in 1976. As with many
satellites, it was spin-stabilized during the coast to geostationary
orbit and prior to deploying its main solar array wings. Unusually, it
got power during this period from an extra set of solar arrays mounted
outside the folded-up array wings. Once CTS reached geostationary, it
ejected these extra arrays, called JBSA (Jettisonable Body Solar
Arrays), reducing its angular momentum and allowing the main wings to
unfold (Acta Astronautica 5, 343). The 1.8-meter JBSAs do not currently
appear in the satellite catalog, which is noticeably incomplete for
older objects in high equatorial orbit - until the late 1980s, the US
sensor net was still optimized for quickly distinguishing satellites
from incoming missiles, and tracking high altitude debris was not a
priority. CTS pioneered Ku-band satellite communications, and was
used for early tests of broadcasting to remote locations in both
Canada and Australia.
Fun (Educational) Toys
-------------------------------------
Dave Doody, from Cassini Flight Ops, draws my attention to
http://www.jpl.nasa.gov/scalemodels/
Other News Sources
------------------
Brian Webb asked me to draw readers' attention to his free email
newsletter concentrating on the Vandenberg area,
http://home.earthlink.net/~kd6nrp/newsletter.htm
The spaceflightnow.com site, Stefan Barensky's site, www.orbireport.com,
and Aleskandr Zheleznyakov's site (in Russian)
www.cosmoworld.ru/spaceencyclopedia/hotnews/, remain the best other
general sources of timely on-line space information which contain original
(primary source) information.
Table of Recent Launches
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Date UT Name Launch Vehicle Site Mission INTL.
DES.
Jun 2 1745 Mars Express Soyuz-FG/Fregat Baykonur LC31 Probe 22A
Jun 4 1923 Kosmos-2398 Kosmos-3M Plesetsk Navigation 23A
Jun 6 2215 AMC-9 Proton-K/Briz-M Baykonur LC200/39 Comms 24A
Jun 8 1034 Progress M1-10 Soyuz-U Baykonur LC1 Cargo 25A
Jun 10 1356 Thuraya 2 Zenit-3SL Odyssey, Pacific Phone comms 26A
Jun 10 1758 MER-A Spirit Delta 7925 Canaveral SLC17A Mars probe 27A
Jun 11 2238 BSAT-2c ) Ariane 5G Kourou ELA3 Comms 28A
Optus/D C1 ) Comms 28B
Jun 19 2000 Molniya-3 Molniya-M Plesetsk LC43/3 Comms 29A
Jun 26 1853 Orbview-3 Pegasus XL Vandenberg RW30/12 Imaging 30A
Jun 30 1415 Monitor-E mockup) Tech 31A
Mimosa ) Science 31B
MOST ) Rokot Plesetsk LC133 Astronomy 31D
CUTE-I ) Tech 31E
Quakesat ) Science 31F
Can X-1 ) Tech 31H
Cubesat XI-IV ) Tech 31J
AAU-Cubesat ) Imaging 31G
DTUSat ) Tether 31C
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
.-------------------------------------------------------------------------.
| Jonathan McDowell | phone : (617) 495-7176 |
| Harvard-Smithsonian Center for | |
| Astrophysics | |
| 60 Garden St, MS6 | |
| Cambridge MA 02138 | inter : jcm_at_cfa.harvard.edu |
| USA | jmcdowell_at_cfa.harvard.edu |
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