Linked Questions

7 votes
4 answers
2k views

Has ion propulsion ever been used in a deep space trajectory correction maneuver proper?

Answer(s) to What types of propulsion are used to adjust an orbit? lead me to wonder if electric propulsion has ever been used for a proper TCM or "trajectory correction maneuver" in deep ...
uhoh's user avatar
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12 votes
3 answers
1k views

Xenon vs Hydrazine, "Should I Stay or Should I go?" Dawn mission decisions

edit 2: There seems to have been some announcement/extension by NASA (20-Oct-2017), possibly this will shed more light on the issues in this question. edit 1: Several months have passed since this ...
uhoh's user avatar
  • 149k
5 votes
3 answers
837 views

Are there terms for Earth orbits with rational number multiples of 1 sidereal day?

An Earth orbit with a period of 1 sidereal day (and zero inclination) is a geosynchronous orbit, orbits slightly above and below that are supersynchronous and subsynchronous orbits, and a Molniya ...
uhoh's user avatar
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6 votes
1 answer
1k views

How can I verify my reconstructed gravity field of Ceres from spherical harmonics?

Based on @DavidHammen's very helpful answer I've made progress reconstructing the gravity field of Ceres from the Dawn radiometric data. The question there contains further information, but suffice it ...
uhoh's user avatar
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4 votes
1 answer
1k views

What (actually) is a 1:1 resonance, and is 2016 HO3 in one with the Earth?

In my question How was Earth's "quasi-satellite" 2016 HO3 "first spotted" and it's orbit determined? I link to two videos of simulations of views of 2016 HO3's orbit seen in two ...
uhoh's user avatar
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4 votes
1 answer
634 views

What factors would make station-keeping of an Areostationary Mars satellite necessary?

This answer introduced me to the word Areostationary Orbit - (hint, comes from Ares), an orbit that would remain stationary above a point on the equator of Mars. The article mentions that ...
uhoh's user avatar
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4 votes
1 answer
296 views

Under what conditions can a non-resonant satellite stay hidden from an observer on the ground?

From the perspective of someone on the ground, a satellite is usually not above the horizon all the time. But can a satellite have such an orbit that it is never above the horizon? Such orbits clearly ...
SE - stop firing the good guys's user avatar
4 votes
1 answer
389 views

Is TDRS-M (TDRS-13) where it's supposed to be?

edit: Status 2018-Jan-01 inclination still about 7 degrees, location still not listed in Wikipedia. This question got me thinking about the location of active TDRS satellites, and the newest addition ...
uhoh's user avatar
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1 vote
1 answer
159 views

What might this "NS" mean in this speculation about this Mars rover's future prospects?

The Reddit xkcd 695: apparently CERN scientists couldn't handle the sad ending contains the following image. In the 2nd to last panel of the bottom added-on row, the text looks like it says Sorry ...
uhoh's user avatar
  • 149k
1 vote
1 answer
250 views

Why are ICESAT-2 and CRYOSAT 2 both at inclinations of almost exactly 92 degrees?

The BBC's Esa and Nasa line up satellites to measure Antarctic sea-ice says: Authorisation was given on Tuesday for Europe's Cryosat-2 spacecraft to raise its orbit by just under one kilometre. This ...
uhoh's user avatar
  • 149k
2 votes
0 answers
75 views

Determining a suitable 'low orbit' for an arbitrary airless body

A while back, I asked this question here, dealing with finding a standard low orbit for a solar system body. The answer I received was mainly in the context of a body with atmosphere. This answer gave ...
Ingolifs's user avatar
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