Brad Young had some questions to ask about the MiTEx objects as follows: >I've been dying to ask a few questions, now that it is appropriate: Will try and asnwer as best I can . If I talk rubbish Im sure someone better qualified will add their bit or pit me right. >Excuse my ignorance of determining satellite albedo, but this object seems >rather bright for a small satellite intended to be easily maneuvered and >with stealth capabilities. I assume this is because the solar panels are the >major reflective surface, and they must be of some size to support any >operations on the satellite (imaging, telemetry, etc.). Perhaps the bird has >a much fainter radar image? Im not 00% sure which object you are referring to so will deal with all three. The MiTEx launch placed three major objects in orbit - the two small MiTEx satellites and the MiTEx upper stage. For some time we have had an object in the element sets that was called MiTEx simply because we did not know which one of the three it was. We now know that this is the biggest and brightest object so we suspect its the upper stage and is now identified as such in the element sets. It is not that easy an object but it appears to be flashing at a fairly regular interval and the flashes are quite bright so if you watch the predicted position for (say) a few minutes you should see flashes which make it easy to track. If the phase angle is correct you may not need the flashing because then its fairly easy. If the elements are fairly recent then there is a good chance it will be close to where predicted as its regularly tracked. The object called 91132 is probably a MiTEx proper. Since we have been unable to find the other MiTEx object this is most likely the second largest object from the launch. I dont know which one it is. It was only found because I suspect DSP-F23 would be examined by one of them so all one had to do was monitor the vicinty of DSP-F23. It is NOT an easy object. I have had to use relatively long exposures and normally have to wait for the phase angle to improve - I found it usually got brighter around phase angle 39 degrees or so so I would think the magnitude is appropiate for its size- whatever the physical size might be. It also appears to exhibit small relatively long period variations of less than half a magnitude variation. I consider it perhaps one of the most difficult objects I have tracked and frankly expect that we will loose the satellite once it passes out of range to Peter and myself. If it does another orbit change after this then the likely hood of it being found again is remote - unless Scott (say) finds it by accident over your part of the world as he has the most sensitive amateur setup. >Or, could this be the final stage, with its own panels, as it thought to be >a next generation engine with more sophisticated controls? already dealt with - this is the object currently in the element file. >Finally, as a "concerned taxpayer" why can we see this thing? And, in the >same breath, when? I can't wait for it to maneuver back to the Western >Hemisphere. That I cant answer. Does it really matter if one can see it ? - other than perhaps knowing where it is there is not much one can glean from it or do about it. I dont know if it was equipped with stealth capability - I doubt it. Finally - "you cant wait to see it" -- in my case Ill be quite happy never to see it again - its too much like hard work. Its slowly drifting eastward- I have seen a suggestion that its may be going to check out the NROL-26 payload which I understand is MENTOR 4. If it does any orbit change then I dont think you stand much of a chance seeing it by the time it drifts over to your part of the world. As to the other MiTEx I think we can totally forget about it - its probably around magnitude +15 or fainter. Hope this answers your questions. I plan to track again tonight and try and see 91132 again. If its moved then I could be in for a long search - when I first looked for it it took several hours all told plus numerous exposures and even then I wasnt 100% confident that I was observing a satellite.This was with the 200mm focal length camera- aperture 70mm. I now use the 6 inch reflector ( aperture 150 mm) as this gives me another 2-3 magnitudes gain, but with half the size field of view and even then its difficult and impossible with a moon brighter than about 3/4 full. Cheers Greg ------------------------------------------------------------------------- Subscribe/Unsubscribe info, Frequently Asked Questions, SeeSat-L archive: http://www.satobs.org/seesat/seesatindex.html
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