Questions tagged [orbit]
Questions regarding an object 'falling around' another object, due to a combination of gravity and momentum.
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Convert Earth-centered coordinates to rotating libration point (RLP) coordinates?
I'd like to plot the path of an object near L2 (like the Webb space telescope) in a rotating libration point coordinate system. That makes it is easy to distinguish halo orbits from more general ...
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Can a planet with no atmosphere be orbited at extremely low altitudes?
Can a planet that has absolutely no atmosphere be orbited by a spacecraft at extremely low "altitudes" (if you'd even call it altitude at such a low orbit.
For instance, if this planet's ...
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What is the skypath of JWST?
JWST will be in a 6 month halo orbit around the Sun/Earth L2 point, which is located at the anti-solar point. Internet graphics give conflicting information on whether the skypath is clockwise or ...
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Is it still called an orbital resonance if the ratio is irrational?
Previously, I asked At what point are orbital resonances no longer "ordered" but "chaotic?", and received an answer from @CarlWitthoft:
Perhaps if the calculated fraction had an ...
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At what point are orbital resonances no longer "ordered" but "chaotic?"
Orbital resonances are typically in small valued integer ratios, like 2:1, 3:2, or 4:7. However, there are some resonances whose ratios have large reduced values, including the 73:69 Naiad:Thalassa ...
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What is the maximum latitude from which a satellite in a geostationary orbit around Saturn would be visible to an observer on the planet?
This question is part astronomy and part mathematics. I'm aware it involves “basic” trigonometry, but my brain is short-circuiting.
From my calculations, the distance from the center of Saturn where a ...
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2answers
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Incorrect Mars orbital time while calculating using Kepler formula in Java
Question:
I am trying to make a simple java program to do planetary orbital calculation like how many days it takes to complete the orbital along with each Earth day data but I end up getting a 4 ...
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How long would it take to realize there are "star-like objects" (i.e. planets) that change position in respect to the "fixed stars"?
If you were using unaided observations and were unfamiliar with astronomy (and maybe just pen and paper for recording anything), how long should it take to notice that Mercury, Venus, Mars, Jupiter ...
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Orbital terminology for satellites relative to one another
Basic question, but I'm trying to describe a planetary system and coming up short on vocabulary. Do either of the following exist?:
A word for the closest pass between two satellites orbiting the
...
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1answer
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What's the difference between the Roche lobe and Roche sphere?
I am just beginning to look into this topic, so apologies if there are any striking misconceptions in the following.
From Wikipedia, the Roche lobe is "the region around a star in a binary system ...
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1answer
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Would a system consisting of Earth and Venus orbiting around a common center be stable in the long-term?
Earth and Venus and very close to each other in mass and would both orbit around a point in space positioned almost perfectly in between the two.
Assume that this system is 1 AU from the Sun and the ...
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Could stars like S2 near the galaxy's center have planets in a stable orbit?
I read about one of the stars orbiting Sagittarius A* and according to Wikipedia, it reaches a maximum speed of 0.03c during its orbit. Would this (or any other factor) make it impossible for a planet ...
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How close to escape velocity are most Oort-cloud comets?
User @antlersoft wrote a nice answer to my question on the difference between barycentric and heliocentric models of the solar system when applied to comets (edge cases of the systems). In a comment, @...
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What is the difference between barycentric-centered and heliocentric-centered coordinates?
When talking about celestial bodies orbiting the sun with a decently circular orbit or small aphelion, the heliocentric orbital parameters are almost identical to the barycentric parameters. However, ...
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What was "wrong" about the motion of Neptune in 1984?
The cover story of the March 1984 issue of RUN, a popular computing magazine, was written by noted astronomer Charles T. Kowal. In the article, he describes how he uses his home computer, a Commodore ...
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Does the .43 arc-second per year deviation of Mercury's orbit from Newtonian predictions mean that its position is 'off' by 75 miles per year?
If I divide the elliptical circumference of Mercury's orbit by .43 arcseconds, I get an answer of almost exactly 75 miles....
