Phobos-Grunt
To:
"dome-l@googlegroups.com" <dome-l@googlegroups.com>
Phobos-Grunt is making a series of passes (currently in the morning pre-dawn skies over the Gulf Coast of the United States). This morning, over Houston, the spacecraft made a pass some ~34 deg above the northern-northeastern horizon. The next day’s pass will cut right through the zenith.
Originally, was ~3rd magnitude and then brightened to roughly 1st [possibly a bit brighter] magnitude for about 10 seconds. Did not see any debris or secondary fragments this morning. Steady brightness so ... probably not tumbling or turning.
The ‘easy way’ to get visibility predictions is to go to Heavens Above at:
http://www.heavens-above.com/
However, if you’re hardcore you can also do it the old-fashioned way with NORAD’s Keplerian two-line elements (TLEs) - latest is:
PHOBOS-GRUNT
1 37872U 11065A 11315.20886687 -.00002358 11386-4 12469-5 0 132
2 37872 51.4279 348.6620 0099321 34.6157 326.1098 16.00626105 383
Once did this the old-fashioned way at Strasenburgh and Abrams.
There is some concern over the hydrazine on board (~11 tons of it; it’s a 13-ton spacecraft but, most of the mass is propellant). Unlike USA-193, the hydrazine on board Phobos-Grunt is contained within aluminum tanks and upon re-entry, will likely burn up. (USA-193, aka NROL-21, was a different story — don’t recall all the details but, its hydrazine prop was frozen and would have survived re-entry and was destroyed from a RIM-161/SM-3 missile launched from the USS Lake Erie out of the Pacific.)
Emily Lakdawalla has maintained a very good running blog at:
http://planetary.org/blog/article/00003257/
For those with Russian language background, Novosti Kosmonavtiki have posted schematics of the spacecraft (from Lavochkin) on their site at:
http://www.novosti-kosmonavtiki.ru/phpBB2/viewtopic.php?t=12378
Chances of recovering Phobos-Grunt are grim, at best. Other nations and entities have offered help, including USSTRATCOM (Strategic Command was created in 1992 from SAC; in 2002, U.S. Space Command was merged into STRATCOM), but Russia has declined that assistance.
Rob Landis
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