From: "Ted Molczan" [molczan@home.com]
To: "'Thomson, Allen'" [thomsona@flash.net]
Sent: Wednesday, January 24, 2001 07:21 PM
Subject: A bit of funDear Allen,
I was looking at the sample de-classified Corona images on NRO's web site, and I thought it would be fun to find the elset of the satellite that took one of the images.
I chose the Severodvinsk shipyard, which appears to have been imaged at near zero off-nadir angle:
http://www.nro.gov/index10.html
Heavens Above provides the following co-ordinates for Severodvinsk: 64.567 N 39.833 E.
The image was taken on 1969 Feb 10.
As far as I known, the only U.S. imager in orbit at the time was KH 4B-20 (69010A / 3672), which had been launched on 1969 Feb 05.
The epoch of this elset is less than 4 h before a pass that culminated 86 deg above the horizon of Severodvinsk on 1969 Feb 10 at 09:52:06 UTC:
KH 4B-20 8.0 1.5 0.0 6.0 d 1 03672U 69 41.26838673 .00415800 00000-0 28427-4 0 76 2 03672 81.5661 166.5842 0103302 132.4633 228.5323 16.22581774 705I have appended the ephemeris.The image was taken at a range and altitude of 158 km, near the perigee of the 143 km by 290 km orbit.
Best wishes,
Ted
10/ 2/69 00:00 - 24:00 UTC J2000.0 EL > 15 Severodvinsk KH 4B-20 69010A 3672 Bull = 7 SGP4 Age = 0.1 d Unc = 0 s ( 50%) TIME %I Mv AZ EL R.A. DEC FE VANG RANGE ALT -------- -- ---- --- -- -------- --------- -- ---- ----- ----- 09:50:58 91 4.0 342 14 11:23:07 38:44:31 6 0.28 542 161 09:51:13 89 3.6 342 19 11:26:23 43:41:07 6 0.41 433 160 09:51:23 87 3.2 342 24 11:30:02 48:26:05 6 0.57 363 160 09:51:30 85 2.9 343 29 11:34:07 52:54:19 6 0.74 315 160 09:51:35 83 2.7 343 33 11:38:36 56:56:39 6 0.92 283 159 09:51:39 80 2.6 343 37 11:43:58 60:51:08 6 1.09 258 159 09:51:43 77 2.4 344 41 11:52:25 65:31:00 6 1.32 234 159 09:51:46 75 2.3 344 46 12:02:50 69:36:04 6 1.52 218 159 09:51:49 71 2.2 345 50 12:21:08 74:13:59 6 1.75 203 159 09:51:51 69 2.1 345 54 12:43:21 77:35:51 6 1.91 194 159 09:51:53 66 2.1 346 58 13:25:56 81:02:51 6 2.09 185 159 09:51:55 62 2.0 347 62 15:04:08 84:02:25 6 2.26 178 159 09:51:57 59 2.0 348 67 18:16:52 84:37:35 6 2.43 171 158 09:51:59 55 2.0 351 72 20:36:01 81:39:51 6 2.58 166 158 09:52:01 51 2.1 355 77 21:34:40 77:07:15 7 2.71 162 158 09:52:02 48 2.1 359 79 21:51:03 74:36:07 7 2.76 161 158 09:52:03 46 2.1 5 82 22:03:02 71:59:16 7 2.79 160 158 09:52:04 44 2.2 19 84 22:12:09 69:18:31 7 2.82 159 158 09:52:05 42 2.2 50 86 22:19:17 66:35:16 8 2.83 158 158 09:52:06 39 2.3 98 86 22:25:02 63:50:41 10 2.83 158 158 09:52:07 37 2.3 126 84 22:29:44 61:05:47 11 2.82 159 158 09:52:08 35 2.4 137 82 22:33:40 58:21:32 11 2.79 160 158 09:52:09 33 2.5 144 79 22:36:59 55:38:47 11 2.75 161 158 09:52:10 31 2.6 147 76 22:39:51 52:58:17 12 2.70 162 158 09:52:11 29 2.7 150 74 22:42:19 50:20:45 12 2.65 164 158 09:52:13 25 2.9 153 69 22:46:24 45:16:46 12 2.50 169 158 09:52:15 22 3.1 154 64 22:49:38 40:30:23 12 2.34 174 158 09:52:17 19 3.3 155 60 22:52:15 36:03:43 12 2.17 181 158 09:52:19 17 3.6 156 56 22:54:24 31:57:35 12 1.99 189 158 09:52:21 15 3.8 157 52 22:56:14 28:11:51 12 1.82 198 158 09:52:23 13 4.0 157 48 22:57:47 24:45:42 12 1.66 208 158 09:52:25 12 4.3 158 45 22:59:08 21:37:53 12 1.51 218 157 09:52:28 10 4.6 158 41 23:00:51 17:27:20 12 1.31 235 157 09:52:31 8 4.9 158 37 23:02:17 13:49:38 12 1.14 252 157 09:52:35 7 5.3 159 33 23:03:51 09:42:07 12 0.95 277 157 09:52:39 6 5.7 159 30 23:05:09 06:14:24 12 0.80 302 157 09:52:44 5 6.0 159 26 23:06:30 02:38:33 12 0.66 336 157 09:52:50 4 6.4 160 23 23:07:48 -00:51:40 12 0.53 377 157 09:52:58 4 6.9 160 19 23:09:11 -04:32:27 12 0.41 434 156 09:53:08 4 7.3 160 15 23:10:33 -08:03:22 12 0.31 506 156 09:53:21 3 7.7 160 12 23:11:55 -11:28:25 12 0.23 602 156