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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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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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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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Would lunar flyby be less costly in delta-v than direct change from ISS to Hubble orbits

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 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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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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Calculating dV to raise apoapsis at an arbitrary point of an orbit

This is similar to another StackExchange post (right down to the Kerbal Space Program mentions), but with a different approach. The question I'm trying to solve is thus: Given current orbital state ...
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How much delta v does it take to get to the Sun-Earth Lagrange 3 point?

How much delta v does it take to get to the Sun-Earth Lagrange 3 point? Also, Would higher delta-v allow a craft to get there much quicker? Would two hohmann transfer orbits be the most efficient ...
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How can the delta-V to a specific altitude in Earth orbit be calculated?

I've seen charts and tables, etc., that list the delta-V to Low Earth Orbit as 9.3-10 km/s. But LEO could be anywhere below 2000 km. So how do I calculate the delta-V to reach a specific altitude in ...
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Optimum delta-v burn to change periapsis or apoapsis at an arbitrary point on an elliptical orbit?

This question is explicitly not about doing burns at the apoapsis or periapsis in order to raise/lower the other apsis. Of course those are going to be the most efficient maneuvers, and the burns ...
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Earth->Mars: Porkchop, departure burn and orbit inclination

My goal is to get a graph "spaceport latitude"<>"delta-v to reach mars". Using "Trajectory Optimization Tool" (Matlab one) I have successfully generated porkchop graph for Earth->Mars transfer. ...
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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 does bi-elliptic transfer compare to Low Energy transfers / Interplanetary Transfer Network?

I know this is a bit of apples-to-oranges comparison, since bi-elliptic transfer is a purely mathematical construct in a two-body problem, while ITN is a great "maze of opportunities" based on the ...
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Which orbital maneuver is currently regarded as the most viable for a human mission to mars?

I realize that there are different orbital maneuvers for different goals (e.g. optimizing time, efficiency, cost, etc.). However, which variables are currently considered as the most important to be ...
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I'm planning a roadtrip to the moon. What is going to be my best transfer orbit? How far will it be?

Fed up with clouds ruining clear nights here on earth, I point my car upwards, and head for the moon. My car can provide the same amount of relative thrust it can going 65 mph, simply in whatever ...
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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 will SES-9 reach geostationary orbit from inclined transfer orbit (from F9 2nd stage)

This spaceflightnow article says near the end that the Falcon 9 2nd stage will leave SES-9 in an elliptical, inclined transfer orbit. This article says that this is a super-synchronous orbit, and that ...
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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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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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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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How are satellites deployed into equatorial LEO?

Considering launches from the two major cosmodroms are launched into inclinations quite far from equatorial, and that inclination change in LEO is awfully expensive in terms of delta-v, what ...
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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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Saving delta-v by splitting plane changing manoeuvre?

When I was calculating what delta-v was required to transfer between two orbits of radius 1 and 2, with a relative inclination of 20 degrees, I found, as expected, that it was best to combine the ...
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Intercepting an object on flyby past Earth?

Suppose we detect an object on an orbit that will pass close to Earth, entering our SOI, but escaping after just a few days. If we wanted to mount a mission to intercept that object, how would we go ...
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What was the typical perigee after a shuttle de-orbit burn? [duplicate]

What was the typical1 (theoretical) perigee after a shuttle de-orbit burn? I say 'theoretical' given that presumably the orbiter would already have undergone further deceleration before it reaches ...
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Do all spacecrafts first enter orbit and then transfer to another body? [duplicate]

I would like to know if all spacecraft that have visited other planets first orbited our own planet and then performed an orbital transfer, or if there have been some that just went directly to the ...
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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 aerobraking be used to enter high orbit without landing?

It has been proposed that a human mission to Mars could park the transfer habitat in high Martian orbit while only a small capsule lands on the surface or on a moon. This in order to minimize the mass ...
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Soyuz TMA-18M ISS rendezvous: expedited 4-orbit vs regular 34-orbit - How does fuel usage compare?

