Large sats for solar transi

Rob Matson (Rob_Matson@cpqm.mail.saic.com)
30 Jul 1996 13:17:10 -0800

------------------------------
Date: 96/07/30 04:39 
To: Matson, Rob
From: Willie Koorts


Willie Koorts wrote:

> I ran Skymap in its transit mode and tried looking for the sats
> passing across the disk of the sun.  I had no luck yet.  I realised
> that I needed very accurate elements and should rather target
> only a few selected sats, perhaps ones with stable orbits and of
> fair size.  I have a video camera at home or if I am quick enough,
> might be able to take a photo with a camera on a tripod.
>
> Have you got a list of such suitable sats?

I started with Ted Molczan's latest element set and took a look at the
physical dimensions of the satellites.  There are around 600 in the list that
have a length of 6 meters or more.  Around 460 have a length of
7 meters or more, and only 68 have a length of at least 8 meters.

Of these 68, 55 have maximum projected areas of 20 sq-m or more,
51 have max proj areas of 25 sq-m or more, and 30 have a max projected area of
at least 30 square-meters.  I'd stick to those 30.
They are:

06212 Radcat          12.2  3.0  0.0  4.8
08074 Pageos (H)       8.6  0.0  0.0  3.7
10967 Seasat          21.0  1.5  0.0  5.1
16182 Cosmos 1697 r   10.4  3.9  0.0  4.6
16609 Mir Complex     32.7  4.2  0.0  3.4
16910 EGP r           13.5  2.5  0.0  4.9
17590 Cosmos 1833 r   10.4  3.9  0.0  4.6
17974 Cosmos 1844 r   10.4  3.9  0.0  4.6
19120 Cosmos 1943 r   10.4  3.9  0.0  4.6
19650 Cosmos 1980 r   10.4  3.9  0.0  4.6
19671 Lacrosse 1      18.0  4.5  0.0  3.9
20322 COBE             4.9  8.5  0.0  3.9
20580 HST             13.3  4.3  0.0  4.3
20625 Cosmos 2082 r   10.4  3.9  0.0  4.6
21147 Lacrosse 2      18.0  4.5  0.0  3.9
21701 UARS             9.8  4.6  0.0  4.4
22220 Cosmos 2219 r   10.4  3.9  0.0  4.6
22251 USA 86          15.0  3.0  0.0  4.6
22285 Cosmos 2227 r   10.4  3.9  0.0  4.6
22566 Cosmos 2237 r   10.4  3.9  0.0  4.6
22803 Cosmos 2263 r   10.4  3.9  0.0  4.6
23088 Cosmos 2278 r   10.4  3.9  0.0  4.6
23343 Resurs 1-3 r    10.4  3.9  0.0  4.6
23405 Cosmos 2297 r   10.4  3.9  0.0  4.6
23605 Helios 1A       10.0  3.0  0.0  5.0
23705 Cosmos 2322 r   10.4  3.9  0.0  4.6
23710 Radarsat         8.0  0.0  0.0  3.9
23712 Milstar DFS 2   50.0  0.0  0.0 -0.0
23728 USA 116         15.0  3.0  0.0  4.6
23862 NOSS 2-3 (A)    15.0  4.0  0.0  4.2

A few of these (e.g. Lacrosse 1 and 2) will not generally have "fresh" orbital
elements, so they are probably unsuitable for transit predictions.  --Rob