BUT, it is the precession of the periapses that is off, not 'just' its ...
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Why are triple conjunctions in a resonance forbidden?
I was reading the Wikipedia article about orbital resonance and noticed that Laplace resonances forbid triple conjunctions. This seems to be supported by the Io-Europa-Ganymede system and the Nyx-Styx-...
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Repetition of orbital structure on many scales - what is it called?
I'm certainly not the first to notice this, but there is a commonality between the structures of objects in space at different levels of magnification. For instance...
The moon orbits earth...
The ...
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1answer
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Why is there a deviation between the ratio of $a^3$ and $T^2$ for the outer planets?
The Wikipedia article about Kepler's third law includes a nice table about the ratio between $a^3$ and $T^2$. However, for Mars, Jupiter, Saturn, Uranus, and Neptune, the ratio $\frac{a^3}{T^2}$ in $...
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How was the speed of the Sun (around the Milky Way Galaxy) calculated?
The Sun travels around the Milky Way Galaxy with a speed of 220 km/s. The question is: where did this value come from? Is there any article about the calculation?
Reformulated question: What are the ...
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1answer
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Are intersecting orbits ever stable?
Ok, I'm asking this question because the obvious counterexample is trojans. Trojans typically intersect the orbit of its relative body. Typically, these are stable in the long-term, especially when ...
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Average DeltaV applied to a comet during outgassing?
Comets' orbits often change during perihelion passage due to the outgassing of volatiles. So I am wondering, how much change in velocity is applied each perihelion pass? What does this depend on?
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Why do planets' orbital velocities drop off by less than a third when twice as distant from the sun, rather than three-quarters? If gravity is $1/4$?
Looking at the speeds of the planets in our solar system when traveling around the sun and their distances from it (or, using Kepler's third law,), it seems that when a planets distance is doubled, it'...
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Asteroids in polar orbits?
I'm conducting research on solar system dynamics, and found a list of asteroids in retrograde orbits, but none about the ones orbiting perpendicular to the ecliptic plane. Are there any detailed lists ...
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Will Mercury ever become locked to the Sun?
The Mercury year is between 1 and 2 days. Has it ever been greater, and will it eventually become "tidally locked" with the Sun?
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When will Alpha Centauri A and B overtake Proxima Centauri as the closest stars to us?
There are 3 stars in the Alpha Centauri system: 2 large stars orbting around each other (A & B) and a distant Proxima Centauri (C) orbiting around both.
Right now it just happens that Proxima ...
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1answer
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What are the minimum variables that determines the orbital velocity of a planet?
I will try and be brief with this. I want to model a star system in a programming language. It has been a very long time since I did physics.
This says that planets have a speed given to them by the ...
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How often does the configuration of the Trappist-1 system repeat
My question is simply how long it takes for the 7 known planets in Trappist-1 to be in the same configuration in relation to their host star, and to each-other. Those seven planets are in a 2:3:4:6:9:...
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1answer
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How long is a mean Jovian tropical year in Jovian solar days?
Many sources say that Jupiter's year lasts 10,475.8 Jovian days. When I calculated to see if that's correct With the data NASA had published, I found out it's the measurement of a Jovian sidereal year....
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1answer
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How to predict future position of body in solar system (without Kepler's equations, N-body problem)?
I have a solar system where each body interacts with each other by force $F = \frac{Gm_1m_2}{R^2}$
Is it possible to predict future position of some random body after t seconds since bodies velocity ...
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What precisely leads to planets like COCONUTS-2b to orbit so far away from their host stars, 6000 AU in its case?
Taking our Solar System as an example, most gas giants formed relatively close by (a few AU) and drifted away to reasons I don't know, from an explanation I recall reading. Simply orbiting a few AU ...
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Why doesn't Triton orbit over Neptune's equator?
In this answer, I wrote (on another account) why most moons orbit over their planet's equator.
Any rotating planet has an equatorial bulge that shifts its moons' orbits around its equator over long ...
