Questions tagged [orbital-maneuver]

In spaceflight, an orbital maneuver is the use of propulsion systems to change the orbit of a spacecraft.

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How could a 90 m/s delta-v be enough to commit the space shuttle to landing?

Wikipedia claims (although with no citation) that in order to make the space shuttle land, an initial powered delta-v of 322 km/h was applied in orbit, retrograde to the shuttle's orbit. 322 km/h is ...
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How can I intuitively understand gravity assists?

For example: How should a spacecraft pass the Moon to reach escape velocity from Earth? How should it pass Venus for a slingshot towards Jupiter orbit? Conversely, to descend Venus to Mercury? Is ...
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How often does ISS require re-boosting to higher orbit?

I know that ISS, being in low Earth orbit, requires regular boosts. But I can't seem to find information on how often does this happen. Is it done during each resupply mission, only during some of ...
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What happens to JWST after it runs out of propellant?

JWST will be orbiting L2 which is unstable equilibrium thus will require propellant for station keeping. JWST will carry propellant for 5-10 years. What will happen once it runs out of propellant? ...
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Why should space probes have to orbit the Earth before being launched at other planets?

I'm curious to know why any satellites that need to be sent to other planets should be moving around the Earth rather than directly going towards their destination? Today, India launched one satellite ...
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Unravelling Cassini's “ball of yarn” orbit around Saturn, tabulation of propulsive maneuvers?

The cool GIF on the NASA JPL Cassini resources page All Orbits (2004-2017): The Ball of Yarn is quite beautiful to look at, but it also hints at some beautiful engineering and orbital mechanics as ...
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JPL Horizons original reference orbit data for Juno - how to retrieve now that it's been updated?

Because of the slow helium valve responses, Juno was not instructed to execute the large delta-v maneuver to drop from the ~53 day orbit to the ~14 day orbit originally scheduled for 2016-Oct-19. I'd ...
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Can you tack against the sun using a solar sail?

Solar sails are a great, inexpensive way to move out from the sun, if you’re not in a hurry. Ocean going ships are able to tack against the wind, and to move up wind. Could a solar sail gain inbound (...
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How would a Jupiter flyby have helped to get to the Sun? Why was it later ruled out?

The quote below surprised me. What were the orbital mechanical details of using a Jupiter flyby to get a probe from Earth so close to the Sun? Was a "U-turn" possible; single flyby of Jupiter into a ...
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1answer
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Why would a slow spiral from a C3 of zero take about 2.4 times as much ΔV as an impulsive maneuver?

I just read a fascinating comment that I don't understand. In part it says ...the Oberth effect does not depend on the mass of the object. A slow spiral in to a low orbit from a C3 of zero will ...
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How is space assigned for satellites that follow intersecting orbits?

Assigning slots to different satellites in various polar orbits seems very difficult on account of them passing over the North Pole. This loose intersection seems like the place where mission errors ...
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Spiraling out from circular orbit to escape via low thrust, what is γ (gamma)?

@MarkAdler's comment led me to ask Why would a slow spiral from a C3 of zero take about 2.4 times as much ΔV as an impulsive maneuver? which resulted in this tidy and efficient @MarkAdler answer which ...
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Why does TDRS 1's inclination evolve so much differently than that of all the others starting in 1995?

The plot below is from the question Why do the geosynchronous TDRS satellites have this distribution of inclinations?, and the explanation says Inclination and mean motion (rev/day) for TDRS ...
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Could Earth-lunar flybys be repeated consecutively without the use of propellant?

Ever since a recent orbital mechanics question, lunar flybys have been nagging me in the sense that there is obviously energy available in the system. I'm interested if you could get a repeatable ...
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Why would Juno's originally planned orbit lowering partially mitigate radiation damage?

I'm trying to understand where Juno will pick up most of the slow, cumulative radiation damage within it's orbit. Currently it is in the higher, 53 day orbit. The original plan was that tomorrow (...
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Can someone help Scott Manley explain this Snoopy-capturing maneuver?

