Ang: annular eclipse october 3rd madrid/ attention: javi el zaragozano

From: b_gimle@algonet.se
Date: Sun Sep 25 2005 - 05:03:41 EDT

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    I wrote the attached message to Dan, Russell, Gerhard (and Rob)
    Using Rob's SkyMap you can get predictions for daytime (but you
    might want to AVOID those where SP5;PA occur)
    
    Anyway, Sun and Moon are only at 28 deg elevation, so a satellite
    at 800 km crosses the shadow some 1500 km SE of Madrid,
    and in other directions it is more or less free from the dense part.
    Some satellites passing 8:58?- 1 min.:
     24966 IRIDIUM 35
     15032 SL-8 R/B
     25261 ARIANE 40 R/B
     23323 IRS P2
     11416 NOAA 6
     28680 SL-12 DEB
     13923 NOAA 8
     11672 SL-14 R/B
     13128 SL-8 R/B
     13552 COSMOS 1408
     14680 SL-8 R/B
     25695 SS-18 R/B
     26083 GLOBALSTAR M060
     10544 NOSS 2 (E)
     26222 CZ-4 DEB
    
    But I find Iridium 7 passing 09:36 (and no flare at all during eclipse)!
    
    /Björn
    
    ----- Original Message ----- 
    ...
    > how can I get predictions for if and when such objects might be visible? 
    > using starry night pro (which doesn't list too many LEO objects) for 
    > example, I notice iridium 7 is in the area at the time of the peak.  
    will 
    > it be obscured by the umbra for the entire time it's in line-of-sight 
    with 
    > madrid?
    
    ------------------------------------------------------
    
    Since SkyMap 6.1:
    
         When F8 (Check for satellites in lunar umbra) is "On", program
         determines if moon occults any portion of the sun as seen from
         the satellite.  If so, the satellite visual magnitude is adjusted
         to account for the fraction of the sun occulted.
    
         If the sun is more than 50% occulted, the satellite track color
         is set to dark blue.  (This is a slightly darker blue than the
         blue used for tracks when the earth limb is blocking part of the
         sun.)  If the sun is more than 90% occulted, the satellite track
         color is set to dark purple (a darker purple than that used for
         tracks dimmer than the satellite magnitude limit).
    
    Apart from the fact that my ability to associate the colour of a line
    with the proper description, plotting "all" satellites makes the
    graph unreadable. See Eclipse2.gif!
    
    NB - I omitted this because it is 635 kB (~800 in transmission)
    Let me know if you still want to see it!
    
    But turning on option F6 (HPGL output) creates a text file where the
    colour codes can be easily located with a good text editor (I use
    UltraEdit, which also can record macros to process the complete file)
    
    With this method I located "all" objects that showed a 'SP5;PA' from
    06:00 to 10:19 UTC above horizon from Dan Deak's location.
    I used a mag limit of 13, and range 55555 km (!) to get the list,
    but of course you can set lower limits though using the same set.
    I also set 'Horizon' mode (F7/F7) to get alt/az correct (not the star
    track) regardless of time.
    
    You can use the attached file eclipsed.sel to extract elsets for
    relevant objects from a large tle file.
    Use my program   'applysel.exe  large.tle eclipsed.sel   eclipsed.tle'
    or Mike's        'xf6.exe       eclipsed.sel   large.tle eclipsed.tle'
    but in the latter case my comments (HP plot coordinates for start
    of SP5 color code) will appear as TLE lines 0.
    
    Of Russell's suggestions, my list contains only 23561, 22566, 22220, 15944,
    13367, but #15644 is a beauty!
    
    Cosm1674c.gif shows that #15644 is predicted to dip to mag +13.5
    right after culmination, despite a favourable phase angle.
    
    Cosm1674c.bmp is an enlargement (before conversion to .gif) where the colour
    changes from SP6 to SP5, 1 second before 8:37 UTC.
    
    DanmDea6_E is a prediction for objects that could reach mag +6, but I used
    PaintShopPro to change yellow, blue, red to black in the Edit Color Palette
    menu, enhancing the SP5 sections.
    
    /Björn
    
    
    
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