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

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How to get the longitude of the perihelion to find the Heliocentric Equatorial coordinates of a planet

I'm writing a program to randomly generate star systems and I have been having a difficult time figuring this out. I've found the equations I need to get the heliocentric equatorial coordinates, but I ...
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2answers
107 views

Can planets have orbits other than elliptical or circular orbits?

Can planets have orbits other than elliptical or circular orbits? All of the planets in our solar system have either a circular orbit or an elliptical orbit (perhaps like Pluto).
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1answer
77 views

How to cool down a moon?

I'm doing an Astronomy project and need to terraform a moon. It is about the size of Mars and orbits a gas giant which is at a distance of 1.28 AU of its star. I though about putting a sunshade at the ...
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3answers
3k views

What if Earth and Moon revolved around each other like Pluto and Charon?

What would be different for us if Earth and Moon revolved around each other like Pluto and Charon do?
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1answer
117 views

Simulate an orbit with orbital elements

I want to simulate the orbits of the planets from our solar system. I want to use orbital elements to calculate the current position(xyz) at a time t. The simulation doesn't have to be too exact, but ...
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1answer
87 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, ...
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2answers
167 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 ...
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1answer
95 views

Ambiguity in Earth's “Tilt”

It’s well-known that the axial tilt of the Earth (with respect to the ecliptic) is about 23.4 degrees. However, two angles is needed to specify the orientation of any rigid body, so it’s unclear to me ...
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1answer
142 views

Can a star orbit around multiple planets or a planet with massive moons?

Note: I'm not talking about a star orbiting around a single or lonely planet :) I know a star orbiting a planet is almost impossible because if a planet is more massive than a star, that "planet" ...
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2answers
88 views

Alignment of Semi-Major Axis of Orbits

So I'd like to ask whether the semi-major axis of planetary orbits are aligned? Logically, they shouldn't be, but many websites act as if they are. If they're not aligned, what's the angle between the ...
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1answer
51 views

How (un)stable are the Lagrangian points 1, 2 and 3?

A couple questions, please: I know that the Lagrangian points 1, 2 and 3 are unstable and special Lissajous orbits plus some station-keeping are required to place a spacecraft around them. But I was ...
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1answer
38 views

Why do spectroscopic binaries have approximate circular orbits?

So for an assignment I have to answer the question what I can conclude concerning the shape of the orbit, knowing that it is both an eclipsing and spectroscopic binary. Now, I think the answer I ...
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2answers
754 views

When was the term “orbit” (in the modern sense) first used and by whom?

Wikipedia coyly suggests that some notions and views kept circulating (apparently since Adam and Eve) until finally Kepler, of all people, ... etc. I find this hard to believe. Please elucidate.
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1answer
62 views

Is the size and heat of a star important in the development of a solar system?

How do the size and heat of stars affect development of solar systems and what kinds of planets can develop? Is it possible to orbit supermassive stars? Furthermore, would star's unleashing violent ...
3
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1answer
108 views

Does the Sun orbit the Milky way in a (kind of) flat or inclined orbit or more of a sine wave? [duplicate]

I know it can't be a perfect ellipse or smooth orbit due to all the matter in every direction, and our Sun could be affected by a gravity assist of sorts if it passes close enough to another massive ...
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2answers
193 views

Precessing of the Earth

It's been known that the Earth's axial tilt varies from 22.5 to 24.5. Does this result in a wobbling while the value of the tilt varies about these two limits? If so, how does it affect the mechanics ...
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2answers
133 views

Stellarium 0.10.4: planet orbits change over time?

If I draw the orbit of Mars in stellarium 0.10.4 for 23 Sep 2015, it passes south of Chi Leonis: If I advance the date to 17 Oct 2015, however, the orbit of Mars correctly goes right through Chi ...
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4answers
553 views

Moon's orbit around the Sun

The Earth revolves around the Sun and the Moon revolves around the Earth. Out of curiosity I started thinking about the orbit of the Moon around the Sun and expected (assumed) it to be as follows: ...
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2answers
49 views

Two body transient solution

In the two body problem, if each body is given an initial condition as a momentum vector, what is the transient part of the solution as it settles into the steady state orbit?
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1answer
160 views

Best approximation for Sun's trajectory around galactic center?

What is the current best approximation for the path the Sun takes around the center of the Milky Way? I have found some information on the approximate position of the Milky Way's center, the speed of ...
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1answer
67 views

Do orbital resonances always form naturally?

For example, if I throw two planets to orbit a star at random direction, would they form an orbital resonance?
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1answer
241 views

How long does it take Dawn to orbit Ceres?

I haven't been able to find the orbit time of Dawn around Ceres. Do you know how long it takes?
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1answer
114 views

What is meant by matter distribution?

Frustratingly, I find this could be a very simplistic question and may leave me feeling a little stupid for asking it. But I have to ask this. My lecturer keeps refering to "matter distributions" for ...
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2answers
130 views

Could an asteroid knock the moon out of its orbit?

As describe in this CNN article, an asteroid is going to pass near the Earth on Halloween. The article says that As it misses Earth by about 300,000 miles (slightly farther away than the moon), ...
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5answers
485 views

Does the Sun turn around a big star?

The moon turns around the Earth. The Earth turns around the Sun. Does the Sun turn around a big star? If so, does this big star turn around a very big star? ... etc ... What are all the intermediate ...
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5answers
908 views

When will all eight planets in our solar system align?

