Timeline for Xenon vs Hydrazine, "Should I Stay or Should I go?" Dawn mission decisions
Current License: CC BY-SA 3.0
9 events
| when toggle format | what | by | license | comment | |
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| Oct 30, 2017 at 4:48 | comment | added | uhoh | I added a second bounty, wanted to thank you for being the first person to post an answer explaining what was going on. Lucky for you the SE interface requires each bounty to be larger than the previous one :-) | |
| Oct 30, 2017 at 4:44 | history | bounty ended | uhoh | ||
| Oct 27, 2017 at 14:50 | comment | added | uhoh | OK this is really interesting! I will watch the video and do some reading now... | |
| Oct 27, 2017 at 13:45 | history | edited | Julio | CC BY-SA 3.0 |
added 164 characters in body
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| Oct 27, 2017 at 13:42 | comment | added | Julio | I have found a nice video explaining the subject here, with a slightly different notation (the figure I posted is from my old space vehicle dynamics courses which slides are in spanish) es.coursera.org/learn/spacecraft-dynamics-kinetics/lecture/… | |
| Oct 27, 2017 at 13:40 | comment | added | Julio | Well, to maintain nadir-facing in circular orbit you need to take into account your satellite inertia assimetries. As I have studied this is the first order term when attempting attitude station keeping. A stability analysis is useful since if the system if unstable you would need to waste more control action (e.g. RCS or reaction wheels) to keep pointing. However, I also agree with you that switches between Earth-facing and nadir-facing contribute as well to lower the control budget. | |
| Oct 27, 2017 at 10:31 | comment | added | uhoh | Thanks for your answer! I had thought that the use of hydrazine was needed to switch between Earth-facing and nadir-facing orientations, or maintaining nadir-facing for a non-circular orbit, but I never stopped to think about torques directly on the spacecraft from the gravity field, so this is really helpful! Can you add a credit for this figure? Crediting original sources is always good in SE. Also if you can add a link to some place where I can read more about what $k_1, k_3 = f(I_1, I_2, I_3)$ means and maybe how to do some of the math? | |
| Oct 27, 2017 at 8:33 | review | Late answers | |||
| Oct 27, 2017 at 10:10 | |||||
| Oct 27, 2017 at 8:14 | history | answered | Julio | CC BY-SA 3.0 |