SatTrackCam Leiden (b)log: Komsos 2251

Wednesday, 11 March 2009

Iridium 33 and Kosmos 2251 wreckages observed

I visually observed the main wrecks of both Iridium 33 and Kosmos 2251 with the Meade ETX-70 (7 cm F5 refractor) this evening.

The Iridium 33 wreckage (24946, 97-051C) was easy to see and notably irregular in brightness, with many short flashes (several per second, with a brighter one approximately each second. This is an estimate: I did not time them). I observed it as it passed close to Pollux near 19:55:10 UTC (11 March). At its brightest it might have been +6 or +6.5. I did not observe the kind of bright flares as reported by Simone from Italy yesterday.

The Kosmos 2251 wreckage (22675, 93-036A) was much fainter, about +8 at its brightest as it passed close to alpha Uma at 20:11:30 UTC. It too was irregular, but its brightness variation seemed slightly slower than that of the Iridium 33 wreckage.

I also observed Lacrosse 3 in twilight and got 6 positions on it.

Excerpt from United Nations resolution 2222 (XXI)

Treaty on Principles Governing the Activities of States in the Exploration and Use of Outer Space, including the Moon and Other Celestial Bodies

In order to promote international co-operation in the peaceful exploration and use of outer space, States Parties to the Treaty conducting activities in outer space, including the moon and other celestial bodies, agree to inform the Secretary-General of the United Nations as well as the public and the international scientific community, to the greatest extent feasible and practicable, of the nature, conduct, locations and results of such activities. On receiving the said information, the Secretary-General of the United Nations should be prepared to disseminate it immediately and effectively.