Transporter-13 Rideshare : VSFB SLC-4E : 15 March 2025 (06:39 UTC)

[rcampana]

We have confirmation of the deployment of HERMES H1 from ION.
Updated TLEs:

1 10224U 25999XX  25083.53441267  .00004178  00000-0  25708-3 0  9998
2 10224  97.4435 338.6973 0003998 289.0728 299.1526 15.16619594 59103

[PE0SAT]

@fredy

98615

Converted to temporary SatNOGS Norad ID

HERMES H1
1 98615U          25083.53441267  .00004178  00000-0  25708-3 0  9994
2 98615  97.4435 338.6973 0003998 289.0728 299.1526 15.16619594 59103

[fcecio]

Hello,

here Francesco from the HERMES TMTC/Ground team! Thanks for the support in searching our satellite!

I am writing because there is a little error in the baud rate communicated by @rcampana, the correct one is 25000 baud.

Thanks again,
Francesco De Cecio

[K4KDR]

Thank you for providing details on the modulation & framing for these satellites. By chance would the deframer shown below be anywhere close to what is required for these signals?

[fredy]

TLE update for Buccaneer MM

Buccaneer MM
1 98648U 00000A   25083.55370955  .00000000  00000-0  98799-4 0    01
2 98648  97.7394 338.5838 0006083  17.6570 198.9674 14.91255386    05

sites.txt (10.4 KB)
buc_083_v1.dat (2.0 KB)

[fredy]

TLE update for OTP-2

OTP-2
1 98652U          25083.61942697  .00000000  00000-0  13256-2 0    04
2 98652  97.4377 338.7632 0005879 319.2026   3.0770 15.16536758    07

otp-2_083_v1.dat (1.6 KB)
sites.txt (10.4 KB)

[K4KDR]

Very nice signals from HERMES-H1 over the Eastern U.S. centered at 1514utc.

The TLE provided above put my closest approach at 1509utc, so the actual observed signals are right at 5-minutes behind what is predicted by that TLE.

I have tried a number of CCSDS deframers but no luck decoding yet. Any help on the particulars of the framing of these signals would be much appreciated!

Note that the signals require approximately 40k of RF bandwidth and of course a larger than normal audio bandwidth to accommodate the 25k baud rate. In GQRX, that is the ‘25k’ setting.

Will advise if I find the correct settings to decode these packets!

[fcecio]

Hello, looks like a familiar footprint! While we retrieve the correct framing parameters, may I ask if you have collected a recording of the IQ samples? Are you available to share them with us?

Thanks,
Francesco on behalf of HERMES engineering team

[K4KDR]

Glad to!

Those files get terribly large. I only had -3- packets with enough SNR to decode… here is the strongest one.

The file is a 32-bit float I/Q recording from GQRX. The sample rate is 93750.

https://www.qsl.net/k/k4kdr//iq/hermes-h1/

[yuriev]

Thank you very much! Were you also able to estimate a TLE from this data?
Yuri from HERMES Payload Team

[K4KDR]

Only that the observed signals were almost exactly 5-minutes behind the TLE provided

[macphersonrss]

new gnss derived TLE for OTP-2

OTP-2
1 98652U          25083.58503016  .00026338  00000-0  13465-2 0 00002
2 98652 097.4389 338.7298 0006147 305.1455 189.4160 15.16593219000015

[yuriev]

Hi Fredy,
as you have probably read it seems “our” TLE for HERMES H1 are wrong, and the satellite has already accumulated 5 minutes of delay (at 15:09 UTC) with respect to the information we had. It is possible to check for HERMES H1 passages adding a delay of 6-7 minutes to the expected passages?
Thank you very much!
Yuri for the HERMES team

[fredy]

@K4KDR

Note that the signals require approximately 40k of RF bandwidth and of course a larger than normal audio bandwidth to accommodate the 25k baud rate. In GQRX, that is the ‘25k’ setting.

This looks like SatNOGS DB - uHETSat. Can you check if it was visible during the pass?

[fredy]

@yuriev

as you have probably read it seems “our” TLE for HERMES H1 are wrong, and the satellite has already accumulated 5 minutes of delay (at 15:09 UTC) with respect to the information we had. It is possible to check for HERMES H1 passages adding a delay of 6-7 minutes to the expected passages?

With a quick look the TLE looks good:

It is very close to the one we use, and get fair results, for the ION Deployer. @yuriev are you sure about the 5min difference?

[K4KDR]

I can only go by the prediction from the TLE that indicated my closest point should have been at 1509utc.

… but the downlink packet observed almost exactly at 401.500 MHz arrived here at 1514utc.

[yuriev]

Absolutely not unfortunately. But @K4KDR reported a 5mins delay. Also, a few seconds of difference between the ION TLE could correspond to several tens of seconds difference on HERMES (taking into account the ION to HERMES mass ratio).
We are still analyzing the packets @K4KDR sent us to verify this hypothesis

[fredy]

@K4KDR

The TLE provided above put my closest approach at 1509utc, so the actual observed signals are right at 5-minutes behind what is predicted by that TLE.

If this means at 15:14 UTC then probably is uHETSat:

[fredy]

@yuriev

Absolutely not unfortunately. But @K4KDR reported a 5mins delay. Also, a few seconds of difference between the ION TLE could correspond to several tens of seconds difference on HERMES (taking into account the ION to HERMES mass ratio).
We are still analyzing the packets @K4KDR sent us to verify this hypothesis

Indeed there is a difference in the volume/mass but, from my experience, this wouldn’t justify a difference of 5min in such a sort period after deployment, this is why I’m wondering.

Anyway, doesn’t hurt to verify any of the results, please do and let us know if you managed to get any results. Until then I think it is better to keep the current TLE.

[fredy]

@macphersonrss

new gnss derived TLE for OTP-2

Thanks! This TLE confirms more or less the TLE produced in Transporter-13 Rideshare : VSFB SLC-4E : 15 March 2025 (06:39 UTC) - #130 by fredy!

I’ll add the set in DB, however due to the older epoch, the one in the link above will be used.