Questions tagged [orbit]
Questions regarding an object 'falling around' another object, due to a combination of gravity and momentum.
448 questions
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How long a photon stay suspended in orbit around a black hole?
Can a black hole free from an accretion disk collect photons in the photon sphere in a prolonged stable orbit?
Could enough photons be in orbit to shade the actual black hole with light?
Would a ...
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1answer
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How was Cruithne's orbital time calculated?
How was it determined that Cruithne takes 770 years to complete its cycle with Earth? Janus and Epimetheus were disovered long enough ago, and have short enough cycle times, that we've had time to ...
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nonagesimal in Kepler's parallax computation
I'm starting to learn Kepler's Astronomia Nova using William Donahue's translation . In the translator's introduction, it is demonstrated how Kepler did his parallax computation. I failed to ...
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1answer
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How close to circular is the Earth's equator
Earth's orbit is about 99% circular. How circular is Earth around the equator? I know it bulges around the equator and is a spheroid. I also know it is not smooth and has oceans and mountains and all ...
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What variables are needed to calculate simple horseshoe orbit times?
EDIT This was NOT a duplicate of Horseshoe orbit cycle times.
But that other question has been deleted, regardless. My original question asked for the answer to the equation(s), and provides many of ...
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2answers
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Is it possible to see a spacecraft orbiting the moon with a pair of binoculars?
On this clear early morning over London, I was studying the moon with a pair of binoculars and noticed a tiny dot of light that appeared to trace a slow orbit around the moon. I reckon it moved ...
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does the orientation of orbital plane of our solar system rotate with the galaxy
As I understand it, our solar system travels through the milky way with the orbital plane tilted about 60 degrees so that we are sort of traveling in the direction of earth's north. My question is if ...
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Could a moon orbit an Earth size planet in such a way as to create a solar eclipse lasting for several weeks from start to finish?
Is it theoretically possible for a moon to orbit a planet (let us say Earth size, mass and solar distance) in such a way as to create a planet-wide solar eclipse lasting several weeks?
These are my ...
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Do we know if there are asteroids leading or following Earth in Earth's orbit around the Sun?
A search of the Internet is so clouded with discussions about the asteroid belt or asteroids orbiting the planet Earth that I couldn't see an answer to my question.
Do we know if there are asteroids ...
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Do Mercury and Venus exhibit retrograde motion?
This is more a terminology question, since Mercury and Venus certainly "move backwards" in the sky. The question is whether we call this retrograde motion. I'm referring to apparent retrograde motion ...
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Earth Orbit Simulator [closed]
I'm trying to simulate Earth's orbit using 2nd Newton's Law and cartesian coordinates. The program seems ok, but when plotting graph, it's a parabola.
I know the shape of orbit changes according ...
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When is Earth closest to the Sun?
When is Earth closest to the Sun?
Well, you say, perihelion of course. But perihelion is when the Earth-Moon barycentre is closest to the Sun. Not Earth itself.
The barycentre is on average 4,671 ...
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Possibility of certain conditions on a planet [closed]
I want to know if there can be any planet that can fulfill the following conditions and if any planet has been observed with such characteristics:
The planet must not be tidally locked.
The day-night ...
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1answer
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Tidally locked, and yet spinning?
Reading about Uranus almost 90° tilt, I was wondering if some rocky planet with mass concentration at one pole could possibly spin around its own axis, while still being locked to its star? Which ...
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3answers
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How fast would an object at cruising altitude(around 10,600 m) need to travel to stay on the opposite side of the Earth to the Moon?
I am trying to figure out how fast an object will have to travel (at a height around 10,600 m) to never be in the presence of the moon. Meaning the object will always be on the opposite side of the ...
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Why is Uranus able to support a regular satellite system?
Uranus has an obliquity of 98° which means that the mutual inclination between a satellite orbiting in its equatorial plane and the orbit of Uranus around the Sun would exceed the critical angle for ...
