Questions tagged [orbit]
Questions regarding an object 'falling around' another object, due to a combination of gravity and momentum.
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Do the Galilean moons' orbits around the Sun have loops (i.e. have concave parts)? And if so, how can their orbits be graphed?
The shape of the Moon's orbit around the Sun has been discussed to death, and the answer is that the Moon's orbit has no concave "loops" whatsoever.
I am relatively sure that the determinant ...
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Celestial "orbits"
I heard that we're losing our moon, its slipping away from us in such tiny imperceptible steps that we don't notice any significant change even over kiloyears.
The same must apply to planets, inching ...
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Are there naked eye binary stars with periods less than 100,000 years?
An optical double is two stars which appear very close together because they chance to be lined up as seen from Earth but are actually tens, hundreds or thousands of light years apart in space.
A real ...
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Should you include aberration effects during low Earth orbit observations?
I am working on calibration of some observations of low Earth orbit satellites and I am wondering should I include aberration effects? My logic is that diurnal aberration would have neglegible ...
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Understanding laplace plane (satellite) orbits
Working on a little project (with vex+python in houdini) to calculate the planet and satellite positions using the keplerian formulae and a database of orbital elements and progressions. Primarily ...
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Is an earth-sized moon orbiting a super-earth feasible?
Is an earth-sized moon orbiting a super-earth feasible?
Or would tidal forces say 'no thanks'?
I'm making a system for the Kerbal Space Program Kopernicus mod and am trying to make it as realistic as ...
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Definition of a moon in an exam: "A satellite of a planet that *doesn't produce light itself but reflects it*" - is there relevance for the emphasis?
In a 5th-grade exam (for 10-11-year-old pupils in Finland), there was a question, "What is a moon?" The model answer was: "A satellite of a planet that doesn't produce light itself but ...
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What does the earth's (a planet's) orbit cause?
I know that the earth's rotation causes day and night.
It seems/feels so natural to think that the earth's orbit around the sun causes the seasons, but no it's the tilt of the earth's axis that causes ...
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Latest apoastron of Sirius
The only date that I can find for the latest apoastron of Sirius stars is 2019. Is there a more detailed date with at least the month and/or day. Obviously, it happened in 2019 but can't find any ...
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How do the orbits of star systems V871 Centauri (septuple), Gamma Cassiopeiae (octuple), and QZ Carinae (nonuple) work?
Several years ago, I asked the question on here, "How do the orbits of Nu Scorpii and AR Cassiopeiae work?" At the time, these two stellar systems were the most populated (I don't know the ...
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At what distance does the galactic tide significantly affect the orbit of a heliocentric object?
The title essentially explains the question. I was wondering if the galactic tide could play a role in raising perihelia of extreme trans-Neptunian objects (i.e. Sedna) versus the effect of a ...
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For binary stars, what is the average semi-major axis?
Note I'm exclusively considering binary stars, not 3+ star systems.
Binary stars come in all extremes. Wikipedia says that their orbital periods can be a few hours, a few days, or hundreds of ...
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Motion of solar system around Milky Way
As our solar system performs its +-230 million year lap around the Milky Way, is the orientation of the ecliptic plane preserved independent of the center of our galaxy, or does the plane perserve its ...
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A solar system of solar systems
The moon orbits Earth, earth orbits Sol. It's true that Sol orbits the galactic center, but that's not what this question is about.
Is it possible for a solar system like the Sol system, along with at ...
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Does the Sun have different unique orbits around barycenters?
After reading this question and seeing its image I thought about this question I'm going to publish.
Does the Sun have different unique orbits around the barycenter for its multiple planets?
If yes, ...
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Calculating Position of Sun in GPS Frame Relative to 0°00'00.0"N 0°00'00.0"E: Determining Vernal Equinox Offset
I am trying to calculate the position of the sun, in GPS coordinates terms, from a given date. As of right now, I know how to accurately calculate the equatorial Right Ascension and Declination, and ...
