Questions tagged [oberth-maneuver]

A powered flyby, or Oberth maneuver, describes a maneuver in which a rocket falls into a gravitational well, and then accelerates when its fall reaches maximum speed. The resulting maneuver is actually a more efficient way to gain kinetic energy than applying the same impulse outside of a gravitational well.

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Besides hyperbolic flybys, what are all the other cases where the Oberth effect can be used?

For hyperbolic and parabolic flybys it's common to take advantage of the Oberth effect and get the most delta-v from a propulsive impulse by doing it at the point of maximum velocity. Question: But ...
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Does Lightsail-2 take significant advantage of the Oberth effect?

The cubesat Lightsail-2 has been deployed and has communicated with ground stations. See The Planetary Society's LightSail 2 Healthy as Mission Team Continues Spacecraft Checkouts In the near future,...
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Mangalyaan + Trident; is it possible? escape the solar system using a low cost booster

5 years ago, India launched the Mangalyaan spacecraft to Mars, on a budget that raised eyebrows at the time. It was probably the Mars mission launched with the least powerful rocket; a feat only made ...
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Why is a Hohmann transfer from an elliptical orbit to a circular one more efficient if done from Perigee?

I was doing some calculations, mainly a Hohmann transfer between the following two orbits... Note my calculations assume 0 perigee argument, 0 inclination and 0 right ascension... Orbit start (400 ...
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Is it profitable to save fuel for the Oberth effect during a Jupiter gravity assist?

Probes to the outer Solar system use a Jupiter flyby for gravity assist, all six such missions thus far have. While flying near a gravity well one can enjoy the Oberth effect which multiplies the ...
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How close to Jupiter does a spacecraft need to get in order to gain maximum gravity assist and Oberth effect bonus for leaving the Solar System?

Given that a spacecraft's purpose is to leave the Solar System as fast as possible, how deep into Jupiter's gravity well would be optimal for an assist in the planet's orbital direction? Jupiter's max ...
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Brown dwarfs: could they be used to gain velocity in either a gravity-assisted slingshot or an Oberth maneuver? Why or why not?

Are brown dwarfs useful for gaining velocity via gravitational slingshot (or Oberth Maneuver, I'm still fuzzy on the difference to be honest) by a theoretical starship with fusion propulsion looking ...
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Has Juno now gone faster than - and braked harder than - any other human-made object ever?

Juno just passed its closest approach to Jupiter, going 58 km/s because it was so deep in Jupiter's gravity well. Ironically, it did this while retrofiring its engines, to slow down. That sounds ...
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Can the Oberth effect cause space-time distortions?

I am making the sort of rhetorical parallel between Oberth effect that I conclude applies even to light because light is actually solid of some sort photons or gravity well of Earth/Sun/galaxy, black ...
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Could friction heat from aerobraking be used to power propulsion?

Aerobraking has always been thought of as a way to economically decelerate a spacecraft before landing or orbit insertion. I'm asking here if it could instead be used to accelerate a spacecraft. ...
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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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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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Oberth is confusing me. Apparent violation of conservation of energy

Let's say we have an elliptical orbit that goes from LEO periapsis to apoapsis near Earth's Hill Sphere. You can merely nudge your satellite at the apoapsis a bit higher (a tiny burn at periapsis), ...
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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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Is the Oberth effect applicable to any speed change, or only to ejection of reaction mass?

Rocket engines provide the most efficient velocity change per mass fuel used when in periapsis because of the Oberth effect. But is this an effect of a spacecraft losing mass (exhausting it through ...
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Does the Oberth effect motivate complementing ion electric propulsion with chemical rocketry?

The solar electric ion propulsion engine of the Dawn spacecraft to Vesta and Ceres used Mars for gravity assist. Would it be gainful to complement an ion engine with a high thrust (solid) chemical ...
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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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What are the problems with using the sun for Oberth maneuvers?

Presumably, it has something to do with the sun being rather hot. All the same, are there any potential cases with current technology where swinging close by the sun would be worth the shielding for ...
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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 ...