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Computing the local orbital frame vector directions in a geocentric reference frame
In the context of the study of a cubesat (little satellite), I am asked to define the local orbital frame and compute the local orbital frame vector directions as a function of time :
Here the ...
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How uniformly is cometary debris distributed along the entire orbit of the comet?
Meteor showers occur when Earth passes through debris shed by a comet (if I get that right). Does this mean that the entire orbit of the comet is strewn with debris? I suppose that the debris follows ...
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How much does being at the perihelion heat Earth up?
The author in this article: https://news.nationalgeographic.com/news/2010/07/100707-aphelion-heat-wave-earth-sun-science-weather-nation/ has explained that positional differences on the orbit is a ...
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2answers
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Is Earth's true anomaly roughly 1 degree currently?
I wrote software which uses GMT real time to calculate Earth's mean, eccentric, and true anomaly. I encountered a bug where after reaching 360 degrees, instead of flipping back to zero, it subtracts ...
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How to convert a function of keplerian elements to a function of equinoctial elements?
I need to convert the Keplerian orbital elements to the equinoctial elements and then use the converted elements"equinoctial" in the function "d" below. To do this, first, I converted the Keplerian ...
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Is a precession rate of -0.67 radians/orbit plausible?
I came across the paper Rodin & Starovoit (2018) about the possible existence of a planet around the pulsar PSR B0525+21, which suggests the existence of a 0.387 Earth mass planet with the ...
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Expansion of Jupiter's perturbing effects on Kepler's third law treatment of orbits?
Does anyone know any good reference for how this was done?
I remember reading once about how Jupiter's gravitation can be treated as a perturbation, but I cannot find it again now. I think they ...
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Why do satellites arcs end abruptly when observed from Earth
I recently got an app that let me track the ISS. I noticed that during the time it's visible, it disappears before reaching the horizon, and sometimes reappears soon after for a bit.
Can somebody ...
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1answer
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Extract anomalies from two-line element set (TLE) on ISS (International Space Station)
I am faced to a problem of interpretation illustrated on figure below :
From wikipedia : Two-line element definition, I can extract the
following meaning anomaly : 308.7017 ° (in degrees)
But in ...
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1answer
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Warm jupiter vs hot jupiter, fluffyness
If Jupiter was orbiting at 1AU, replacing Earth, but everything else in the solar system remained as it is currently, how much would the increased heat from the sun increase Jupiter's radius?
In ...
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Is there a name for this type of orbit of a natural satellite?
Is there a name for the orbit of a natural satellite of a planet who's period is the same as the rotational period of the planet, but the orbital motion has the opposite sense than the planet's ...
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1answer
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Why is Neptune true anomaly decreasing?
So I've been having fun with trying to determine where the perihelia of different planets are (using JPL Horizons).
And by the time I got to Saturn, something weird started happening. I've noticed ...
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2answers
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How can we learn the inclination of the orbiting plane of the exoplanets using radial speed method?
I heard about the radial speed method to discover exoplanets a few years ago, however, these questions kept confusing me. If we know a planet star of mess $m$ is orbiting a star by interpreting the ...
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1answer
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Precise declination of Moon
The moon follows 5.14 deg inclined path. the ecliptic and the Moon's path coincide are called 'nodes', and they travel around the ecliptic in a period of 18.66 years.
Once every 18.66 years, the ...
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2answers
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How could the Moon have arisen from a collision - what would make for an elliptical orbit?
One serious theory advanced for the creation of Earth's moon is that it resulted from a collision.
However matter would be thrown off in all directions and some will fall back. How could a mass of ...
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What is the minimum size to be a natural satellite?
Would a smaller satellite be more stable around a smaller planet where the same satellite would not be stable or last around a larger planet?
I added the picture to show how moon size planets can ...
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How long will a ball of ice stay in orbit around Earth? [closed]
How big would a ball of frozen water need to be to last one orbit? How would atmospheric drag effect the ball of water?
https://space.stackexchange.com/questions/32188/what-is-the-darkest-orbit-...
