Questions regarding an object 'falling around' another object, due to a combination of gravity and momentum.

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2answers
288 views

How to plot orbit of binary star and calculate its orbital elements?

I have a set of dates, position angles ($\theta$) and angular separations ($\rho$) for visual binary star. For example: ...
4
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1answer
173 views

Why are most planetary orbits nearly circular

In our solar system, with the exception of Pluto all planets follow a relatively circular orbit around the Sun, at the same inclination. They also all rotate in the same direction, none are ...
3
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1answer
152 views

Could a habitable satellite of a gas giant have a stable subsatellite?

I have set a science fiction story on a moon, orbiting a gas giant (which orbits its star at approximately the same orbit as the Earth around the Sun), and given this moon its own satellites. The ...
3
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3answers
69 views

Are multiple satellites required to handle geostationary orbits?

Do geostationary satellites need to have the equator as the plane of rotation, and the earth's centre to be the centre of rotation? Can it rotate over, say, the Tropic of Cancer, focusing on a single ...
3
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1answer
101 views

Do all moons orbit their planets on the ecliptic?

Do all moons orbit their planets on the ecliptic? Do they all follow this same process as the moon that orbits Earth, or is their some random distribution with some even having extreme polar orbits.
3
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2answers
148 views

Why are spacecraft not air-launched from airplanes

I searched on the subject, thinking it could probably be cheaper to fly the spacecraft aboard a plane and then launch it from altitude. The only thing I found was this Wikipedia page, but it only ...
3
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2answers
92 views

Is there an orbit that could cause regular debris showers like in the movie Gravity?

[some spoilers] If you were in the ISS and orbiting the Earth roughly every 90 minutes, would it be possible for debris to be orbiting such that it passes you every 90 minutes? While Neil DeGrass ...
3
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1answer
953 views

Average amount of annual daylight at any place on earth

If this is the wrong group please direct me to the correct one. It seems intuitively obvious that the amount of daylight per annum should be the same for any latitude on earth. For example, 12 hours ...
3
votes
1answer
98 views

What is the optimal escape trajectory from near a black hole?

Consider a space ship that is being drawn closer to a black hole. The crew begins to notice the effects, and discovers that they are nearing the black hole. They then manage to halt their ...
3
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2answers
105 views

Apogalacticon and Perigalacticon

What is the length of the apogalacticon and perigalacticon of the Sun and Milky Way? The general terms seem to be apoapsis and periapsis. My greatest efforts at Googling have failed miserably. If ...
3
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1answer
650 views

How can I calculate the orbital periods in a binary star system?

I have two stars, with known masses and known orbital radius. How do I calculate the orbital periods of both stars?
3
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1answer
84 views

Can orbital migration cause a planet to crash into the sun?

If the planets move out of their current orbits into other orbits over long periods of time could this cause a planet to crash into the sun? Maybe the term crash is a little dramatic, could the orbit ...
3
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2answers
129 views

How fast is a comet moving when it crosses Earth's orbit?

Is it about the same as Earth's orbital speed?
3
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1answer
54 views

Sattelite's orbit

What is the maximum distance for a satellite to orbit the earth? Does earth's gravity has the impact on satellite? I do know that earth's gravity will never be zero and it's gravity is inversely ...
3
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3answers
336 views

Spotting the International Space Station (ISS)

Recently, I visited the NASA website which provides sighting locations to see the International Space Station (ISS). As we all know, we can even see ISS with the naked eye in a clear sky as a passing ...
3
votes
1answer
31 views

Determination of orbital elements for Trans-Neptunian Objects, how?

How are orbits calculated for Trans-Neptunian Objects? I understand there are six standard parameters for defining an orbit (link) but I am not sure how telescope observations translate into these ...
3
votes
1answer
50 views

Leonid meteor showers and the Tempel-Tuttle comet

I've been reading about the Leonid meteor showers and am struggling to understand one piece of information. On Wikipedia (Tempel-Tuttle), it states: The orbit of 55P/Tempel–Tuttle intersects that ...
3
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1answer
115 views

Where did this famous Planetary Precession Formula come from?

