Sakura APRS mission

Satellites & Observations
62

Thanks for the link, I indeed miscalculated this earlier. Indeed it looks like we have around 5-7 days. Let me explain with the right calculations:

Usually the last TLE we get from space-track.org before re-entry has around 16.25 -16.45 revolutions/day. For example this is the last TLE from Binar 2 from the same deployment at ~16.3 revs/day:

1 60957U 98067WX  24310.06998193  .09654898  12176-4  19638-2 0  9991
2 60957  51.6018 328.1298 0004329  55.5404 304.6027 **16.30458602** 12600

Below is how fast Sakura revs/day change:

1 60954U 98067WU  **24322.55240802**  .00619248  16240-3  18810-2 0  9999
2 60954  51.6222 266.8023 0009013 152.0393 208.1099 **15.91405296** 12551
1 60954U 98067WU  **24323.05467068**  .00628473  16848-3  18494-2 0  9992
2 60954  51.6215 264.1538 0009216 155.7424 204.4018 **15.92013231** 12639
1 60954U 98067WU  **24324.12129961**  .00708078  21809-3  19332-2 0  9993
2 60954  51.6217 258.5229 0009432 162.0403 198.0939 **15.93437885** 12808
1 60954U 98067WU  **24325.24954963**  .00766984  26317-3  19062-2 0  9994
2 60954  51.6200 252.5517 0009999 168.4681 191.6557 **15.95188264** 12980
1 60954U 98067WU  **24325.93838509**  .00844473  32754-3  19670-2 0  9994
2 60954  51.6187 248.8973 0010150 173.0652 187.0499 **15.96385162** 13093
1 60954U 98067WU  **24327.18945683**  .01057773  55375-3  21654-2 0  9994
2 60954  51.6187 242.2456 0010210 180.2959 179.8046 **15.98748573** 13294
1 60954U 98067WU  **24328.00159946**  .01206815  76881-3  22365-2 0  9993
2 60954  51.6181 237.9127 0010577 185.5812 174.5082 **16.00532876** 13424

You can see that for each day the revs/day are increased by ~0.015. This would mean that reaching 16.3 from the current 16.0 it would take 20 days, however the rate of change of revs/day is also increasing as we reach lower orbits, especially under 16 revs/day. So, if we take this into account then 20 days can become 5-7 days. Another significant parameter is also the space weather that can affect the re-entry time too.

I hope it start again transmitting in order to be able to track its re-entry properly. Let’s see.

3 Likes
63

CosmoGirl-Sat still has good CW beacon https://network.satnogs.org/observations/10648826/

2 Likes
64

https://x.com/CitGardens/status/1862621367310721311

image
image703×739 140 KB

3 Likes
65

It’s sad that it wasn’t beaconing at these last orbits… it would be a good opportunity for tracking it until its re-entry. Hopefully will achieve that with CosmoGirl-Sat re-entry.

3 Likes
66

Thank you for your cooperation in receiving signals from SAKURA. Although it was a short period of two and a half months, we have concluded the operation of SAKURA. Our next satellite, YOMOGI, will also be deployed soon, so we would greatly appreciate your support with it as well.
Sincerely,
Gardens SAKURA Team

8 Likes