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Could a moon be passed from one planet's orbit to another?
Like if you had two planets that had a close orbital path could the moon be pulled away from the first planet?
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Can orbits change?
I was reading about how the planet Mercury changes its orbit. I was wondering if farther away planets, particularly ones with elongated orbits, could do that as well? Planets and objects such Halley's ...
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1answer
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Doing Correct Calculations with Binary Star Systems
I've been experimenting with Binary Star System calculations but came across some issues.
I can correctly calculate the Semi-Major Axis of the Earth's orbit around the Sun by doing the equation:
...
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1answer
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What is this elliptical orbit?
Most natural elliptical orbits are one sided as shown below from wiki.
What is an elliptical orbit where perigee and apogee are closer to being equal in distance than not?
I have learned that this ...
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1answer
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How far from the Sun can an Earth TCO (temporarily captured orbiter) go after leaving?
Objects which are temporarily captured into an Earth-Moon system orbit (temporarily captured orbiters or TCOs) by definition will leave this orbit. While the term suggest an Earth orbit, it's really ...
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1answer
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Problems with computing X,Y,Z positions of planets at a certain time in Unity3D (C#)
I'm trying to create a little program in Unity3D that positions the planets in 3D space at a given time. I've followed this document: http://stjarnhimlen.se/comp/ppcomp.html.
Using the data from ...
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1answer
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What is wrong with my calculations of Venus' orbital period?
I am trying to use Kepler's second law to find the duration of Venus's orbit. I am assuming circular orbits (using Earth and Venus, so low eccentricity). Here is my process:
Assuming that the radius ...
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1answer
670 views
Can one detect from earth that angular momenta of its axial rotation and its orbital rotation are “almost parallel”?
I mean that the angle between these angular momenta is acute as opposed to obtuse (23.5 and not 180-23.5), so that the rotations are "roughly in the same direction".
Related but distinct question -- ...
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1answer
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Why is the time between equinoxes different?
The path of the Earth around the sun is described as being an ellipse, with the Sun being at one of the foci of the ellipse.
Since an ellipse, by definition, is symmetrical with respect to the foci, ...
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1answer
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The specifics of two Earth-like worlds orbiting each other? [closed]
I'm currently looking into writing a story or two set on twin worlds, which I came to find out in my research is apparently not a new idea (Double planets?
Rocheworlds? Am I close?). But I want it ...
3
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2answers
75 views
Can a planet's changing tilt be aligned with the rotation around its star? [duplicate]
What I'm asking is if the tilt of a planet can "follow" the rotation around its star so that, for example, its north pole would always lean towards the star, and thus always be under daylight. The ...
2
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1answer
69 views
How dependent is Earth is with the other Planets' gravity? [duplicate]
How would the Earth be affected if the Moon was destroyed as far as our orbit around the Sun? What if Mars or Jupiter was destroyed?
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1answer
607 views
What is the Terra phase?
Does the Moon have a night and day like Earth? When sitting on the Moon and viewing the Earth what does it look like when the Earth goes through phases like the Lunar Phase? How does the sun travel ...
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Modeling planet rotations (time of day, obliqueness, etc.)
I created this solar system model using POV-Ray:
by following these instructions:
https://ssd.jpl.nasa.gov/txt/aprx_pos_planets.pdf
The next thing I want to do is orient/rotate each globe correctly ...
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1answer
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What percentage of the celestial sphere can the Moon cover?
I was solving a task that said (paraphrasing):
What percentage of the night sky can the Moon cover during the entire
year, when observed from all points on Earth (what percentage of the
night ...
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73 views
+50
How much magnetic attraction is there between the Sun and Earth?
How much magnetism is there between the Earth and Sun? Would the distance from the Sun differ for not the Earth iron core and how much?
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Table of dates for planet retrograde motion
Is there a table which shows the dates of the planets retrograde motion? I want to know at which date a certain planet will start the retrograde motion.
