Questions tagged [orbit]
Questions regarding an object 'falling around' another object, due to a combination of gravity and momentum.
2
votes
1answer
44 views
How can the oblateness of Earth impart torque to change the longitude of ascending node of a satellite?
I've read that you can change the longitude of ascending node of a satellite (i.e. changing the orbital plane without changing the inclination) to change its orbital plane by using the torque imparted ...
2
votes
1answer
67 views
Why is true and average anomaly of planet important?
Why is a true and average anomaly of the planet important? What useful information do they give us?
0
votes
1answer
40 views
If a solar system were surrounded by a cloud of debris, is it possible for a planet's orbit to intersect it?
I'm doing research for a story that I'm writing and I'd like some physics advice on whether a hypothetical system of celestial bodies is possible.
Suppose the following:
A system of planets orbiting ...
3
votes
2answers
88 views
Where will the planned Deep Space Atomic Clock orbit “after” Earth? [closed]
I've seen multiple sources repeat the information that the Deep Space Atomic Clock will 'at first' orbit Earth, before moving on out of Earth orbit.
The Deep Space Atomic Clock (DSAC) is a ...
2
votes
0answers
38 views
How to write a normalized, dimensionless form of Binet's relativistic equation?
$$\frac{\delta^2 u}{\delta \theta^2} + u = \frac{\mu}{h^2} + 3 \mu u^2$$
This is Binet's relativistic equation. Here $u = 1/r$ where $r$ is the radial distance, and $\mu$ is the reduced mass of the ...
2
votes
0answers
71 views
Orbital decay of the Earth's orbit and Earth's moving closer to the Sun
If we consider orbital decay of the Earth's orbit, then can we counter argue with the following reasons?
Due to tidal effects transferring small amounts of angular momentum from the Sun's spin to ...
1
vote
0answers
31 views
To show perihelion precession motion of Mercury in Python with matplotlib
I'm trying to make it more general code so I can trace even a parabola or hyperbola for $e=1, E=0$ and $e>1, E>0$ respectively. And after achieving that general code I want to make the same code ...
1
vote
0answers
27 views
What maintains the high orbital eccentricity of many exo-planets near their sun?
Over the last decade we've discovered that many exoplanets not only have highly eccentric orbits, but also orbit very close to their sun. This is true of many classes of stars.
I definitely have a ...
1
vote
2answers
200 views
Does the sun have cycles causing temperature changes on Earth?
Can the Sun go through seasons or cycles to cause a temperature change?
Could the Sun have to go through any kind of thermal cycle to change the climate on Earth and by how much?
2
votes
2answers
248 views
What is the coordinate acceleration for pure radial motion?
As seen in this answer and also in this book chapter 6, page 6-10 expression 22, when you are falling in radially from being at rest at infinity your velocity in coordinate time, as seen from a ...
13
votes
2answers
2k views
Is it possible to do moon sighting in advance for 5 years with 100% accuracy? [duplicate]
It is Ramzan and the usual heated disagreements between clerics here in Pakistan as to the sighting of the crescent. This time the minister of Science and Technology (who is not a scientist himself ...
2
votes
1answer
129 views
Why hasn't the Earth fallen into the sun yet?
So the Earth's been orbiting the sun in a relatively stable orbit for billions of years now. during that time, it's been plowing through dust, and hit by comets and asteroids, presumably mostly from ...
0
votes
1answer
95 views
Could the Sun have liquid iron in orbit?
How close of an orbit to the Sun could an iron meteor get before it melts into a ball?
3
votes
1answer
115 views
Did the Moon ever approximate a geosynchronous orbit above the early Earth?
Simulations suggest the early Moon formed about 20,000 to 30,000 km away from Earth which is less than the current geosynchronous orbit of 42,164 km. The Moon is now 384,000 km away from Earth. Does ...
1
vote
0answers
23 views
Are circumbinary and noncircumbinary habitable zones mutually exclusive?
Could a binary star system have an earth-like planet orbiting star A, a second earth-like planet orbiting star B, AND a third earth-like planet in a stable circumbinary orbit? Or does the space that ...
