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Questions tagged [station-keeping]

Operations done to keep a spacecraft in a particular orbit. Generally done by by thruster burns. In LEO this must be done to counteract the momentum loss to atmospheric drag. In other orbits it may be needed to maintain a planned relative position over a long period of time.

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Is this what station keeping maneuvers look like, or just glitches in data? (SOHO via Horizons)

I've been enjoying the JPL Horizons web interface and after I discovered the incredibly extensive database associated with SOHO (Solar and Heliospheric Observatory, also see sohowww.nascom.nasa.gov) ...
uhoh's user avatar
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Could JWST stay at L2 "forever"?

Using only reaction wheels powered by solar panel and the sunshield as a sail (in continuous active attitude control) to generate thrust from solar photon pressure in the desired direction, could JWST ...
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Will the ISS have electric propulsion to maintain altitude? Is there enough power for it?

In April 2014 this comment was made below the question What propulsion methods does the ISS use for station-keeping?: In November they said in three years, so perhaps late 2016. Since such claims ...
uhoh's user avatar
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Why is the US building a Lunar Orbital Platform-Gateway (LOP-G)?

An excerpt taken from the Wikipedia page on LOP-G says space-experts have criticized it: The Deep Space Gateway has received criticisms [...] for lacking a proper scientific goal. Former NASA ...
Magic Octopus Urn's user avatar
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The design of the halo orbit of the James Webb Space Telescope

As I feel a little less uncomfortable with "halo" orbits, with this question, I would like to explore the practical aspects, in particular those related to the design of the James Webb Space ...
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4 votes
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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 ...
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What propulsion methods does the ISS use for station-keeping?

The International Space Station is constantly losing orbital energy due to atmospheric drag. How does station-keeping work for the ISS? What sort of propulsion system is used to keep it in the desired ...
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Are any Earth orbits in continual shadow of the Earth?

Do any orbits around Earth leave the spacecraft in permanent shadow? If not, what is the minimum amount of time that a spacecraft must be exposed to sunlight on average?
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Can solar sail prevent orbital decay?

I can imagine a satellite with a solar sail it rolls when on the night side of Earth, then unrolls near "afternoon", propelled on each past of its "sunset side" of travel. Would such system be a ...
SF.'s user avatar
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21 votes
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Why does NASA intentionally spin space probes?

In several NASA animations of missions, I've noticed that the spacecraft is rotating while traveling in deep space. This was true of Curiosity when that video came out. Now the Juno mission ...
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James Webb telescope; limits to propellant lifetime?

There is a comprehensive article on Wikipedia on the James Webb telescope. It includes a statement regarding the operational lifetime being nominally five years and optimistically ten years. However ...
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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
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How can just making the ground broadcast stronger neutralize a zombie(sat)?

In April of 2010 the Geo-not-so-stationary satellite Galaxy-15 stopped responding to ground commands. It operates as a "bent-pipe" or Transponder system, which means - roughly speaking - it will ...
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Do operating GPS satellites ever make orbital maneuvers for station-keeping?

Since GPS satellites need to face the Earth, they might execute momentum-unloading from time to time using pairs thrusters so as to produce torque but minimal change in the orbit, but I am guessing ...
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Is JWST actually in a Lissajous orbit? What will it look like? Implications for station-keeping?

Note: for lots of great background related to this question, see lagrangian points - The design of the halo orbit of the James Webb Space Telescope - Space Exploration Stack Exchange There are ...
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Halo vs Lissajous orbit: Which station-keeping strategy to select and when?

I'm looking for a comprehensive pros and cons of the two most commonly used station-keeping types of orbits used at libration points, Lissajous and halo orbits. When would one select one over the ...
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15 votes
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Do we sufficiently understand mechanics of Lagrange point stationkeeping for EML2 rendezvous and assembly?

I've been watching some recorded videos from the April 22 - 24, 2014 Humans2Mars conference (videos and live streams, when available, are on the National Institute of Aerospace channel on Livestream), ...
TildalWave's user avatar
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Why do GPS (but not GLONASS or Beidou) satellites have increasing eccentricity over time?

When comparing GPS, Beidou, Galileo, GLONASS, and potentially other GNSS, we can see that the eccentricities of GPS spacecraft are increasing with time (i.e. apogees increasing and perigees decreasing)...
costrom's user avatar
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10 votes
1 answer
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How much "wobble" does a typical geostationary satellite experience?

