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“Kavoshgar” Launch Site shown in yellow; Satellite and rocket body shown in white

There will be plenty of time to discuss the security implications of Iran’s Omid satellite but for right now, let’s take a minute to appreciate the technological feat it represents! In the face of world opposition and sanctions, Iran has joined a very exclusive club: those countries that have managed to orbit a satellite. NASA has posted the first orbital elements of the satellite and its third stage rocket body and, running the orbits backwards, they are totally consistent with a launch from the “Kavoshgar” launch site at 18:38 on 2 February 2009 (GMT). Both the satellite and the rocket body come together and pass over the launch site at that time. The objects both have inclinations of about 55 degrees which is consistent with a launch toward the South East, which does not fully take advantage of the rotation of the Earth and was presumably chosen for range safety issues. (Sorry, a previous version of this post was somewhat confused on this point due to my wanting to get it posted as soon as possible!) The objects ended up in orbits with apogees of 322 km and perigees of 242 km. The orbital period of 90 minutes implies an orbit that is slightly lower than the Iranian statement of 14 orbits per day but not troublingly so. (My guess is that Iran must have had sufficient telemetry to do a preliminary orbital analysis at the time of the satellite separation though the satellite would certainly have been visible from Iran after its first orbit.)

The two stages to the Safir launcher that are visible in the pre-launch photos would not, I believe, get a satellite into orbit. The most likely explanation is a solid-propellant third stage inside the clam shell nose faring. What would be helpful is if somebody (amateurs?) watched the brightness of the rocket body (once that is definitively identified) to see if we can get some indication of its size from that. There should definitely be a considerable size difference between Safir second stage (which is about 5 m long and 1.25 meters in diameter) and a hypothesized third stage inside the clamshell.

Update: Amateur satellite observers in the UK have have used the radio signals from 2009-004A to determine it is the satellite. Optical observations seem to indicate that the rocket body is considerably brighter (mag. 4.5) than the satellite (which varies between 5 and 7). This would seem to favor the two stage hypothesis: Iran has probably developed a more powerful fuel/engine combination for the second stage! Now we can start being concerned about the security implications.