In his recent video Apollo 10's Lunar Module Snoopy Is Lost In Space - Could We Bring it Home? Scott Manley uses some fancy supplemental techniques in KSP to simulate and explain a possible mission to ...
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Delta-V chart mathematics

Could someone explain me the mathematics behind the Delta-V charts one can find on internet such as:                 &...
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When the ISS accelerates, do the astronauts feel it?

The ISS has thrusters to avoid debris and to combat orbital decay. Do the astronauts feel the station accelerating? Do they have to hold onto something and is it the same when they rotate the station ...
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Can I get higher with Space Junk?

There is a whole bunch of space junk; Wikipedia says there are about 19,000 pieces of junk being tracked. With no clouds, solar energy is readily available, so the biggest missing ingredient for ...
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Why did the recent Sirius FM6 launch use such a high inclination?

Earlier today a Proton-M rocket took off, carrying a Sirius FM6 satellite radio payload destined for geosynchronous orbit. Nothing super exciting, Briz-M upper stage for transfer burns and then the ...
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Is a lunar Sun-synchronous orbit possible at the “frozen” inclination of 86°?

I have been considering if it would be possible to place a satellite in a Sun-synchronous orbit in one of the lunar frozen orbits at 86°. According to NASA scientists there are four inclinations for ...
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Is 45 km unusually close to pass the ISS and deploy a microsatellite without warning?

Eight years ago, on September 27, 2008, the Shenzhou-7 carying three taikonauts deployed the microsatellite Banxing-1 for testing maneuvers and external imaging. A few hours later at 15:07 UTC the ...
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What is the delta-v required to get a mass in Earth orbit into the sun using a SINGLE transfer?

I've seen this several related questions to this, but they tend to focus on complex maneuvers to minimize the delta-V. If I wanted to mass-drive, railgun or tether-spin a mass so that it would ...
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Design of an elliptical transfer orbit

I was working an example in Charles Brown's "Elements of Spacecraft Design" but I can not figure out how the Time of Flight was calculated. Here is the problem Example 6.5. I got the correct answer ...
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Would lunar flyby be less costly in delta-v than direct change from ISS's to Hubble's orbit?

The question Has anything ever executed an orbit change such as between ISS and Hubble? has a in interesting answer. It made me wonder, would something like the (patented) Lunar Flyby technique use ...
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Is this really Rosetta's orbit around 67P?

From this link I fount the following representation of Rosetta's orbit relative to 67P: A video from ESA depicts a similar orbit. My questions are: is that really the relative orbit? If yes: why ...
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Oberth effect for Earth vehicles

I don't understand this and must ask a probably very stoopid question here: The Oberth effect says that a rocket is much more efficient when (and in the orbital direction of) a payload when it ...
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How to intuitively explain that reaching geostationary orbits consume more Delta V than escape orbits?

Studying again orbital maneuvers, I found the following plotting the cost of a Hohmman transfer between coplanar circular orbits (black line), in terms of $\Delta V$ against the orbit ratio $r_f/r_i$. ...
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Is Cassini's 183rd burn; some kind of engine record?

I've just read that when Cassini makes its first close pass of Saturn's F-ring on December 4, it will be the 183rd engine burn which sounds like a lot for orbital maneuvers using a spacecraft's main ...
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Quantitatively, how deep are the stable equilibrium points in GEO? How much delta-v to move from one to the other?

This answer discusses a spacecraft in GEO using a two-impulse (circular → elliptical → circular) raise & lower maneuver to move (phase) itself by 180 degrees in longitude then return to synchrony. ...
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Could Phobos be brought closer to Mars?

Because Phobos has always the same face turned toward Mars, an electric propulsion system could be placed there to slow down the orbital speed. But what would be the energy needed to supply the force ...
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ISS location identification; estimate size and direction of astronaut acceleration puzzler

note: This question addresses the same video and phenomenon described in this answer (which I found after posting this) but here I'm asking for an analysis of the trajectories of the test masses (the ...
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Was Hagoromo's capture into lunar orbit ballistic capture or more propulsive?

Hagoromo was a ~36cm nano satellite that was deployed by Hiten while Hiten was in a highly elliptical orbit around the earth, in 1990. From there, Hagoromo was able to enter into an orbit around the ...
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Is the ideal transfer between two arbitrary planar orbits always a bi-tangential ellipse?

