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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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Help choosing a gravity assist scenario for this problem

The problem stated below is from an assignment I was given. My initial approach involved doing a direct Hohmann Transfer to Saturn. This approach violated the fuel constraints and hence was deemed ...
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Why does the Apollo-8 Trans-Lunar Injection burn appear to be pulsing in this photo?

This tweet called my attention to The Smithsonian National Air and Space Museum story Photographing Apollo 8's Orbit Toward the Moon. The story is quite an interesting bit of space history and worth a ...
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What is the closest intentional separation achieved by two satellites?

I would like to know what is the closest separation achieved by two satellites. Let's restrict it to Non experimental satellites (or else it would be 0) Operational satellites (no collision) Post ...
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How do long range space probes adjust trajectory?

More specifically, after the main launch adjustments have been made using the primary boosters and temporary adjusting propellants how might even the slightest trajectory and orientation corrections ...
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How does SpaceX's Dragon get to the ISS?

How does SpaceX's Dragon capsule get to the ISS? Does Dragon use the onboard Draco thrusters in order to raise its orbit to the station or does the second stage of the Falcon 9 perform the majority of ...
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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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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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Is the analysis of this maneuver correct?

Can someone out there help explain (guide, give examples etc.), or show a solution of, the following textbook problem that I can't manage to solve? You’ve just completed an analysis of where the ...
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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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How often has 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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Which engine worked the hardest to keep the ISS in orbit?

The ISS has spent two decades fighting drag caused by its large size and huge solar panels pushing through the tail-end of Earth's atmosphere only a few hundred kilometers above its surface. Question:...
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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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Injection versus insertion

I've noticed that maneuvers to leave a body's sphere of influence on the way to another body are invariably referred to as injection maneuvers, for instance, translunar injection, while maneuvers to ...
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What are the practical uses of a state transition matrix?

I am studying different dynamical models of relative motion of satellites. In my work, I've always just used a numerical integrator like RK78 to integrate the cartesian system of equations: $\dot{r}=...
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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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Proper handling of terminal guidance of finite burn closed-loop execution for rendezvous conditions?

I'm writing some software which uses Optimal Control Theory / Calculus of Variations / Pontrayagin's Minimum Principle / Primer Vector Theory to do closed-loop execution of finite burns (in KSP). ...
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What orbital maneuver(s) did the SOHO have to execute for halo orbit insertion?

I started, but did not complete, Classical Mechanics as an undergraduate, decades ago so I will not understand a highly technical answer. I am writing a novel where an astronaut needs to execute HOI (...
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Is it possible to supply 47 tons of payload to the orbit with 5 tons of fuel?

There are 2 orbits: Circular orbit with 200km altitude Circular orbit with 800km altitude The space tug is already on the first orbit. Its dry mass is 960kg, the total mass of fuel is 5250 kg. It ...
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Optimal transfer between to identical orbits with different RAAN

Two orbits are given with the identical orbital elements, despite the RAAN, which differs by 90 degrees. The inclination is 80 deg, AOP is 310 deg, apogee is on 10000km, perigee on 1000km altitude. ...
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Multiple revolution Lambert problem

The Lambert problem solution determines the $\Delta V$ required to transfer from r1 to r2 in ...
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148 views

Is it OK to spend 3 tons of fuel for the orbit transfer?

There are 2 coplanar orbits (same $i$,$\Omega$,$\omega$): Apogee and perigee on 200km Perigee on 700km, apogee on 8000 km I used the izzo.lambert function from ...
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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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Difference between approach maneuvers to the insertion points of halo and Lissajous orbit?

I have read that spacecraft use two mid-course corrections to approach the Lagrange point, then do a final orbital insertion maneuver to enter into a halo orbit. Are there any specifics about this ...
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What are common guidance strategies for a finite orbital maneuver?

Suppose we have our spacecraft in a circular orbit around the Moon and we want to transfer it to an elliptic orbit with a medium-thrust (10-100N) retrograde burn. Based on the current state estimate, ...
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Will an array of multiple ion engines still be more efficient than a single chemical engine?

I was just thinking the other day and got this idea out of my head. I'm not an aerospace expert or anything even close to it, so please understand even if this turns out to be a really basic question: ...
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How to match orbital speeds of 2 or more satellites in different orbits?

