Watch UARS - it's dropping!

Several news outlets are abuzz (e.g. here and here) about UARS, the defunct Upper Atmosphere Research Satellite, which is in the last days of its life.

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Launched on Space Shuttle STS-48 in 1991, it was shut down in 2005 and it's orbit lowered to speed up decay.

That moment of decay is now near, with the 6 tonnes satellite expected to re-enter into our atmosphere in the last days of September or first days of October. At this moment , it is not possible to predict the moment of decay more exactly than this, and hence it is impossible to say where (over which part of the world) the re-entry will take place. At the moment of writing, the satellite already has come down to a 244 x 275 km orbit. The nominal decay date is currently projected to be around September 28-29 but has an uncertainty of several days.

UARS is that big, that parts of it might actually survive re-entry and impact on land or sea. Modelling by NASA suggests up to 532 kg of material, broken up into tens of pieces, might survive re-entry, with the biggest piece being perhaps in the order of just over 150 kg. The odds of this debris hitting someone are small however.

UARS is a large satellite that can be quite bright and easily seen by the naked eye: in the past, I have seen it attain brightnesses up to  mag. +0.5, as bright as the brightest stars in the sky.

The image above shows UARS photographed by me on 16 June 2010 from Leiden, the Netherlands, when it showed a small flare.

Progress-M 04M, MSX, and Mentor 2

A long spell of very warm, sunny weather is resulting in several clear nights. Since my last observations reported here (those of June 2nd), I have been able to observe on June 3, 13, 14, 16, 17, 22, 24, 26 and 29. Objects include Progress-M 04M, Mentor 2, Mentor 4 (USA 202), USA 161, USA 32, USA 184, MSX, Milstar 5, the NOSS 3-1 duo, and the STSS Demo-1. This does not include a number of non-classified strays also captured.

USA 161 (01-044A) slowly flared to -1 at 23:58:59 UTC (24 Jun).

Below are a few pictures. First: UARS captured as a stray, flaring, on June 16th:

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Progress-M 04M on 26 and 29 June:

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Geostationary USA 202 (Mentor 4), in the trees low in the sky (altitude about 17.5 degrees):

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Mentor 2 (geostationary), MSX and a stray (HJ-1A, a Chinese Earth Observation Satellite)

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Lacrosse 5 "disappearance trick" over the Pleiades, UARS and ISS again

The sky keeps being clear, so last evening I had another observing session.

In twilight I observed ISS again, and filmed it again as it passed Mars and descended to the eastern horizon. Below short movie (shot with my Ixus camera in "movie"-mode) shows it (Mars can occasionally be seen in the upper right corner):



I observed UARS in twilight too, on the request of John Locker. It was about mag. +2 in the brightest part of the pass.

Lacrosse 5 (05-016A) made an initially nice & bright pass that brought it very close to the Pleiades. As I was photographing it, it did it's infamous "disappearance trick" right above the star cluster:

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Other objects observed (telescopically) this evening were USA 129 and the NOSS 3-2 duo.

Last but not least, I imaged the moon again through my Meade ETX-70:

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