I was reading Hollister David's short paper on bi-tangential transfers. The example he uses is a transfer between a planar circular and an elliptical orbit. I am wondering: Is an ideal, that is, the ...
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How to calculate delta-v required for a planet-to-planet Hohmann transfer?

How do you calculate the delta-v required to do a Hohmann transfer from a circular orbit around one body to a circular orbit around another? I'm assuming you'd need to know the masses of the two ...
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How do orbital boosts affect the structural integrity of the ISS?

I've become curious of this question since my time on KSP, and searches have not rendered much. In the simulator, building large stations even without the micro atmosphere being simulated, can cause ...
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How will the ion thruster powered Dawn spacecraft enter orbit around Ceres?

How is it possible for a ion thruster powered spacecraft like Dawn to decelerate to orbit Ceres? Does it have a secondary engine to accomplish this task?
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Insight mission broken-plane maneuver needed?

Will the Insight cruise stage do a broken-plane maneuver at TCM-2 (or 3), or does the Centaur upper stage have plenty of performance (as I suspect) to directly insert this small s/c into the necessary ...
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What will be “unique” about upcoming SES-9 GTO transfer profile by SpaceX?

In the SES-9 mission press kit, SpaceX mentions: "Given this mission’s unique GTO profile, a successful landing is not expected." What is considered "unique" about this transfer orbit's profile? ...
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Can solid rockets be used for flexible burn time by jettisoning them?

Solid rockets have some advantages such as high thrust (good for using the Oberth effect), storability and reliability. The main problem is that they fire all their fuel once in one set way. But ...
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What is the highest velocity a spacecraft has left Earth?

The comment below @TomSpilker's answer I'd love to see anything in LEO that can impart 20.89km/s of delta V to anything. got me wondering what the highest velocity a spacecraft has left the Earth,...
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Why would Cassini need to reach 64 degrees inclination before “threading the needle”?

The NY Times article Cassini’s Final Mission: Obliteration says that the Cassini spacecraft will end it's more than a decade long exploration of the Saturn system by raising the inclination of its ...
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Delta-v to move from GEO to GEO

To move a satellite in geostationary orbit, 166°55′E, to the antipode, 13° 4' 3.2" W, what delta-V would be needed for this to be accomplished? As for time constraints, I do not know what are the ...
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CZ-5 plus YZ-2 put SJ-17 in GEO - third stage or separate spacecraft?

CZ-5 = Long March 5 YZ-2 = Yuanzheng 2 SJ-17 = Shijian 17 Gunter's Space Page says: SJ 17 (Shijian 17) is a Chinese experimental satellite flown on the maiden CZ-5/YZ2 launch. It is ...
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Lambert's problem solution: optimal transfer time

I'm solving the Lambert's problem, and already have written a program, which solves the BVP using Shooting method and computes ...
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What is the largest delta-v ever produced in space from mechanically stored energy?

The math behind this answer suggests that while the delta-v delivered from hand-throwing an object from the ISS would not produce prompt de-orbit and atmospheric reentry, it would still lower the ...
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How often has (or how common is it for) the ISS's orbit been propulsive lowered intentionally?

The question Which engine worked the hardest to keep the ISS in orbit? laments the tireless efforts to keep the ISS from falling from the sky by regularly executing propulsive orbit-raising maneuvers. ...
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Cassini: difference between trajectory and orbital trim maneuvers in this list?

I found this site with quite a substantial amount of data, tabulations, and more for many space exploration missions. There are detailed information on the Cassini mission here: http://www.dmuller....
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What inclination change could the 5th stage Orion 38 motor provide ORS-5 (SensorSat)?

The screen shot and block quote below are from Oribal ATK's Mission Update: Minotaur IV ORS-5 Launch. ORS-5 or "SensorSat" is a technology demonstration for a class of satellites that will sit in LEO ...
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How did NASA Conclude that the General Theory of Relativity was not Needed for Earth-Moon Flight Path Computation?

This question is wholly seeking historical evidence and not about physics. It is a follow on from the Physics Stack Exchange question: Could we send a rocket to the Moon without knowledge of general ...