Questions tagged [gravity-assist]

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

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4
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2answers
183 views

Was the gravity assist at Jupiter the most dangerous part of the New Horizons mission?

In terms of success of the mission, was the Jupiter fly-by the time when problems with the flight path was most likely to happen? Was the odds of failure at that point ever studied? If so, what were ...
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Is it more efficient to burn all needed fuel in an Oberth manoeuvre at once or burn a fraction of the fuel for each orbit?

I was looking into Parker Solar Probes trajectory and was wondering what would be the most optimal way to utilize a retrograde thrust at perihelion to reduce the number of needed gravity assists. I ...
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Speed at aphelion is decreasing for Parker Solar Probe with each new orbit despite being closer to the Sun

Sorry for the really bad picture I am looking at some data from the Parker Solar Probe mission and I was looking at the speeds of PSP at perihelion and aphelion at each new, different, orbit (the ...
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1answer
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Effect of incoming velocity on change in velocity in a gravity assist

In a gravity assist does the incoming velocity of a space craft effect how much speed it gains. For example say a rocket was approaching Jupiter for a gravity assist with speed v and another rocket ...
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1answer
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Why is the highest speed that Voyager 2 achieved from the Jupiter gravity assist not at perijove?

I plotted some data of the speed of Voyager 2 for various times (around the Jupiter flyby) and noticed that the highest speed that Voyager achieved was not at perijove and was wondering why this might ...
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Where can I find the specific details of a gravity assist space mission?

0 I am writing a research essay where I need to know the specific details of a gravity assist mission such as Voyager 2's flyby of Jupiter for example (but any mission would work as long as it is a ...
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What is the relationship between the periapsis altitude and the change in velocity in a gravity assist?

In a gravity assist maneuver if I were to decrease the distance from the rocket to the periapsis of the planet it is orbiting (I believe this is called the periapsis altitude but I may be wrong) it ...
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Have space probe gone to unplanned destinations?

Reading this question about multiple gravity assists (Why is Voyager 1 faster than all other space probes?), it caused me to wonder if any probes have been redirected to additional (or alternate) ...
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What do the shaded vertical lines in the animation of Gravity assists of space probes, mean?

Example Animations from Wikipedia — https://en.wikipedia.org/wiki/Gravity_assist#/media/File:Animation_of_Voyager_1_trajectory.gif https://en.wikipedia.org/wiki/File:...
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Is a graviational slingshot around Mercury a feasible solution for space probes?

Our spacecraft have rarely visited Mercury, for reasons obvious to those who know orbital mechanics. The Mariner 10 visit to Mercury was revolutionary by using Venus for the novel slingshot maneuver, ...
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Will Dragonfly flyby Jupiter en route to Saturn?

The table on the "Exploration of Jupiter" Wikipedia page suggests Dragonfly will be the first mission to the outer planets that will not use a gravity assist from Jupiter. Is there a source confirming ...
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Why does Voyager 1 lose speed after the sudden gain in speed from gravity assist?

The Voyager 1 loses speed gradually after gaining speed from gravity assist. Is the external thrust is applied in the opposite direction to move closer to the planet, or does the spacecraft lose its ...
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1answer
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Rockoon on steroids

In typical rockoon a balloon is the lifting body to the upper atmosphere where a rocket is released and ignited. But I would like to ask about a variation to launch small payloads to space. Instead ...
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1answer
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How exactly did Jupiter change Ulysses orbital plane from nearly ecliptic to polar?

Ulysses spacecraft trajectory is truly amazing. Utilizing gravity assist from Jupiter it was sent into polar orbit around the Sun. I can understand gravity assist concept, I can also (intuitively) ...
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Could we reverse gravitational slingshot a fast object to slow it down and capture it in an orbit?

I have heard of plans to capture an asteroid in an orbit around the earth, to have it close by so that we could study it more easily. Such objects can have very high velocities, (I assume) possibly ...
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Free Return Transfer Problem

I'm trying to understand how a free-transfer return works. It makes sense to me conceptually, but putting numbers to it it is unclear. I'm not sure how to obtain information about the transfer ...
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1answer
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What is the fastest velocity to which something can be accellerated using a gravity assist [duplicate]

My understanding of gravity-assists (slingshot) is that they use some of a more-massive object's orbital energy to gain massive acceleration. What's the upper limit on how much velocity an object ...
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STK Astrogator Earth Flyby

TLDR: How do you set up an EEV maneuver, specifically, how do you go from an earth orbit to a heliocentric orbit with a periapsis within Venus’s orbit in astrogator? I know the theory but astrogator ...
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History of the planetary flyby for gravitational assist; first conception, mathematical demonstration, plan, and execution?