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Why isn't a month 28 days?
1 days is a rotation of earth. 1 years is an orbit of the sun. I've always beleived that one month is 1 period of the moon orbiting earth but the inconsistent distribution of days throughout the ...
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How do we know the Moon was much closer than it is now?
We know that right now, by measurement, the Moon is moving further away from the Earth. So I've heard the conclusion that the Moon was much closer to the earth in the past.
How do we know that part? ...
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Position of the Moon viewed from same spot couple of months apart
In the below image, the position of the moon as viewed from the same spot is displayed.
The drawing to the left is from today at local time of 2am.
The drawing to the right is from a couple of months ...
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Do all orbits emit gravitational waves?
In principle, all orbits in the universe should progressively decay due to the emission of gravitational waves. However, does this always happen? Are there any kind of orbits that do not decay as they ...
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Planets revolving counter clockwise around the Sun
Planets revolving around the Sun
Hypothetical case:
What could have been or no impact if the planets viz Earth, Jupiter, Saturn, Mercury, Venus, Mars, Pluto, Uranus, Neptune in different orbits ...
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Does Trappist-1 have a Periodic Configuration? [duplicate]
Trappist-1's planetary system is notable for having 7 planets in a resonance chain. I would think, since all the planets are in resonance, the system would have a repeating configuration that could be ...
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Satellite angular velocity at an angle
Suppose I am observing a satellite that is not at my zenith. I know the altitude(α) and azimuth(γ) of my telescope and I was able to get a relative angular velocity of the satellite.
Based on this ...
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How do I calculate the positions of an artificial satellite for a decade?
We are trying to solve what I think should be a simple question: suppose there is a satellite that is launched into a certain orbit, where will it be as a function of time? Let's say we know that it ...
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Why does the tropical year have a ~161 years cycle?
Using PyEphem, I calculated the time difference between consecutive summer solstices in the south hemisphere for the last 4000 years, and plotted them in a graph. It seems like random noise around the ...
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How to find the numerical positions of objects in the sky?
How do star locator applications such as SkyGuide, SkySafari and Stellarium get the current and future positions of
moons, planets, stars and artificial satellites in the sky?
Is there a public ...
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Can a star with a stellar mass of 1.176 with a similar composition to the Sun have a planet with these characteristics?
Imagine a solar system similar to ours that has a star with a similar composition to the Sun and a stellar mass of 1.176 and an Earthlike planet with about 1.18 times the mass of Earth in its ...
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What stellar conditions and orbital distance are needed to produce a year length of 515 Earth days and 9 Earth hours on an Earthlike planet?
A planet has a year length of 515 Earth days and 9 Earth hours. It is the same size and has the same climate as Earth. What stellar conditions would be needed to produce this and what orbital distance ...
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Which coordinate system should one use for simulating a spacecraft trajectory to the moon? [closed]
Which coordinate system is most suited for this type of problem? ecliptic? equatorial?
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Difficulty simulating trajectory of moon and sun for Apollo 11 mission
As an engineering student, I am doing a project about Kalman filtering and the mission Apollo 11. Now I tried to simulate the trajectory of the moon and sun for 3 days (the duration in which the ...
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largest balanced mass objects in Earth's L4 & L5 Lagrange points?
What is the largest single-object mass that would allow two objects of equal mass to have a stable orbit, one each, in Earth's L4 and L5 Lagrange points?
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Calculating Comet Position at a Given Julian Date with Available Orbital Elements
I have some orbital elements for comet P/2004 R1 (McNaught) from this dataset and I would like to calculate its position around the sun (x, y, z coordinates where the sun is at the origin) at a ...
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Eyeball planets experiencing "catastrophic" flips
This Youtube video by Anton Petrov shows research1 claiming that tidally-locked planets orbiting the same star in tight orbits may interfere with one another and one planet may cause the other to &...
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Is there an equation that can give position of a satellite around a parent body as a function of time?
