This repository contains data files for the TLE identification of the EASAT-2 and HADES satellites from AMSAT-EA, which were launched on 2022-01-13 in the SpaceX Transporter-3 launch.
The files are intended to be used with the strf software.
EASAT-2 was not detected. The HADES signal strength and stability appears as usual. TLE 51074 from Celestrak is a very good fit for DELFI-PQ. It is not a such a good fit for HADES, but perhaps that's just because of the frequency instability. Fitting in mean anomaly to HADES we get a 5 second change in TCA. This is the only TLE from Celestrak that matches either DELFI-PQ or HADES, so there are still missing TLEs.
Another observation with Allen Telescope Array. At first look, the signal
strengths are the same as in the previous observation. The frequency reference
of EASAT-2 drifts much more than in the previous observation, making it difficult
to get good Doppler data. The satnogs-2022-01-16-DELFI-PQ.tle was used for tracking.
This TLE was taken from here.
This TLE has been fitted to the Doppler data of the three satellites, allowing changes in mean anomaly. The original TCA of 17:58:56 has changed as 17:58:58, 17:58:49, and 17:58:55 for DELFI-PQ, EASAT-2 and HADES respectively. The result for EASAT-2 is doubtful, gien the low quality of the Doppler data and the fact that DELFI-PQ and HADES still seem to be only 3 seconds apart.
An observation with Allen Telescope Array has been done, detecting good signals
from EASAT-2 and a very weak signal that could be HADES. The satnogs-2022-01-15-DELFI-PQ.tle was used for tracking. This TLE was taken from
a thread in the Librespace forums.
The Doppler data files corresponding to this observation are 2022-01-15_ATA_DELFI-PQ.dat,
2022-01-15_ATA_EASAT-2.dat and 2022-01-15_ATA_HADES.dat.
The satnogs-2022-01-15-DELFI-PQ.tle is a good match for all the three Doppler
data files. A fit in mean anomaly was done to try to judge the separation of the
three satellites in the along-track dimension. With
satnogs-2022-01-15-DELFI-PQ.tle, the predicted TCA for ATA of DELFI-PQ was
18:11:26. By doing a fit in mean anomaly we obtain TCA's of 18:11:35, 18:11:37
and 18:11:34 for DELFI-PQ, EASAT-2 and HADES.
The resulting TLEs obtained with this fit are
AMSAT-EA-2022-01-15-DELFI-PQ.tle, AMSAT-EA-2022-01-15-EASAT-2.tle and
AMSAT-EA-2022-01-15-HADES.tle. Observers are advised to use the
satnogs-2022-01-15-DELFI-PQ.tle instead of these, since it is based on data
from several passes.
The conclusion is that the three satellites are still close, and perhaps only 3-4 seconds apart at most. This data is relevant for the radiometric study of the ATA data, since it suggest that all the satellites were present in the primary beam of the antennas. A separation of 1 second is on the order of 0.8 deg separation on the sky at TCA on an overhead pass. The ATA FWHM at 436 MHz is around 3.8 deg.