3
votes
1answer
71 views
Is there an optimum orbit for a hipparcos/GAIA-like parallax observatory
The GAIA spacecraft is currently mapping the stars in the Milky Way by parallax. It orbits in the Earth-Sun L2 lagrange point. The parallax observed from the spacecraft orbiting around the sun allows ...
2
votes
2answers
161 views
'Geocentric' view of orbits
Given our real solar system how would planet orbits plot look like if we fix earth in the middle (put earth in the middle and draw a real orbit of a given planet) ?
What would be the shape of its ...
1
vote
1answer
70 views
Earth orbit around the Sun and its position in the Galaxy
Given the orbit of the Earth around the Sun and the position of the Sun in the Galaxy, in which season are we (the Earth) closer to the galactic center?
1
vote
3answers
122 views
What orbit is the smallest or takes the least time to complete?
What orbit in our solar system would take the least time to perform 1 orbit?
What is the fastest possible orbit to complete in the universe?
4
votes
1answer
76 views
What is the closest an asteroid or comet has passed the Sun and survived?
After SOHO began watching the Sun from space with its coronagraphs 24/7 it was discovered that there are comets passing very close to the Sun quite regularly, and while some are destroyed, some are ...
2
votes
1answer
101 views
How far does the Earth travel around the Sun during each month of the year?
After reading about the Earth's orbit and how it moves faster in January than it does in July (based on its distance from the Sun), I started to wonder...
How far does the Earth travel around the Sun ...
2
votes
0answers
44 views
Why is the moon drifting? Shouldn't orbital decay bring it closer? [duplicate]
I noted that the moon drifts away from Earth a few centimeters each year.
However, I'm thinking that the emission of gravitational waves would deter such thing and cause the exact opposite. ...
2
votes
1answer
58 views
Various moon orbits
Orbits can follow certain patterns, as I am aware. Some include a circular orbit around the bulk of the planet, a polar orbit spinning about the pole...
What I'd like to know, for a planet with two ...
2
votes
1answer
92 views
Does the Sun twinkle?
Does our solar system have enough bodies in orbit to appear to twinkle to another distant solar system viewed from the side?
https://en.wikipedia.org/wiki/List_of_asteroid-discovering_observatories
...
6
votes
1answer
68 views
Can the moon's gravity influence be observed on the space station's orbit?
In browsing through Astronomy Stack Exchange, I came across this question about orbiting the moon (Is it possible to achieve a stable "lunarstationary" orbit around the moon?). In further ...
2
votes
1answer
79 views
Could there be additional Neptunian satellites between Larissa and Hippocamp?
Plotting the moons of Neptune in terms of semimajor axis and eccentricity using the values given on the Wikipedia page for the moons of Neptune, there appears to be a fairly large gap between the ...
2
votes
1answer
102 views
How come the Sun does not make the Moon crash on the Earth?
As the Moon loops around the Earth, on one side of the Earth it moves toward the Sun (let's call it downward side) and on the other side it moves away from the Sun (let's call it the upward side).
...
30
votes
2answers
4k views
Is there any known moon of a moon? [duplicate]
As far as I understand, a moon is an object in permanent orbit around a planet, dwarf-planet, asteroid, etc. If there was another object permanently orbiting this moon, would that be a moon-moon?
Is ...
3
votes
1answer
232 views
Can a photon have a stable 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 ...
2
votes
1answer
69 views
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 ...
3
votes
2answers
96 views
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 ...
2
votes
1answer
154 views
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 ...
5
votes
2answers
127 views
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 ...
4
votes
2answers
95 views
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 ...
1
vote
1answer
65 views
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 ...
5
votes
2answers
168 views
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 ...
1
vote
1answer
63 views
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 ...
1
vote
1answer
123 views
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 ...
1
vote
2answers
125 views
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 ...
7
votes
1answer
350 views
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 ...
0
votes
1answer
39 views
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 ...
2
votes
1answer
85 views
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 ...
2
votes
3answers
94 views
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 ...
7
votes
1answer
202 views
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 ...
0
votes
1answer
45 views
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 ...
8
votes
1answer
68 views
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 ...
1
vote
0answers
37 views
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 ...
2
votes
2answers
65 views
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 ...
1
vote
0answers
39 views
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 ...
1
vote
0answers
45 views
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 ...
