To capture the first PI9CAM observation of Curium-One: we observed simultaneously in horizontal polarization (9841326) and vertical polarization (9841327). The signal is best in vertical polarization, probably due to a difference in our local signal chains.
About TLEs: I read in the schema above that the Curium One TLE should be in (60239, 60240, 60241, 60242, 60243) - please correct me if I read this wrong. We tracked 60242 and the telescope managed to keep pointing within 0.2 degrees of that TLE. During the observation, both 60239 and 60240 were over 3.5 degrees away, I think outside of the main beam. 60241 and 60242 are almost identical, 60243 was about 1.5 degrees away from the pointing, I’d say at the edge of the beam.
Probably this one observation is not enough to identify the right TLE from Doppler. We will try to observe 60242 again tonight to get some more data points.
You are right @tammojan about the tracking, we follow the object 60242 and the other were possible ones. Running ikhnos in the above observations show what you confirm with the degrees, that curium one is either 60241 or 60242.
However I want to do some more analysis before updating the status table, maybe later today.
Another thing that also is important, is that the TLE was 1.1 day old from the start of the observation, while in that height you don’t expect to change a lot in 1.1 day, given that the TLE are still in TBA status I don’t “trust” them 100%.
That would be great and will give the opportunity to verify our findings! Maybe it will need some days to past and have better separation for more secure results.
By the way I would like in this post to thank you and all of the station owners that contribute to the SatNOGS project and make it real. It is all of you make it useful and helpful for the Space exploration!
Hello,
This is a recording of one of the passes, recorded at 1.152 MSps with a PlutoSDR (XQuad antenna, with LNA) as IShort. I recommend a scale factor of 32767 when converting to Complex. It should have around 6 or 7 beacons, from which we could only decode 2 (for now).
If you want to iterate quicker, we are available to chat offline.
I guess this was done using the latest TLE sets for these objects right?
Given that these TLE sets are already almost 2 days old, what is the timestamp for your acquired gps data?
What I’m trying to understand is how long they are away from the TLE epoch and how much accurate the obvious visible fit with 60237 object is.
Of course at the specific height the orbital parameters don’t change that often, which means that even 2 days old TLE are still pretty accurate. So, with this GPS data confirmation I think that for now is fully safe to say that 60237 is GRBBeta, and if the next version of the TLE sets is assigned and without TLE swaps then we can move to identification.
We’ve just got new TLE sets, still not assigned except the one of the upper stage.
From a quick look we have at least one swap, so with the new data and some observations this is the current assignment to follow for each satellite in DB:
60235 is upper stage
60243 Robusta
60242 Curium
60240 OOV
60239 Replicator
60236-60238 ISTSAT, GRBBeta and 3cat4
60241 Curie
I’ll try a more detailed check tomorrow and I’ll update the thread with a new post.
This is the latest status update after the recent update of TLE sets from space-track.org and the latest Network observations. Three main changes, reception of Curium One, significant change of 60241 object position, 3Cat-4 last reception at 2024-07-10 18:10. Given all the above here is the current status:
This is the latest status update after the recent update of TLE sets from space-track.org (now almost 1.5 days old) and the latest Network observations.
We have two identifications, ROBUSTA-3A and Curium One and better fits for ISTSAT-1 and GRBBeta, still no new reception for 3CAT-4:
Given its position/orbit this could be a small satellite
60242
MEDIUM
CURIUM ONE(12U)
Identified
60243
SMALL
ROBUSTA-3A(3U)
Identified
Here we see something strange, while we expect 5 SMALL objects, we have only 4. To be honest this is the first time I use this value in identification process, so I have no experience why this happens, how accurate are the values and if and how often they change.
For the people here from the missions, please let me know if the sizing described in the table above is right for your mission.
EDIT: I forgot the parameter that the satellites may expand in size during in orbit (deployable antennas/panels etc), so the RCS SIZE expected should not be based on the initial size of the satellite.
Adding this parameter in the equation, I’m not changing the status but I’m updating the table with the “RCA SIZE” values. Forgot to mention that “unlikely” inside the parenthesis is based on the RF observations and how much they fit with each object.
The new data is the expandable antenna of 3CAT-4, which gives it a final size of 10x10x60cm, which probably could be taken as a MEDIUM object, this would explain the “missing” small size object.
Again, let me note that is the first time I use RCA SIZE values and this kind of analysis may hide errors, so here is the updated table:
3Cat4 is 1U (10x10x10) in the stowed configuration, and when deployed, its antenna will make it 10x10x60 cm. As of now, it should still be stowed (as per the latest telemetry, and the loss of contact).