Satellite ME is orbit around the Moon and Earth. Satellites E is around Earth. I understand the low orbit satellites orbit at higher speeds. Can Sat ME match the speed of any of Satellites E at any ...
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Maneuver to the optimal point of a given orbit

There is a spacecraft on an initial orbit. There is a target orbit. The Keplerian elements are given for the orbits. The problem is: when and what $\Delta V$ to apply to the SC to move it to the ...
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Meteosat 11 big deboost/reboost

Before Feb 2018, the meteosat 11 (MSG-4) were periodically reboosted approximately every 85 days: EDIT: added the orbital inclination plot to show the clearly visible variation to both semi-major ...
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Was the gravity turn used in early spaceflight?

Reading through the Wikipedia article about Gravity Turn, specifically the Use in spaceflight section, it seems that the Gravity Turn was not used in early spaceflight. Is that correct? For example, ...
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Piggybacking to Enceladus

The latest NASA New Frontiers selection did not select any finalist proposals to Enceladus, which is one of the most promising targets for life in the solar system. It did however select Dragonfly, ...
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Delta-v obtained from Titan by the Cassini spacecraft; just how much of a “gas tank” was it?

In the video Cassini at Titan: A World Unveiled after about 01:56 Linda Spilker, Cassini Project Scientist, Jet Propulsion Laboratory says: Not only was Titan ...
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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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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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How is a Russian satellite's behavior “very abnormal”?

The BBC has a news article saying: "Mystery Russian satellite's behaviour raises alarm in US". But the article doesn't say how or why the behavior is "abnormal". And the linked transcript of Remarks ...
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Can the Sun's magnetic field be used to propel a solar satellite?

Can diamagnetic materials or a diamagnetic devise be used to propel using the magnetic field of the Sun in a solar polar magnetic assisted slingshot?
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Can someone give me a 'trajectory optimisation for dummies' answer?

So, I am currently doing a project on trajectory optimisation. I get the principle of it, minimise fuel cost for a journey, or try to maximise the spacecraft weight at target destination, and that ...
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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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What are “Ohms burns” in the context of Scott Kelly, KSP, and the Space Shuttle?

The Ars Technica video Astronaut Scott Kelly teaches orbital mechanics with Kerbal Space Program (also in YouTube) is a little bit humorous. When Scott Kelley is talking about orbit circularization ...
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How do multiple satellites deployed in the same launch reach their different final orbits?

For example on the Iridium-4 launch from SpaceX on 22-12-2017, 10 satellites are deployed almost at the same time. How do the satellites go into their own separate orbits after they are deployed? When ...
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How rare is it in the 21st century to use five stages to get to LEO, especially for a low-mass payload?

@BobJacobsen's comment about the MX Missile (and protests) in the 1980's got me clicking in Wikipedia, which led me to the Minotaur IV launches, the most recent of which seems to be ORS-5 or "...
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Was anything special done for the Cygnus OA-9 launch to give it so much extra fuel?

The Cygnus OA-9 mission has had plenty of extra fuel to burn! While docked at the ISS, it burned for a while to raise the ISS' orbit. This may have been more of a demonstration and token altitude ...
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How to calculate thruster force calculation during maneuvers

I'm working in a satellite operator company, operating a GEO cubic shaped satellite, with 16 chemical thrusters and 3 reaction wheel for attitude control maneuvering. We have vendor provided flight ...
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What is Tiangong-2 doing?

Some news in various outlets following some twitterings including this tweet by Jonathan McDowell about Tiangong-2 performing a sizeable orbit-lowering, followed by a re-raising: ‏ OK now that's ...
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Largest delta-v 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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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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Orbital change to reach specific earthly location with constrained dV

If I have an orbit (in this case, a non-eccentric orbit) and, at a specific point in time, need to find a maneuver to cause reentry in a specific point as quickly as possible with a delta-V limit (if ...
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Can/Will the James Webb Telescope maintain its position passively?

A recent article about the telescope states (emphasis mine): Unlike Hubble, which orbits the Earth at about 340 miles of altitude, Webb will be sent almost a million miles into space, at a ...
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Improvements to script for Finite Burn Trajectory Optimization with MATLAB

I've written a MATLAB script to use the bvp4c two point boundary equation solver to implement a Calculus of Variations trajectory optimization of the problem of a single finite burn with a free coast ...
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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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Space model transfer to moon displacement [closed]

I'm having a problem with the insertion from a LEO orbit into a moon orbit/ moon flyby in my gravity simulator. I use the calculations listed below. I think it is due to the fact that the moon pulls ...