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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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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 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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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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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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When the ISS moves, do the astronauts feel it?

The ISS has thrusters to avoid debris and to combat orbital decay. Do the astronauts feel the station moving? Do they have to hold onto something and it is the same for when they rotate the station ...
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Could a partial space elevator be practical and useful?

Would it be technologically and economically practical to build and operate a space elevator that only provided transport between lower and higher orbital paths? Such a mechanism would only avoid ...
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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 are flight plans calculated?

When a project like Rosetta is being developed, how are flight plans calculated? Do planners simply input the desired target into a program or a flight computer which spits out the optimum flight path ...
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How does a spacecraft know that it is in orbit?

After a 5 year long journey in space, Juno finally reached and started orbiting Jupiter. How does the probe actually know that it is in orbit, so that it can send confirmation message like 'Welcome 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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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 ...
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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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What prompted Lovell on Apollo 8 to announce “there is a Santa Claus”?

On Apollo 8, following the first trans-Earth injection, when the crew came back into contact with Houston, Lovell said: "Please be informed there is a Santa Claus." (Transcript) Given that Apollo 8 ...
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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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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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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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Was SpaceX's launch of Formosat-5 more vertical than normal for any particular reason?

Reading both the abstract and the plain language summary of the recent paper published in the journal Space Weather Gigantic Circular Shock Acoustic Waves in the Ionosphere Triggered by the Launch of ...
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Does a mission to Venus orbit require less propellant than a similar mission to Mars?

Gravitational attraction is determined using G (m1m2)/r^2 Which indicates the force is inversely proportional to the square of separation of the bodies Of the terrestrial planets Mercury, Venus, ...
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What range of orbital elements was available for the Space Shuttle?

What range of orbital elements (inclination, apogee, eccenticity) was available for the space shuttle? What range has it really achieved? What were the engineered limits?
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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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How does the gravity of a massive non-spherical object act on things around it?

Firstly, not sure if this question ought to be in the physics SE site. Please let me know if it should. Secondly, I don't know a whole lot about physics (I'm just inquisitive). So please try to keep ...
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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 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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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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Transfer between elliptical orbits

For circular orbits the most efficient transfer is achieved with a hohmann transfer or a bi-elliptic transfer. But what is the most efficient way to transfer between elliptical orbits? I assume in ...
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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 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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Are there any remaining spacecraft that can retrieve objects from Earth orbit?

Now that the Space Shuttle has been retired, are there any spacecraft available that can retrieve an object from orbit and return it safely to Earth? What would be the maximum size of such an object?
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How much adjustment of position is required when making long flights through the solar system?

It is hard enough to exactly aim a rocket when you know all the forces on it, but on a long journey there must be any number of minor gravitational attractions to rocks and other mass in space, and ...
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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 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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Mars Orbit Upon Intercept

I'm running a numerical simulation that calculates an interplanetary trajectory from Earth to Mars, and I'm trying to get a spacecraft into an orbit about Mars upon intercept, but am having a little ...
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Cause of ISRO MOM's LAM shutdown during the 4th orbit raising manoeuvre

The 4th orbit raising manoeuvre of ISRO's Mars probe (MOM or Mars Orbiter Mission, informally called Mangalyaan) did not go as planned, as the LAM (Liquid Apogee Motor) shut down prematurely. ...
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Is a braking maneuver more effective at periapsis?

Although my asking this question now was inspired by this one, it's a question that's occurred to me before in the context of orbital capturing. Another way to put this might be: is there an ...
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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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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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What is the flight plan to get Gaia in orbit around the Sun–Earth $L_2$ Lagrangian point?

Gaia is a planned European Space Agency's (ESA) space observatory that will aim to chart a three-dimensional map of our Galaxy, the Milky Way. It is planned to operate around the Sun–Earth $L_2$ (SEL2)...
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Oberth Effect for non-tangential acceleration

Due to the Oberth Effect, it is most efficient to accelerate a spacecraft along its orbit at or as close-as-possible-to periapsis, and decelerate within close proximity to apoapsis. But all ...
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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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Coordination of RCS on Apollo CSM/LM

The RCS thrusters on the Apollo Service Module were positioned approximately around the center of mass of the ship, such that translational maneuvers wouldn't unnecessarily rotate the ship. While the ...
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How many orbits will it take for Santa to deliver all the presents?

This year Santa has decided to try a new strategy to deliver presents which he hopes will require less physics-defying magic, since magic is in short supply these days. Instead of personally flying ...
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Where could you go in a 20km iron asteroid?

We know from this question that an asteroid 20 km in diameter is feasible as a hollow space habitat. There are many variables in real life, but assuming you had a spherical solid iron asteroid 20 km ...
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What creative orbital maneuvers might I do to save fuel for a geosynchronous spacecraft?

I've heard that there might be some creative ways to get to Geosynchronous Orbit that could save a lot of fuel. How might I manage to make this happen?
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Why are orbit raising maneuvers for Mangalyaan done in the early hours?

I was reading this news article, and it was mentioned that orbit raising is done in early hours. In all the five orbit raising operations, they are raising them only during night. What could be 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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Differences between launch injection and transfer orbits for geostationary satellites

I am familiar with all different orbits but I struggle with the new launch injection method in GTO. What are the differences between sub-synchronous and super-synchronous transfer orbits compared to ...
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Are transfers between two orbits commutative?

Are the propellant mass and transfer time from orbit A to orbit B the same as from orbit B to orbit A, considering low-thrust propulsion? That is, in the case of dealing with Keplerian orbit ...
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Why rotate the Falcon 9 2nd stage after deployment?

Towards the end of the JCSAT-14 live webcast, after the satellite was deployed, we could see small thrusters firing on the second stage, starting to rotate it: The webcast ended shortly afterwards, ...
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How are retrograde orbits attained?

If a satellite is to be inserted into a retrograde orbit (opposite to Earth rotation direction) is it accelerated straight in the desired "westwards" direction until (after overcoming Earth rotation ...