Questions tagged [gravity-assist]

Questions regarding the use of an object's gravity to change the velocity of a spaceship.

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Gravity assist braking from Titania

If a probe entered a highly elliptical orbit around Uranus after firing its engine (similar to what Cassini did at Saturn), could it use Uranus' moon Titania as a gravity assist to circularize its ...
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If Cassini's final flyby of Saturn's moon Titan is the 127th Titan flyby, why is it called “T-126”?

Cassini's final flyby of Titan in April 2017 sealed it's fate in September of that year. This is described further in answers to What force is bringing Cassini down into Saturn's atmosphere in another ...
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Can a satellite utilize gravity gradient stabilization, solar power, electrodynamic tethering and dynamic quadrupole momentum at once?

Have any analysis been done using 2 or more devises above to function as a satellite where 1 alone would not to maintain orbit without propellants? Will this system or one with a different ...
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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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What would the perihelion of Ulysses's orbit have been without a trajectory adjustment after its Jupiter swingby?

I'm wondering what the perihelion of the orbit of Ulysses spacecraft would have been had a trajectory adjustment after its Jupiter swingby not taken place? On Wikipedia it says "The size and shape of ...
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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 you use magnets to travel through space?

My thought process is that there is very little friction in space minus gravitational pull. Which could be a good thing if you wanted to go faster or slow down. The question is, is it possible to ...
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How can I look for the best date of launch for gravity assist?

I am new to astrodynamics, and I am trying to learn about gravity assists, but I don't understand how I can easily decide a launch date and arrival late for the planet in which I calculate the gravity ...
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Is it possible to dock with a ship that is on a Galileo-like trajectory?

Reading about missions that have made or will make heavy use of gravity assist (Galileo, Cassini, MESSENGER, BepiColombo...) made me wonder about what if a heavy unmanned ship (BFS?), with all the ...
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Calculating spacecraft thrust manoeuvres with JPL data

I've recently programmed an animated simulation of the main elements (core planets and Sun) of our solar system: by using the initial coordinates from the JPL (Jet Propulsion Laboratory - NASA) ...
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Could Starman get ejected from the Solar System?

This is not about a prediction of Starman's fate, although it might be interesting to find it so. This is about any object having similar aphelion and perihelion values to Starman (Elon Musk's Tesla ...
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Can we set up an orbiting transporter between Earth and the Moon?

I will give an example with the moon. If some spacecraft is put either in orbit around both earth and moon or in highly eccentric orbit that intersects with the moon orbit, some other spacecraft can ...
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Can we speed up spacecraft to suitable interstellar travel speed using oscillating gravity assists on planets on opposite sides of the solar system?

I recently calculated using $E = 0.5mv^2$ that one kilogram of mass traveling at one tenth of the speed of light would have a kinetic energy of 449.4 trillion joules. Relativistic effects are ...
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Estimate of effectiveness of gravity turn compared to vertical flight

How much higher is a rocket following a gravity turn going to be able to reach compared to a rocket following a vertical flight ? I understand that it depends on which type of rocket and which type ...
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How much longer would New Horizons take to reach Pluto without the Jupiter slingshot?

A recent answer by PearsonArtPhoto claims: New Horizons was launched at Solar System Escape Velocity, meaning it could have visited anywhere beyond Earth without stopping. It did visit Jupiter, ...
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Would it be possible to go beyond Jupiter without making any slingshot?

It is said that we do not have such advanced technology in order to send a spacecraft out of the solar system. (Source: Everyone around) When a spacecraft is launched from Earth and aims to leave the ...
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How do we come up with the gravity assist (or slingshot) formula?

When you search up in google gravity assist formula, it comes up with the simplest version: Which means that: Final velocity = Initial velocity + 2 (velocity of the planet) Then if we do some more ...
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Does a Titan flyby guarantee that a spacecraft can escape Saturn?

Could a spacecraft orbiting Saturn, like Cassini, use a Titan gravity assist to leave the Saturn system (e.g. to bring a sample back to Earth), without using fuel other than to reach Titan?
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When are there launch windows to Neptune via Jupiter?

I suppose there's a launch window to Neptune by using Jupiter as often as there are Jupiter/Neptune conjunctions, every 13½ years. But which years are Jupiter and Neptune best aligned for gravity ...
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How to gain speed in space?

New concept: What about if we are to depend from external forces? So we cannot produce any kind of propulsion from our ship. Previous question: I know that there are two main ways to gain speed in ...
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Could we use the moon for a slingshot effect?

The slingshot effect or gravity assist maneuver produces a boost on the speed of the object which attempts to approach a planet head-on at a speed V while the planet is moving directly toward us at a ...
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Isn't the escape velocity for the solar system at the Earth 42.1 km/s? Then why does the graph show 36 km/s for the same value? Is the plot wrong? [duplicate]

The graph shows that 36 km/s is the escape velocity of the solar system at the Earth. But if we do some calculations, we will get 42.1 km/s as the right answer. I have been checking all other escape ...
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What are the disadvantages of gravity flyby assist?

Does the gravity assist get affected by any of the forces by other planets as they proceed towards the required orbit? Moreover what can be the other setbacks of gravity assist flyby?
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Is gravity assist provided by black hole as shown in Interstellar possible? [duplicate]

In our space missions, we use gravity assists by planets to change the speed relative to the sun. The speed relative to planets remains the same. We cannot use the sun for gravity assists. In ...
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Is there a way to get the angle of approach of a spacecraft with respect to a planet velocity vector?