Recall that geostationary satellites are placed into an orbit which is designed to stay above a fixed point on the Earth's surface. If the Earth and the satellite were both spherical cows in an ...
senshin's user avatar
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How do stable equilibrium points work in GEO? If all geosynchronous spacecraft suddenly lost stationkeeping, would most "fall into" one or the other?

The (currently unanswered) question Quantitatively, how deep are the stable equilibrium points in GEO? How much delta-v to move from one to the other? (also see comments at Delta-v to move from GEO to ...
uhoh's user avatar
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Moon orbit station-keeping delta-V budget

I am looking for examples of station-keeping delta-V budgets from lunar orbiters to verify the results of an orbital-perturbations programm that I wrote for my master thesis. Any indication on where ...
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6 votes
2 answers
426 views

What orbit would a space station need to stay in orbit for N years?

(posted before on physics stackexchange but was told to come here) I'm reading this book which has a post-apocalyptic setting. At one point you look at the earth from the view of a 1000-year-old ...
C. McCracken's user avatar
4 votes
1 answer
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How satellite orbital vacancies are determined?

Before a new satellite is launched, its desired orbital altitude, inclination is determined. Now with thousands of satellites already in orbit at different altitudes, how do we know if our desired ...
ivric's user avatar
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Do operational Starlink satellites run their ion engines at night on batteries? And if so, do they have hi/low settings?

Discussion below What is the maximum thrust of the Starlink satellites? raise the question of the Starlink communications satellites' power budget and use of their ion thruster in daylight when the ...
uhoh's user avatar
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13 votes
1 answer
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What kind of thrusters will the James Webb Space Telescope use for station keeping?

Question is fairly self-explanatory, but I couldn't find an answer on Google. I would expect ion thrusters because of their efficiency. Thanks!
Peter's user avatar
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6 votes
2 answers
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How frequent are (or will be) JWST station keeping burns at L2?

Does anyone have solid information regarding the scheduled/anticipated station keeping burns for JWST at L2? In an online video I've heard mention of 'every 21 days' which at first look seems ...
BradV's user avatar
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4 votes
1 answer
389 views

Station-keeping delta-v per year for an Earth-Moon vanilla halo orbit?

This answer reminds us that an Earth-Moon L1 or L2 vanilla1 halo orbit remaining always visible to some patch on the Moon's surface requires station-keeping. Queqiao uses such an orbit having ...
uhoh's user avatar
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4 votes
1 answer
79 views

Exoplanet orbitable in permanent umbra?

Does any planet, or Kuiper Belt Object, or exoplanet measured or surmised, orbit its star either fast enough, or slow enough and thus distantly enough to cast a long enough shadow, for a spacecraft to ...
Camille Goudeseune's user avatar
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1 answer
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What is the Distinction between DSCOVR's "engines" and "thrusters"?

I am reading this article about DSCOVR which links (ref 16) to this: DSCOVR: Mission Success for Moog Engines Over a Decade Later , about the recertification by MOOG of the MONARC 5N monopropellant ...
uhoh's user avatar
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4 votes
1 answer
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How did DSCOVR use its ten thrusters for the long burn maneuvers MCC and LOI?

From this answer to my previous DSCOVR question, and this and this and this article, it seems that DSCOVR used one or more of its ten thrusters for the long burns for mid course correction (MCC) and ...
uhoh's user avatar
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4 votes
1 answer
3k views

How much Delta-V is needed for Orbital Maintenance?

My question is aimed at understanding the how much Delta-V is needed for orbital maintenance in different orbits. Obviously, there still is some residual air resistance that decreases as the orbital ...
HardcoreBro's user avatar
3 votes
1 answer
212 views

Inclination Maneuver of GEO Satellite

I have performed inclination maneuver for GEO satellite at ascending or descending node. The inclination of the satellite is 0.05 deg. Then I performed the maneuver so the inclination change to 0....
Elisa Fitri's user avatar
1 vote
3 answers
349 views

Could a framework of mirrors static in space above the Lunar south pole illuminate a moonbase there continuously?

Edit: For clarification of what I mean with "static in space above the Lunar south pole " please see this answer from @Tom Spilker or his answer to the question Orbits that allows ...
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