Saving Spinny
Guardians of the…
We've lost control of our spacecraft, Spinny, and it no longer points its directional antenna at our ground stations. You'll need to account for the spacecraft spin rates, as well as its orbit to upload the correct command sequence from ground stations around the world. In order to stop spinning, you'll need to send the following commands in the correct order:
CMD1: "PLEASE"
CMD2: "STOP"
CMD3: "SPINNING!"
Due to Spinny's limited radio capabilities, it requires contact windows of at least 3 minutes and can only receive one word at a time. The spacecraft antenna must be pointed within 45 degrees of a ground station to receive. Since you cannot point the spacececraft, you will have to predict when it will be pointed at a ground station based on a known initial pointing vector and constant body spin rates.
Constant spacecraft body spin rate of [0.1,0.1,0.1] deg/s in XYZ
Initial spacecraft antenna pointing direction of [1,0,0] in the J2000 frame at the TLE epoch (2021-06-26 00:00:00 UTC)
Commands are queued at ground stations using the following format:
SYNTAX: YYYY-MM-DD-hh:mm:ss-UTC STATION CMD SAT CMD_WORD
EXAMPLES:
2021-06-26-01:00:00-UTC BANGALOR CMD SPINNY PLEASE
2021-06-26-02:00:00-UTC GRIMSTAD CMD SPINNY STOP
2021-06-26-03:00:00-UTC SVALBARD CMD SPINNY SPINNING!
Spinny's TLE is:
Spinny
1 75001F 21750A 21177.00000000 .00000000 00000-0 00000-0 0 51
2 75001 98.0875 274.0660 0000000 0.0000 359.9920 14.57890000 1100
Ground stations are located at (WGS-84):
| Name | Latitude (deg) | Longitude (deg) | Altitude (m) |
|---|---|---|---|
| BANGALOR | 13.0344 | 77.5116 | 823 |
| GRIMSTAD | 58.33 | 8.35 | 211 |
| SVALBARD | 78.2307 | 15.3897 | 497 |
| TROLLSAT | -72.0117 | 2.53838 | 1400 |
| TROMSO | 69.6625 | 18.9408 | 134 |
Correctly queue commands at the ground stations over 12 hours to rescue Spinny and get the flag.
Solution Statistics
| observations | 138 |
|---|---|
| solves | 23 |
| points | 146 |
| average solve seconds | 9500 seconds, or about 3 hours |
| stddev solve time | 5361 seconds, or about 1 hour |
Solutions Over Time
| by time | solve count | solve percent |
|---|---|---|
| 2021-06-27 15:00:00 UTC | 1 | 4% |
| 2021-06-27 16:00:00 UTC | 7 | 30% |
| 2021-06-27 17:00:00 UTC | 14 | 60% |
| 2021-06-27 18:00:00 UTC | 16 | 69% |
| 2021-06-27 19:00:00 UTC | 19 | 82% |
| 2021-06-27 20:00:00 UTC | 23 | 100% |
solving teams:
solved by 23 teams
| team | solved at | it took |
|---|---|---|
| PPP | 2021-06-27 14:31:52 UTC | 1648 seconds, or 0.46 hours |
| DiceGang | 2021-06-27 15:00:43 UTC | 3191 seconds, or 0.89 hours |
| Tea MSG | 2021-06-27 15:48:09 UTC | 5841 seconds, or 1.62 hours |
| Visions_of_Grandeur | 2021-06-27 15:50:31 UTC | 5358 seconds, or 1.49 hours |
| Skynet Assassins | 2021-06-27 15:57:10 UTC | 6454 seconds, or 1.79 hours |
| FluxRepeatRocket | 2021-06-27 15:58:18 UTC | 6627 seconds, or 1.84 hours |
| perfect blue | 2021-06-27 15:59:36 UTC | 5336 seconds, or 1.48 hours |
| ADDVulcan | 2021-06-27 16:19:34 UTC | 7919 seconds, or 2.2 hours |
| Poland Can Into Space | 2021-06-27 16:31:23 UTC | 8852 seconds, or 2.46 hours |
| ENOFLAG | 2021-06-27 16:31:31 UTC | 7578 seconds, or 2.11 hours |
| SingleEventUpset | 2021-06-27 16:31:56 UTC | 8514 seconds, or 2.36 hours |
| OneSmallHackForMan | 2021-06-27 16:33:39 UTC | 8870 seconds, or 2.46 hours |
| NSL | 2021-06-27 16:35:48 UTC | 7523 seconds, or 2.09 hours |
| KIRBY | 2021-06-27 16:54:27 UTC | 9330 seconds, or 2.59 hours |
| Chanterelle | 2021-06-27 17:32:33 UTC | 233 seconds, or 0.06 hours |
| Solar Wine | 2021-06-27 17:39:05 UTC | 12467 seconds, or 3.46 hours |
| 1064CBread | 2021-06-27 18:01:32 UTC | 11849 seconds, or 3.29 hours |
| WeightedCompanionCube | 2021-06-27 18:13:17 UTC | 14503 seconds, or 4.03 hours |
| vMag | 2021-06-27 18:23:45 UTC | 14324 seconds, or 3.98 hours |
| UntamedFriesians | 2021-06-27 19:48:17 UTC | 15510 seconds, or 4.31 hours |
| WeltALLES! | 2021-06-27 19:53:29 UTC | 19605 seconds, or 5.45 hours |
| BLÅHAJ | 2021-06-27 19:56:41 UTC | 20136 seconds, or 5.59 hours |
| 📡🐺🔥🔥🔥 | 2021-06-27 19:59:10 UTC | 16819 seconds, or 4.67 hours |