I’ve been looking into this lately, and most sources I have used solve this problem numerically. I was thus wondering if there is a proper equation to solve for position without numerical, especially ...
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Are short-period comets more stable (in their orbits) than long-period ones?
Why the sharp distinction between short-period (P) comets of less-than-200-year orbits and those (C) with even slightly longer ones?
To explore the possibility that it has to do with stability, I will ...
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How to calculate solar ecliptic longitude
I would like to write a small script to calculate solar ecliptic longitude in relation to different locations and dates. For instance UTC + - 1...2 etc..
I know, solar ecliptic longitude is the ...
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Calculating the parameters of binary systems?
If I know the masses of the two bodies (they have equal mass), how do I calculate the two ellipse eccentricities, length of the apoapsis and speed at the apoapsis, that make stable system, as in this ...
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Would it be possible for a planet to orbit around a trinary star system in a figure 8 orbit?
I know that it is possible for a 3-body system to be "stable" in a figure-8 pattern. It's only stable if it is set up perfectly with no outside forces, but that's fine with me. If there were ...
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The possible Masses and Orbits of Hypothetical Moons of Proxima Centauri b
This question asks about the phases of a hypothetical moon of Proxima Centauri b.
What phases of a moon orbiting Proxima Centauri b could be seen?
And In my answer I suggest that Proxima Centauri b ...
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Does the Earth constantly lose mass?
The Moon is orbiting the Earth in a circular motion. To keep any object in a circular motion we need energy. Hence, does the Earth lose energy by pulling the Moon? In that case, does the Earth's ...
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Motion equation of a space engine in low-earth orbit
My goal is to simulate the movement/motion of a space capsule from low-Earth orbit with initial conditions emulating an initial thrust. Here is the code, Is it right? I know that the next step is to ...
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Can such planet orbit 61 Cygni A within a habitable zone?
I have developed a fictional planet I described here in Worldbuilding Stackexchange: https://worldbuilding.stackexchange.com/questions/231162/length-of-seasons-on-a-planet-with-eliptical-orbit.
Since ...
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Orbital decay of the sun's orbit around Sgr A*: is it likely?
What are the possibilities of the sun orbiting the black hole Sagittarius A* at a very close distance? Is there anything that could possibly alter the solar system's orbit, bringing it much closer to ...
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How light could the lightest objects able to exist in a stable orbit be?
Below a certain M1M2, gravity would get so weak that the masses wouldn't be able to orbit each other with stability, as other factors would overwhelm them, even in the quietest, stillest places in the ...
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Is there an orbit around the earth that experiences a total solar eclipse by the Moon at least every month?
Is there a way to design an earth orbit so that it passes through the Moon's umbra with greater frequency than total solar eclipses occur on earth's surface?
What is the maximum frequency of eclipses ...
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Problem with the Orbital Precession predicted by the Relativistic Acceleration equation used in the JPL D440-D441 Ephemerides - please advise
I have previously encountered a problem with the equation used by Yeomans and others for determining the gravitational acceleration of comets (see update in my answer to the previous question Can ...
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What is the galactocentric aberration?
At the Wikipedia about an aberration, there is the phrase:
a recommended galactocentric aberration constant of 5.8 µas/yr
What is the galactocentric aberration? How is it calculated correctly? An ...
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Galaxy plane and Earth's orbit. Connection to seasons?
From my understanding, the Earth (Solar System) crosses a center line of the galactic plane (ecliptic *edit wrong definition, sorry!), while orbiting around the Sun. The Sun also wobbles up and down ...
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Deriving orbital inclination from equatorial coordinates?
I wanted to ask if it's possible to establish a correlation between the observed equatorial coordinates of a Solar System planet, especially declination, and the planet's orbital inclination with ...
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Was Theia a planet or an asteroid?
According to an article Theia (from the Giant impact hypothesis) was an asteroid and according to The Wikipedia article about Theia Theia was an Earth trojan (which is an asteroid). Which is dubious, ...
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