Questions tagged [flyby]
Questions regarding flyby in which the spacecraft flies near celestial object in a hyperbolic path for scientific explorations. Such flybies may also be made to increase velocity or reduce the velocity via a gravitational assist.
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Can Tisserand's parameter be modified to correct for perturbing eccentricity?
Tisserand's parameter is an "almost" conserved quantity in the CR3BP, even after flybys (useful for identifying asteroids).
$$T_P = \dfrac{a_p}{a}+2\sqrt{\dfrac{a}{a_p}(1-e^2)}\cos(i)$$
It ...
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Longest time between Earth flyby for active space mission
I'm wondering what the longest time was that passed between the first earth flyby and the second.
Lucy did a flyby on earth in October 2022 and will do its last currently planned flyby in 2030. So ...
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Was it possible to do a course correction on the planned manned Venus flyby?
Once the burn was complete, any remaining propellant would be vented to space, and then the larger fuel tank could be used as living space, while the smaller oxygen tank would be used for waste ...
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What happened to Mariner 2 after it flew by Venus?
I found myself wondering about what ever had happened to the Mariner 2 spacecraft (the first successful flyby of any planet) after it flew by planet Venus.
According to apesinspace.co it "...
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Optimal depth for underground flyby?
Planetary flybys are used to modify the orbital parameters of spacecraft.
For maximum gain, a large deflection angle is often desired. But the deflection angle is limited by the closest approach, ...
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How does one design a trajectory involving a lunar and Earth flyby and Lagrange points? What tools are used to calculate the initial guesses?
I'm trying to design a trajectory that takes a spacecraft from Sun-Earth L2 to a lunar flyby, to an Earth flyby and then to Mars (two flybys might be too complex, I might just do one). I've optimized ...
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Would it be practical to fly a probe to Mars using gravitational assistance from Venus?
I decided to fly to Mars in KSP using a slingshot of Venus to see if I could save fuel. Since Venus is closer to Earth, you need less fuel to get there. When I tested it I used less fuel, but the ...
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Is there a parameter that describes the angle between the spacecraft's position and the sun angle or direction of the Earth's motion?
I am trying to design an Earth flyby for gravity assist in GMAT, and I know from theory that the spacecraft should pass in front of a planet with regard to its heliocentric direction of motion in ...
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How many solar system bodies have had their magnetic fields directly measured?
Discussion below this post lead me to wonder:
Question: How many solar system bodies have had their magnetic fields directly measured?
Inferences from radio or spectroscopic observations don't count ...
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Which deep-space spacecraft flew closest by Earth during a gravitational assist?
The extremely cool NASA JPL video Triumph at Saturn (Part I) is really worth a watch and/or listen. (Don't forget Part II as well!)
At about 26:30 it discusses ...
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Flyby puzzler; starting from Earth, how many times can you use Jupiter flybys in one century?
Is there any limit to how many times you can increase velocity by repeated sling shot manoeuvres? and its answers have got me thinking, and that's always dangerous.
Suppose you have a durable RTG-...
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Did New Horizons look for "sailboats" in the Pluto-Charon system's sailboat region? Did it pass through it or avoid it?
In this answer to If we could send an orbiter to the Pluto-Charon system, could we put it in a stable orbit? I wrote:
Totally by accident I've just happened to run across the 2014 open access paper A ...
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Direction of heliocentric entry velocity for fly-by coming from interplanetary Hohmann transfer?
I'm following Curtis's equation on interplanetary transfers. I'm confused by the direction of the entry Heliocentric velocity for a fly-by.
If the assumptions is that orbits are:
Coplanar, cofocal ...
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How are B-Plane parameters actually determined for a planetary flyby?
Reading from this document, I am trying to simulate the New Horizons probe trajectory in GMAT and I am puzzled with how the authors of the original paper (by legendary mission designer Robert W. ...
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How to calculate the maximum heliocentric speed during a flyby?
The following graphs are related to the Voyager 2 / Jupiter flyby occurred on July 1979 (I did the calculation with the SPICE library and NAIF’s data files).
We see that the maximum speed relative to ...
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How does a spacecraft navigate along and jump between constant v-inf lines depicted in Tisserand graphs?
Below is an example Tisserand graph showing interplanetary trajectories (in bold black).
The first one represents a trajectory from Earth till the Mercury system. In the second one, the spacecraft ...
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How to design a lunar flyby trajectory in GMAT?
I am trying to design a flyby mission to the moon using electric propulsion on GMAT. I've gone through the tutorials, however, the most useful one "Lunar Flyby to the moon using multiple shooting&...
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Will crewed vehicles ever follow multi-flyby trajectories?
A while ago, I asked a similar question here, but I think it was confusing, so nobody answered.
Two questions:
This one is a bit subjective: Do you think that lengthy (+5y) multi-flyby trajectories ...
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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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Orbit transfer trajectory options to the moon
I am working on a project for a lunar flyby using a CubeSat. I was wondering what kind of trajectory transfer options are present and which one would be best for a CubeSat? I'm aiming for a transfer ...
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How is flyby distance estimated?
The New Horizons spacecraft performed flybys of 134340 Pluto and 486958 Arrokoth in 2015 and 2019, respectively. The orbits of these satellites was not known to the kilometer (or maybe even thousand-...
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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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How much less delta-v would it take to reach the Sun using Venus and Earth flyby's compared to direct?
@TomSpilker showed that the minimum delta-v to go from Earth orbit into the Sun is about 20.89 km/s. That's going from 200 km LEO to "perihelion at the sun's photosphere (guaranteed complete entry!)" ...