The following equation (which I shall term the Planetary Precession Formula, PPF for short) famously appeared in a 1915 publication by Einstein where he indicated how it could be derived from his ...
3
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1answer
46 views

Is there online data on asteroid axial tilts?

I am hoping to find axial tilts for asteroids and also their spring and fall equinox. Some of the asteroids I'm interested in are: 4 Vesta, 1 Ceres, 24 Themis, 65 Cybele, 153 Hilda, 624 Hektor
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3answers
310 views

Circular orbits

First of all, I'm studying orbits for a hobby: world building. Unfortunately, my mathematical abilities approach a ridiculous low threshold, which means I am stuck with reading the simplest ...
2
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2answers
131 views

Are there any known objects in a “dual” tidally locked orbit?

Is there any known pair of objects tidally locked with each other? I know the moon is tidally locked with the earth (e.g. one side always facing earth), but I don't know of any pair of objects that ...
2
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2answers
67 views

Birthdate differences calculation relative to earths orbit duration

I have got a question as i am trying to figure out what the real difference between the birthdate of my friend and me is. I am born on 1983 6th February 7 am. My Friend is born on 1984 7th February 1 ...
2
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2answers
63 views

Is there a lower limit for the altitude of orbiting objects?

As I understand it, one object can orbit another at a variety of altitudes, and the stability of the orbit is determined by (among other things) the speed of the orbiting object. Go too slowly and ...
2
votes
1answer
133 views

What is the orientation of planetary orbits?

I'm working on a planetary motion simulator. I've been working through the equations anomaly, eccentricity, etc. The one thing I'm curious about is if all the ellipses are oriented the exact same way ...
2
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1answer
104 views

Ramifications of black hole stellar system

Recently, I got around to seeing the movie Interstellar. In it, the characters of the movie visit a stellar system that appears to be built around a black hole instead of a star. On top of this, their ...
2
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1answer
46 views

Is axial tilt direction correlated with semi-major axis direction?

Earth comes closest to the Sun every year around January 3. Winter solstice is at 21-22 December, merely some 12-13 days away. That means projection of Earth rotation axis onto the plane of its ...
2
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2answers
89 views

Satellite/Planetary Orbits

All planetary orbits contain 5 unusually stable points. These points are particularly important because they allow man-made satellites to orbit the Sun with a period equal to that of Earth’s. 3 of ...
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2answers
54 views

How do kepler orbits account for planetary migration?

This article got me thinking if kepler orbits explain how a planet moves in a solar system how can a planet migrate as explained in the article. At some point don't the kepler orbits must need some ...
2
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2answers
93 views

How do I calculate the positions of objects in orbit?

In a model of the solar system, given the Sun is at the point $(0, 0, 0)$, an given the six orbital elements for each object in orbit ($a$, $\epsilon$, $i$, $\Omega$, $\omega$, $M_0$), how can I ...
2
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2answers
136 views

Orbiting supermassive black hole or galactic center of mass?

One of the ways they measure the (supposed?) supermassive black hole at the galactic center of the milky way is to measure those tens of stars right at the galactic center that are orbiting what ...
2
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1answer
60 views

Calculate apsides without knowing eccentricity

How would one go about determining the apsides of an orbit, knowing only the current distance between the 2 bodies, the orbital velocity, and the period? Every formula I've seen requires eccentricity, ...
2
votes
1answer
213 views

What would be the dynamics of a double-planet system, similar to Earth / Moon, but with both bodies nearly Earth-sized?

