Sven Grahn
The Astra 1M satelite was launched by a Proton-M launch vehicle from Baikonur in Kazakhstan at 2044 UT on 5 November 2008. I picked up the news of the launch on www.spaceflightnow.com about an hour after launch and immediately set up the receiver on 1018.5 MHz. I checked once on 1020.5 MHz (the alternate telemetry frequency) but did not pick up any signals. This is not to say that "absence of evidence is evidence of absence"! However, I let my SDR-14 record the signal spectrum around 1018.5 during the night between 5 and 6 November. As I left home at 0700 UT there was a strong single carrier on 1018.5 MHz. The table below summarizes all receptions made.
For a more competet account of Briz-M tracking, check out an account of the first such reception here .
Reception # | Date | Time (UT) | Notes | Time from lift-off | Adjacent mission event |
1 | 6 November 2008 | 0056-0123 | Three carriers, 0, +/- 16 kHz | +4:02 to +4:39 | Briz-M shutdown at 0031 UT |
2 | 6 November 2008 | 0154-0254 | Two carriers, +/- 16 kHz | +5:10 to +6:10 | |
3 | 6 November 2008 | 0337-0353 | Two carriers, +/- 16 kHz | +6:53 to +7:09 | |
4 | 6 November 2008 | 0527-0559 | Two carriers, +/- 16 kHz | +8:43 to +9:15 | Briz-M firing 0537-0543 UT. The S/C separated at 0556 UT |
5 | 6 November 2008 | 0609-0612 | Single carrier | +9:25 to +9:28 | |
6 | 6 November 2008 | 0650-0657 | Single carrier | +10:06 to +10:13 |
It is instructive to compare these receptions with those made on 19 August 2008 during the transfer orbit of Inmarsat 4-F3. See the table here. It is possible that the Briz-M stage transmiitted on 1020.5 MHz during the first four hours of the flight.
For clarity's sake I have filled in all signal traces with yellow colour.
The strange shapes of the spectrogram traces are explained in a previous article on Briz-M tracking.