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1answer
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Confused on how you are supposed to calculate eccentricity without apsides
I'm kinda confused on how to calculate either the apsides or the eccentricity without knowing one or the other. Let's say you have an object in orbit around another. If you know the current distance, ...
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Retrograde and Crescent Phases Visibility on Mars
So I saw this question online
If you lived on Mars, which planets would describe retrograde loops? Which would never be visible as crescent phases?
And on a few QA website I searched, they gived ...
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1answer
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What if a component of a binary star lies in the center of it's orbit and not in the focus?
I'm trying to solve this task:
Observing a visual binary star with a highly elongated elliptical orbit for a long time, the astronomer noticed that the bright component lies in the center of the ...
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2answers
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Is it possible for a planet to heat up its moon to habitable temperatures solely through infrared radiation?
Stars are powered by nuclear fusion and the energy released radiates through their surface as heat. But all objects radiate away some form of electromagnetic radiation depending on their temperature.
...
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Is Jupiter warming the Earth? (Earth, Sun Jupiter system)
If Sun-Jupiter baricentre is outside the Sun, does that mean the Sun is orbiting around that point too right?
Then the Sun shouldn't be nearer to the Earth at some point during the Sun-Jupiter orbit (...
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Can a satellite stay in one place but not above equator? [closed]
I know that there are geostationary satellites that are always seen in one place in the sky and that they all are located in the equatorial area. I wonder if it's possible for a satellite to "...
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1answer
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Are there automatic methods to locate (stellar and supermassive) black holes?
Black holes have been discovered using several techniques, as outlined by How are black holes found?. What I was wondering is: are there automatic methods for locating them (e.g., artificial ...
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1answer
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Best way to procedurally generate an orbit given mass and eccentricity
As stated here, I've badly expressed my problem and have made what we call a XY problem (the question was well answered nonetheless) so I restate the question. Sorry for the inconvenience
I have a 2D ...
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2answers
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Given mass, position and eccentricity, is there a way to get initial velocity in a 2-body problem?
I know that the we can get the eccentricity vector like that: $\mathbf{e} = \frac{\mathbf{v} \times \mathbf{h}}{\mu} - \frac{\mathbf{r}}{\|\mathbf{r}\|}$ (source: https://astronomy.stackexchange.com/...
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2answers
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Are the major-axis of Mars and Earth orbits on the same plane?
Which means that I can draw an imaginary plane that contains the major-axis of both Earth and Mars.
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2answers
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Do all the orbits of planets in the Solar system fit in a (imaginary) cone?
So that all the elliptic orbits can be seen as slices from the cone while the sun is a shared focus.
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What's the formula for change in argument of periapsis over time due to J2 perturbations for a geocentric satellite?
I'm trying to propagate the orbit of the ISS, but it became very clear to me very quickly that the J2 perturbations were nothing to scoff at.
A quick google search gave me the equation for the change ...
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Why doesn't the Moon fall out of orbit?
If you need to boost ISS to stay in orbit why moon doesn't fall down to earth and KABOOM?
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Is there a formula for a planet's orbit in a 3D space?
I'm trying to model the orbits of Earth and Mars and their positions at a given point in time. But I can only find 2D equations of elliptic orbits, which only contain the x and y variables. I have to ...
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2answers
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How to calculate eclipses on a planet in a binary star system
I posted this question on the physics page but decided it might be best if I post it here instead as it may be a more astronomy related question. I also haven't received any answers over there so far ...
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1answer
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The Sun's motion around the galaxy [duplicate]
As the Sun orbits the Milky Way, I understand that it also moves up and down through the plane of the Galaxy. How long does this movement take and can we tell where we are in the current cycle.
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Is the barycenter of the solar system usually outside of the sun?
I came across this picture on wikipedia:
Note: From a quick search I gathered that although there are slight differences between the limb of the sun and the accepted radius of the sun, these ...
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1answer
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Are we able to accurately predict planetary orbits over a longer period of time?
I was wondering whether planetary orbits can be predicted with our classical theories, or whether quantum randomness comes into play making the unpredictable in the long run?