Ignoring expansion of the universe, entropy, decaying orbits, and interference from any bodies colliding with or otherwise interfering with their orbits, will the eight planets known planets in our ...
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2answers
67 views

Can a probe orbit Pluto given Charon's gravity?

Is it possible for a man-made probe to orbit Pluto given its closeness to Charon? The gravitational field interaction of Pluto and Charon is likely to make simple orbit structure difficult for a ...
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1answer
83 views

What causes objects to become tidally locked?

I'm trying to write a gravity simulation (suns planets etc), and was hoping tidal locking could be one feature demonstrated. Using a simple equation for gravity has produced some interesting results, ...
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0answers
125 views

Is there a web service providing orbital data of solar bodies (planets, comets, asteroids, dwarf planets)?

I would like to be able to connect to a web-service and retrieve JSON data containing information on current (as of today or so) orbits of planets, comets, asteroids, and dwarf planets in our solar ...
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3answers
770 views

How does a gravity slingshot actually work?

From what I know of elliptical orbits, an object speeds up near the periapsis and slows down at the apoapsis, much like we learned in high school physics how a sphere would roll down and back up a ...
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1answer
176 views

How is it that all planets (and moons) in our solar system are in equilibrium orbits?

Previously, I was told that in order for any bodies to orbit each other for over a long period of time, the orbital period, distance and masses have to be precisely matched such that the bodies won't ...
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1answer
5k 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 ...
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4answers
492 views

Does Sun have a reflection on Earth?

The new Google Maps1 presents an actual view of Earth, with the current position of Sun illuminating half part of Earth in real time. It is quite an exquisite view. My question is based on the ...
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1answer
56 views

How to get from the earth to another planet/ the moon? What happens on the way? [closed]

I have a problem explaining for my students how to get from the earth to the moon? Is there someone who can give a good explanation? I Think these are words that might be included. Escape velocity, ...
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1answer
161 views

Should a station in orbit around the Sun travel in the same or the opposite direction to the planets?

If we put a station in orbit around the Sun, and wanted to send transports as regularly as possible without the travel costs being prohibiting; should we have it rotate around the Sun clockwise, or ...
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1answer
124 views

Is there a general term for epicycles, deferents, and eccentrics in Ptolemaic astronomy?

According to Ptolemy's (c. 150 CE) account of the motions of planets, planets moved in circular paths ("epicycles") around center points that in turn moved around the center of the earth along a path ...
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4answers
2k views

How can we avoid needing a leap year/second?

Given the Earth's current speed around the sun and current rate & axis of rotation, what is the best way to keep time to avoid a leap year? How many hours should we have in the day and days in a ...
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2answers
183 views

How many satellites orbit the Earth? At what rate do they orbit the earth? [closed]

I was looking at a full moon the other night with my telescope and noticed a black dot move across the moon quite rapidly. This happened a few times and others who were with me were able to confirm. ...
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1answer
88 views

Can Pluto and Neptune collide anytime in future? [duplicate]

We know that, the orbit of pluto ambiguously cuts the orbit of Neptune. I want to know, whether the revolving speed of Neptune is equal to the revolving speed of pluto. If not, is there a possibility ...
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1answer
139 views

What does the orbit of multiple star systems look like?

How can I find simulations of trinary, 4-nary.. etc. star systems? What do they look like? For example the Alpha Centauri system has 3 stars and possible planets. What does that orbit look like? I ...
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1answer
174 views

Venus presents same face toward Earth at closest approach. What do you make of that?

Is reference 6 in this Wikipedia article "dubious" and this passage in need of excising or clarifying? Venus's 583.92-day interval between successive close approaches to Earth is equal to 5.001444 ...
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1answer
105 views

Supermoon Lunar Eclipse?

I recently read this article: http://www.cbsnews.com/news/supermoon-lunar-eclipse-coming-this-month/ I'm having some trouble understanding how a "supermoon" lunar eclipse is possible. Judging from ...
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1answer
653 views

When will the next summer solstice and a full moon coincide? What day?

What day will the summer solstice and full moon coincide? As far as I know the next time will be in 2016. I would like to know what day.
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1answer
64 views

Does tidal heating imply orbit degradation?

What compensate the energy loss in tidal heating? Is it orbital decay?
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1answer
61 views

How is the heat production inside moons compliant with Conservation of Energy?

A Nova episode said that during stages of some moons' elliptical orbits, the moon is stretched, and friction causes the inside of the moon to heat up. I do not understand how this is compliant with ...
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2answers
172 views

Why do objects all orbit in the same direction?

In a solar system or a planet that has many moons, why do their orbiting objects all orbit in the same direction? Is it possible for two orbiting masses to orbit in the opposite direction of each ...
3
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2answers
169 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 ...
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1answer
474 views

Earth Rotation and Orbit Geometry

Let Line A be the projection of the axis of Earth's rotation onto the plane of the eliptic. Let Line B the line connecting the center of the Earth and center of the Sun. At what times during the ...
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2answers
302 views

Is the ratio between earth's distance from the sun and the speed of light just a coincidence?

I was doing some calculations to see how hard it would be to observe the speed of light and discovered an interesting correlation between the speed of light and the average distance from the earth to ...
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1answer
193 views

What is exactly the “longitude of the perigee”

Some moon phase calculation algorithms (apparently derived from Duffet-Smith's book, example here) seem to use a parameter called "longitude of perigee at epoch". What exactly is this? Can I assume ...