Re: clouds

From: Greg Roberts (grr@telkomsa.net)
Date: Tue Feb 24 2009 - 21:18:46 UTC

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    Evening Gerhard
    
    I can also add to Bjoern's comments. If you look at the various satellites in 
    CLASSFD.TLE- especially the 90*** objects that have an inclination around 25-30 
    degrees or so - ideal for your latitude :-)) - you will see quite a few 
    satellites that have not been observed for a long time. These are basically 
    lost. These objects are typically large spent rocket casings in geostationary 
    transfer orbits which means they have a low perigee and a high apogee. When near 
    perigee they are naked eye objects. A typical case was 90070 which was lost for 
    a LONG time until I accidentally observed it on three occassions over a space of 
    several weeks and Ted was able to tie it all together and 90070 recovered. The 
    magnitude was typically around 2-3 magnitude so easy. If this, and similar 
    objects in CLASSIFIED.TLE are not observed more frequently they will again 
    become lost and even a report like " I saw 90070 at 19h35m UT at about 20 
    degrees elevation in the east" is good enough to give a pointer when to look. 
    Finding the ones currently lost will take a fair amount of time and the more 
    prolific observers prefer to observe 10 satellites rather than try and recover 
    one lost satellite.
    
    The KH satellites are a bit difficult for you - you are not far enough south of 
    the equator at 26 deg S so you will have limited access to some for a relatively 
    short period in the summer months.
    
    Another area where you could be very useful are the Molniya type satellites in 
    CLASSIFIED.TLE. You and I see these satellites heading towards perigee and they 
    can get quite bright - 3rd mag and some of them produce bright flashes. 
    Sometimes these satellites have long periods when they are not visible at a 
    civilised time so could become lost. Several of them carry out frequent orbit 
    changes which makes things a bit more exciting/difficult.
    
    So yes, there is plenty a casual observer equipped with binoculars and stop 
    watch can do with rough observations. Its the same sort of situation we have in 
    professional astronomy - amateurs spot things like novae,comets, variable stars 
    brightening etc which the professional would otherwise miss and the amateurs 
    give the warnings that enable the professionals to observe these objects - the 
    sky is pretty big and the more people looking, the more will be seen.
    
    Cheers
    Greg
    
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