I apologize if my question is badly formulated I know it's really specific but here what I would like to know : I managed to compute the turning angle of the velocity for a body along a hyperbola ...
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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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Can we significantly reduce entry velocity with this method by airbraking alone for interplanetary travel?

For example, can a space ship overshoot Mars in a reverse gravitational slingshot mixed with a little air breaking, steering to keep the spacecraft from orbit and then land on Mars with a near 0 ...
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How accurate can near earth asteroids be tracked?

To get more statistical significance for the suspected flyby-anomaly (or to refute it), it would be desirable to track as many hyperbolic earth flybys to within 1mm/s as we can get. Can we track ...
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Is the fastest way to Mars a solar flyby?

The recent question Launch windows to Mars got me thinking. Why is there only one or two launch windows to Mars ever other year? If you leave Earth heading for the sun, you should get a gravity ...
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Why is Osiris-REx using an Earth flyby gravity assist?

Osiris rode on an Atlas V 411. Why not use a larger rocket and skip the gravity assist flyby?
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Gravitational assists from bodies other than planets

Gravity assists are pretty important for interplanetary travel. NASA uses them mainly because they can save time, energy, propellant, and expenses. But so far, all of the gravity slingshots have used ...
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Why use the term “gravitational slingshot”?

I was reading about gravity assist. This maneuver is sometimes called a gravitational slingshot. But to me it seems more like a sling (like the one the Biblical David used against Goliath) The ...
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How slingshot is used to increase the speed of Juno [duplicate]

I have gone through the slingshot for the Juno with the earth. I have also seen the train and ball example as given by NASA. [http://solarsystem.nasa.gov/basics/grav/primer.php] But, I am still ...
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Is it possible to leave the Solar System by repeatedly using gravity assists from the Earth?

If a spacecraft was accelerated to just above Earth's escape velocity, it would begin orbiting the sun with an orbit very similar to Earth's. Could the spacecraft then repeatedly perform a gravity ...
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Could momentum transfer be practical (e.g., for orbital insertion at Pluto)?

Constraining exploration of outer bodies to flybys (such as New Horizons) seems unfortunate in terms of the amount of science that can be done per mission. Using a slower planetary approach has ...
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Multiple Gravity Assist from Moon to reach Mars

How effective can gravity assists from the Moon be at getting a vehicle from near earth to Mars? For this question, let's assume that a transit time of up to ten years is acceptable. Say we've put ...
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What are the gravitational assist effects on the inclination of a probe's trajectory, from passing by Jupiter at different latitudes?

A flyby probe at Jupiter gets its inclination, relative to the ecliptic, changed if it passes above or below Jupiter's equator. How sensitive is a trajectory to this effect? I imagine that there ...
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For what reasons are gravity assists used? What objects can be visited without such measures?

I'm trying to understand if it is only fuel efficiency that makes us use gravity assist, or we don't have enough rocket fuel in an average spacecraft to reach farther ends of solar system. Also, is ...
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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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Gravity assist and the terrestrial analogy: why does the velocity double?

The Wikipedia article on Gravity assist has this terrestrial analogy: Imagine standing on a train platform, and throwing a tennis ball at 30 km/h toward a train approaching at 50 km/h. The driver ...
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Repeated slingshot encounters with the same planet

I am curious to know how you calculate a slingshot direction change In both angle you are able to change per encounter (degrees) & the velocity ($m/s$) When $V_{inf}$ is higher than the planets ...
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What is the effect of gravity slingshots around Earth on Earth's rotation and orbit time, and is this effect worth considering?

Several space probes have used gravitational slingshots around Earth as part of their mission plan to get to other places in our solar system. Some examples I could find quickly are Galileo, Messenger ...
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Limitations of gravitational assist flybys

My understanding is that it's easier to send something out of the solar system than into the sun due to the need to overcome the speed at which the earth moves around the sun. My understanding of ...
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Why can't cubesats get gravity assists from space junk in Low Earth Orbit?

I have a simple question: Why isn't space junk orbiting Earth used for gravity boosts to launch small cubesats into higher orbits or to other planets? I know the current gravity boost and gravity ...
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How can Sun-Jupiter Lagrangian points be used by flyby probes?

Sun-Jupiter L1 is 1/3 of an AU from Jupiter. Could it be used to slow down or redirect a spacecraft approaching Jupiter? And the same for Sun-Jupiter L4 and L5 for a spacecraft on the way to e.g. ...
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Why did Voyager 2 receive a gravitational slowdown (as opposed to a slingshot) at Neptune?

I was actually answering this question today regarding velocities of spacecraft, and it occurred to me I've never really looked at this graph in much detail before: Heliocentric velocity of Voyager 2 ...
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Did the Pluto flyby give New Horizons any significant gravitational boost?

Last week New Horizons passed within 14,000 km of the center of Pluto. I assume this will have put New Horizons within the gravitational influence of Pluto. Pluto's average orbital speed is 4.7 km/s....
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How are gravity assists conceived?

So there are some very complex gravity assists out there. The Cassini mission, for instance, used a VVEJ (Venus Venus Earth Jupiter) gravity assist to make it to Saturn. Similar flybys have been done ...
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Why didn't New Horizon use Mars as a gravity assist like it did Jupiter?

Part of New Horizon's path took it near Mars. Why didn't they use Mars for a gravity speed boost like they did Jupiter? I'm guessing it had to do with the relatively small size of Mars being unable to ...