Researching a sci-fi story involving a "twin-planet" system. Is such an arrangement (however unlikely) physically possible? And if so, must they be tidally locked with each other, similar to the moon, ...
2
votes
1answer
104 views

Derivation of the formula for longitude of ascending node for a satellite

I've been looking into the document IS-GPS-200H to understand how to calculate satellite location in the ECEF coordinate. I am having problem understanding the formula to derive $\Omega$, the ...
2
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2answers
30 views

Locate asteroid in asteroid belt

I was interested in tracking the orbit of 1986 DA. I couldn't find any resource when I looked. Just for fun, so any help appreciated.
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0answers
50 views

The tidal locking problem concerning Earth sized planets in habital zone around Red Dwarfs

Would twin planets orbiting around each-other present a solution to tidal locking of habitable planets in Red Dwarf systems. It's an awfully easy equation to set up....oh ok I'm fibbing I can't do it. ...
2
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1answer
718 views

In 2016, the summer solstice will coincide with a full moon. How often does this happen?

I found that the solstices work on a 400 year cycle based on this. I can't find anything similar for the lunar cycle. Is there a formula I can use to calculate the date of the full moon?
2
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0answers
72 views

How can I create tracks of the planet's orbits on my computer? [closed]

I'm wondering if there's any good computer software for tracking the orbits of planets over time. I like to see the orbit's trails against the sky background. I'd prefer something that's free and of ...
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5answers
155 views

Can someone explain a Geostationary Orbit in a simpler way?

According to Wikipedia (link), a geostationary orbit, geostationary Earth orbit or geosynchronous equatorial orbit (GEO), is a circular orbit 35,786 kilometres (22,236 mi) above the Earth's equator ...
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3answers
88 views

Would Pluto keep an orbit without its moon?

I haven't studied space that much, but I know that Pluto has very little gravity, but just enough to keep a human on its surface. Would Pluto keep a regular orbit around the sun without some extra ...
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2answers
87 views

Why Earth's perihelion occurs 3rd January rather than 1st?

Why Earth's perihelion occurs 3rd January rather than 1st January? Is there any effort to correct this discrepancy?
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3answers
60 views

State of the stars

This question may sound silly but I'm really not pretty sure whether the stars are rotating or stationary.If they are not rotating what makes them to be stable?
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3answers
92 views

Can planets inside the Earth's orbit around the Sun appear to undergo retrograde motion?

Retrograde motion is: The apparent motion of the planets when they appear to move backward (from east to west) from the direction that they move ordinarily with respect to the stars. Can planets ...
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1answer
98 views

Why planet's orbit is not perpendicular or random ?

Why planet's orbit is not perpendicular or random ? It always seems each planet is revolving on the same geometric-plane around the star.
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1answer
118 views

Can General Relativity indicate phase-dependent variations in planetary orbital acceleration?

In a previous question about differences in Newtonian and GTR gravitional force for the case of star-planet gravitational interactions an approximate relationship was noted between the expressions for ...
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2answers
87 views

Is there a standard mapping of symbols to terms for celestial and orbital mechanics

Is there a standard mapping of symbols to terms for celestial and orbital mechanics (and physics in general)? For example here are some ambiguities Angular Momentum: L, H, J, $\Gamma$, Orbital ...
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1answer
66 views

Finding the radius of an eccentric orbit at any point

Knowing the apoapsis, periapsis and therefore period of an orbit, how can I find the radius of an object in an orbit at a given angle or time, whichever is needed. For example, if I have an object m ...
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1answer
67 views

Orbital Elements Transformations

I'm a third year undergrad, and for the project I'm doing this summer, I need to figure out the Earth's position and velocity from the moon's point of view. From the reading I've done, it seems like ...
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2answers
53 views

Do origin theories imagine each planet to first orbit the Sun very irregularly before stabilizing?

What I was wondering is that, for example, toss a few balls into zero gravity space randomly, what would be the steady state motion? Would not all the balls go on weird directions and undergo ...
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1answer
59 views

Question: calculating orbit using another orbit

A satellite which is moving around a planet of mass $M$ in a circular orbit of radius $R$ is given a sudden thrust into the center of the planet, so that it deviates an angle $a$. Find the ...
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2answers
84 views

What is the orbit of Earth around the Sun?

According to wikipedia and other sources, a planet and a star always move in a circular orbit around the common center of mass of the both bodies, in case of Earth and sun, this center of mass lies ...