Planetary flybys for gravitational assists are a stable of deep space missions. When did the following things happen? First documented realization that gravitational assists in spaceflight were ...
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Do you need to burn fuel between gravity assists?

If you are planning a mission to an outer planet with multiple gravity assists included, do you need to do some burns for corrections, between the slingshots, or the ideal trajectory is already ...
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Were there any identified launch windows and gravity-assist trajectories that could put a probe on a “Grand Tour” trajectory around 1981?

For context, I am developing an alternate history that features a far more ambitious Voyager program than the one undertaken in real life. However, despite the increase in NASA funding provided in the ...
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How to plot conic from Lambert solver

I am trying to solve for an optimal multi-gravity assist trajectory from Earth to Saturn using Matlab. I have already solved for the departure and arrival velocities from and to each planet using a ...
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Gravity assist from Mercury

The Oberth effect states most energy can be gained when you have highest velocity in orbit. The interplanetary missions, generally involve ion propulsion along with gravity assist from planets such as ...
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Can a “gravity assist” at a black hole accelerate light faster than the speed of light? [closed]

With the help of a gravity assist from a black hole, can light travel faster than its natural light speed?? Satellites use gravity assistance. In a similar way can light traveling near black hole ...
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Gravitational keyhole for spacecraft flyby?

Is there a term for the area near a planet a spacecraft must pass through for a gravitational-assist flyby, or does 'gravitational keyhole' apply to gravitational assists as well as for asteroids?
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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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Will a spacecraft accelerate in a gravitational field via the use of a powered rotating mass?

I believe that a powered rotating mass on board a spacecraft should result in the spacecraft being propelled in a continuous increasing velocity towards the source of the gravitational field. To help ...
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What Jovian system science targets would be suitable for Jupiter gravity assist flyby missions with other primary purposes?

Flying by Jupiter for gravity assist, and with the Oberth effect bonus, has been used for multiple missions to other outer planets and to comets. And has potential for use even for missions aiming at ...
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What is the smallest body in which a sling shot maneuver can be performed?

This question asks about the smallest sling shot maneuver performed. What was the smallest intentional, acknowledged slingshot maneuver? I'm asking how small of an object be to perform a sling shot ...
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What was the smallest intentional, acknowledged slingshot maneuver?

I'll keep it short but please read through! Gravitation's $1/r$ potential means everything in the solar system is pulling on everything all the time. Gravitational slingshot maneuvers are normally ...
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How fast can an orbit exist in the solar system?

How fast is too fast to stay in orbit around any particular large body in the solar system?
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Why didn't Voyager 1 and Voyager 2 crash on into Jupiter or Uranus when they approached near to these massive planets?

I was reading about gravity assist and I read that both the Voyagers used gravitational force of these planets to speed up. But I wanted to know why weren't they completely attracted by their ...
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How much does a swing-by change the orbit of the planet?

A friend of mine told me that one Voyager swing-by moved the orbit of Jupiter a foot closer to the sun. I understand that Jupiter was slowed by the gravity assist, but I figured it would be minuscule ...
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Determining the spacecraft position vector with respect to ICRF frame for Venus flyby

For an interplanetary mission design to Saturn, I have considered doing multiple gravity assists starting with Venus. I am using the JPL Horizons ephemeris and ESA Lambert Solver. I have the ...
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1answer
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Perpetual motion [closed]

When I was young, I had a set of bar magnets which had poles on the side faces (across the thickness) and not at the two ends. I placed one on the table facing one pole upwards (say north pole). ...
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1answer
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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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The dreaded apocalyptic asteroid approaches Earth but lands safely on the Moon at zero relative velocity

An asteroid approaches and the Moon 'catches' it in the same way that a sports player catches a ball - that is to say by matching the velocity of the hand to that of the ball. Could a lucky slingshot ...
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Venus gravity assist (and aerobraking) - How much delta-V can it add?

The Voyagers made a grand tour using the gravity assist of each planet. But Jupiter, with a 12 year orbital period, doesn't always line up to be useful for spacecrafts destined to further planets. ...
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Multiple gravity assists [closed]

Is it possible,just by looking at the heliocentric position and velocity vectors of the spacecraft and the planet,to decide whether the resulting flyby would be trailing or a leading flyby? If yes, ...
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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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1answer
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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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1answer
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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 ...