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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 are these mysterious white star-like dots near MU69 Ultima Thule? Real objects near the asteroid, noise, cosmic rays, or something else?
NOTE: I think either possibility suggested below is possible, I'm not looking for arguments why one of them would be your favorite like this answer. Instead, I'm looking for a fairly conclusive answer;...
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Does JPL's Horizons have better MU69 state vectors for the New Horizons flyby somewhere?
Today I downloaded the state vectors for New Horizons and MU69 Arrokoth and subtracted their positions. The two new get closer than about 596,000 kilometers.
The New Horizons output header says:
<...
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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 to calculate New Horizons' MVIC camera max resolution at Pluto and Ultima Thule?
I am in trouble calculating the ground resolution of MVIC instrument onboard New Horizons; I found several documents about MVIC specs, like this one:
http://www.boulder.swri.edu/pkb/ssr/ssr-payload-...
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What time will news from New Horizons' Arrokoth (2014 MU69) encounter become available to the public?
This is New Years Day and the big day for New Horizons' encounter with Arrokoth!
But it doesn't mean there was nice pictures of MU69 on the big LED displays in Time Square at ...
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What angular resolution is expected during New Horizon's flyby of Ultima Thule?
Ultima Thule is thought to be about 20 miles (30 km) across. However, I can't seem to find any information about approach distance or typical image resolution of New Horizons in regards to this second ...
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How would a Jupiter flyby have helped to get to the Sun? Why was it later ruled out?
The quote below surprised me. What were the orbital mechanical details of using a Jupiter flyby to get a probe from Earth so close to the Sun? Was a "U-turn" possible; single flyby of Jupiter into a ...
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What is the closest fly-by of a planet/moon ever completed?
I was thinking that on a fly-by of the moon, due to a lack of atmosphere, you could get really close! Of course, in practice this isnt a very good idea- going 1000m/s 50 meters above ground wouldn't ...
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How close to the moon would a flyby trip likely attempt?
For a flyby of the moon, like the SpaceX #dearMoon flight announced September 17, 2018, how close would they likely attempt to pass?
Is there an average or optimal trajectory for a lunar flyby used ...
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Delta-v obtained from Titan by the Cassini spacecraft; just how much of a "gas tank" was it?
In the video Cassini at Titan: A World Unveiled after about 01:56 Linda Spilker, Cassini Project Scientist, Jet Propulsion Laboratory says:
Not only was Titan ...
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Any news of TESS' lunar flyby; how well did go?
According to this TESS tweet:
TESS is on track for a lunar flyby on 17 May at 06:34:35 UTC (2:34 AM EST). At this point, TESS will be 8,253 km from the lunar surface. In the coming days, follow @...
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(How well) Did Juno provide any insight into the Flyby Anomaly?
I ran across an old BBC article titled Juno: The spacecraft putting sling theory to the test — Why a probe passing our planet on its way to Jupiter might end a decades-old mystery, and reveal ...
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Is the Flyby Anomaly still a thing?
The Flyby Anomaly is a name given to an unexplained, unexpected difference between the best theoretical calculation of a change in several different spacecraft's velocities due to flyby (Gravity ...
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Could a probe fly through the Sun's transition zone between chromosphere and corona?
I wonder if a cryogenically cooled probe could fly very fast tangentially pass the Sun and through its transition zone where the temperature drops to below 6 000 K, from millions in the corona. What ...
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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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How many asteroids could a retrograde probe in the Asteroid Belt flyby?
Cassini makes frequent flyby's of moons at Saturn. If one similarly put a probe in retrograde heliocentric orbit in the Asteroid Belt, how frequent could one expect to make a near flyby, given the ...
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How is JunoCam different from a normal CCD camera?
JunoCam has tweeted us! More background from the BBC.
It is supposed to have several features that help allow it to work in the high radiation and magnetic fields it will experience during each ...
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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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Any interest in crewed mission to Mars without landing?
Would there be any interest in a manned mission to Mars without landing?
This could consists of none (just a flyby) to many revolution(s) around the planet.
Would it cut a consequent part of the cost ...
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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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Are there any free return trajectories for a manned Mars flyby mission between 2018 and 2024?
I am looking for a mission profile including the delta-v for burns for an interplanetary mission to Mars. I have been unable to find any free return trajectories between 2018 and 2024, are there any?
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How can one spacecraft (MANTIS) fly by multiple (7) asteroids?
MANTIS was in 2015 a proposed Discovery class mission which were to fly by seven different asteroids including at least one NEA. I think the spacecraft which holds the record in number of flyby's is ...
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A constant parameter in a three body system?
In a two body system, there are a lot of orbital parameters not changing over time, like eccentricity or the orbital plane.
A constant parameter can be a combination of two or more, like even though ...
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What are the "crossing beams of light" in the Cassini images taken during Enceladus plume flyby?
Whilst checking the latest images of the E-21 flyby returned by the Cassini probe, I've noticed that some of them show interesting optical phenomena that I'm not sure I can explain;
For example, on ...
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What is the closest flyby to date?
Cassini is to fly within 50 km of Enceladus.
What is the closest flyby a spacecraft has ever made? What object was targeted and when was it? Is 50 km a new record?
(For the purposes of this question,...
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Cassini flyby through Enceladus plume - How risky is that for the spacecraft and its instruments?
This Wednesday, October 28 2015 at 11:22 a.m. EDT (15:22 UTC), Cassini spacecraft will flyby through the Enceladus plume at only 30 miles (49 km) altitude to analyze plume chemistry with its ion and ...
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