Follow up to this question: Why will Soyuz TMA-18M take two days to reach the ISS?. Clearly the expedited rendezvous is cheaper in terms of time. However I was wondering how fuel usage compares. Is ...
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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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What are the steps between rocket launch and docking to the ISS?

This question focus on space missions docking with the ISS. On this youtube video, the process to rendez-vous with the ISS is described. If I understand correctly, it consists in taking of, place the ...
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After a trans-Mars transfer, what is the direction of the rotation of the orbit around Mars?

I'm not quite familiar with space exploration vocabulary. For the Apollo missions, the trajectory was figure-8-shaped. Thus, the direction of rotation of the Earth orbit was opposite to the one ...
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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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How could transfers between SEL1&2 and EML Lagrange points be utilized?

The Earth has 7 Lagrange points nearby since SEL1 and SEL2 (Sun-Earth Lagrange points 1 and 2, respectively) are only between 3 and 5 LD (lunar distances) away from the five EML (Earth-Moon Lagrange) ...
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How much harder is it to land on the Moon away from the equator and the poles?

If a ship enters orbit around the Moon's equator, any place on the equator is equally accessible and doesn't take long to get to. The ship passes over the same strip of land with each orbit. Equally, ...
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Prograde/retrograde vs radial/antiradial burn - why are the former so much more common?

On circular orbit burning prograde/retrograde makes the orbit elliptical with raising or lowering the orbit on the opposite side of the body, making the burn position the new periapsis/apoapsis ...
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Orbital rendezvous with low-thrust engines?

The Hohmann Transfer is clear enough; Accelerate on your (circular) orbit at the right time, raising the apoapsis until it meets the target orbit. Once there, burn again to raise the periapsis - ...
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Efficiency of Oberth maneuver depending on altitude - is getting the last few kilometers worth it?

How does efficiency of a burn of given duration change with altitude of periapsis? Am I right, that for Earth (equatorial radius 6,371km), for orbits with 100 and 200km periapsis altitude ...
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Descending into any orbit: Which requires less delta-v, a wide one, or a narrow-elliptic one?

If a vessel is to enter an orbit around some body (approaching from the "outside" fast), and can choose between a very high circular orbit and a very elongated elliptical orbit of the same apoapsis, ...
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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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Optimal turning from equatorial to polar orbit

Yeah, I know, "launch into target orbit". But let's assume we need to perform the maneuver. A satellite in LEO equatorial orbit would need excessive amounts of delta-V to enter polar orbit. The ...
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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 do upper stages spin before deploying satellites?

I saw the Ariane 6 animation, and I noticed, that the upper stage spins before deploying the satellites. Why are they doing this? Is it necessary or is it possible to successfully deploy a satellite ...
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How can I obtain the parameters related to launch of Delta 4 Medium?

I want to be able to model the entire launch mission of the spacecraft GOES-O and its Launcher, Delta 4,2 medium plus. Is it in anyway possible to obtain:- The burn profile, (simplified ones are ...
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Can I use Tsiolkovsky's rocket equation in combination with this equation for a Hohmann transfer to find what mass of propellant is needed?

I'm wondering if it's appropriate to use the two equations in order to solve for m0/m1 to find the mass of propellant needed to perform a hohmann transfer. If it isn't, can someone suggest an ...
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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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How to model a continous burn and recalculate orbit properties post burn

I've been working on this for a while with little success. I'm trying to model a continuous burn orbit maneuver for say 5 minutes. I've tried to split the burn into multiple sub-burns that are ...
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Will the International Space Station's propulsion system be changed to electric propulsion?

I know the systems being used are very new and being used in very small satellites, but if a system could be scaled up in the near future, that would certainly help keep the station afloat. Thoughts?
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What is a “Y-Thomson spin”?

I am new in the field of Spacecraft Attitude Dynamics and Control, and came across the terminology "Y-Thomson spin". What is it? Where can I read more about this attitude control mode?
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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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Could upper stages take down space debris as a 2nd mission?

Used upper stages seem to be a big contributor to space debris. Wouldn't it be fairly easy and cheap to instead have an upper stage somehow physically lock onto a big piece of space debris and push it ...