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

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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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40 views

Does tidal heating imply orbit degradation?

What compensate the energy loss in tidal heating? Is it orbital decay?
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29 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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45 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
138 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 ...
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42 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
205 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
53 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 ...
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31 views

Review Content for my Comet Infographic

I've been hard at work in recent months on an infographic that details the anatomy of a comet... I'm a graphic designer and this is a fun little side-project of mine. It's only quite basic in terms of ...
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1answer
44 views

Orbiting and landing on non-sperical objects

If we orbit a non-spherical asteroid or moon at a sufficient distance I believe that we can consider it to be a point mass. Therefore we can take up a conventional orbit. Assuming our lander craft is ...
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2answers
58 views

How common are exoplanets in distant orbits?

Are there many single transits in the Kepler data, which might be exoplanets with a longer orbital period than the time they have been observed for transits? Can any conclusions be drawn about how ...
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1answer
109 views

Is it possible to create a traditional clock solar system?

Is it possible to create the following system of satellites?: Place a satellite that orbits the some object X, once per day. Call it D. Place a satellite that orbits D, once per hour. Call it H ...
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69 views

Orbits in a binary star system

I know of three sets of stable orbits in a binary star system: orbiting closely around star A, orbiting closely around star B, or orbiting distantly around both stars (and their mutual center of ...
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591 views

Do all orbiting bodies eventually collide?

If two celestial bodies are in orbit, will they always eventually collide if not acted upon by outside forces?
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23 views

Linear motion in the equatorial frame

I would like to calculate how the RA/Dec changes when an object has an apparent linear motionin the equatorial sphere. For example, more or less what an artificial satellite would do in a circular ...
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76 views

Why are retrograde orbits more stable than prograde ones?

Regarding solar system dynamics, i.e. planets in stellar systems and moons in planetary systems, this is often mentioned in the literature, but it is difficult to find a good analysis/explanation of ...
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32 views

Are trojans in L5 more likely than in L4?

Mars has much more trojans in L5. Does it reflect a common pattern?
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12 views

Semimajor axis variations in co-orbital moons

I've been playing with simulations of co-orbital bodies similar to Saturn's moons Janus & Epimetheus- horseshoe orbits where the two bodies are of comparable mass- and I'm seeing some very odd ...
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1answer
49 views

How far away would a supernucleus comet be visible?

If an instrument like LSST quickly spots something as soon as it reaches magnitude 24½, how far away would a 60km first-time visitor from the Oort cloud be when it is spotted? I'm thinking that a ...
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1answer
47 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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224 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
43 views

How do astronomers determine the texture of an exoplanet?

So I was wondering how astronomers are able to get the texture/detail of an exoplanet or how they know a planet has water or not. I know how they discover planets by using the light of a star and ...
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4answers
131 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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68 views

How to calculate geocentric conjunction time and moon altitude at a given time

Umm al-Qura calendar of Saudi Arabia determine the new moon if these criteria meet at 29th day: The geocentric conjunction occurs before sunset. The moon sets after the sun. I've got the formula ...
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1answer
120 views

Day Length on Double Planets

Assume two similarly sized bodies tide-locked to one another orbiting a barycenter between the two. That barycenter orbits a star. Since the two are tide-locked, their sidereal rotational period and ...
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1answer
88 views

Capturing Ceres

Would it be possible to slightly change the trajectory of Ceres to make it end up orbiting the Earth without messing up the Solar System? How much energy would be required and how long would the ...
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54 views

How much time comet is within the Earth's orbit? [closed]

Comet on the parabola orbit flies by Sun. I would like to know what is comet's full energy? What is its distance from Sun at perihelion?
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47 views

How to calculate full (mechanical) energy on the hyperbolic orbit?

For example, for a comet that travels on the hyperbolic orbit around the sun.
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93 views

For how many bodies can there be a stable orbit with no very heavy central body?

The question is a bit vague, but let me explain: Take for example 2 bodies of the same mass. They can orbit around their centre of mass/gravity. Is something like this possible with multiple ...
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27 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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59 views

What is the most populated/numerous stellar system in which the orbits of all objects are known?

I posed a question or two on here a couple months or so ago about the orbital patterns of each of the seven stars in the two septenary star systems Nu Scorpii and AR Cassiopeiae. They remain ...
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1answer
65 views

What are the equations for an orbit with time as parameter?

I am preparing a talk on the Equation of Time, and I want to produce an animation of the movement of the earth around the sun, in an exaggerated ellipse, to illustrate the speeding up and slowing down ...
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2answers
105 views

Is the North star going to stay in the North sky?

Considering how the our solar system, and how every other star in the galaxy is traveling through the cosmos, it seems like it's a miracle that the stars and constellations in the sky stay as constant ...
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1answer
69 views

Is there a theory / equation showing whether or not two passing bodies will go into orbit around each other?

I am looking for a theory that shows whether or not two passing celestial bodies will go into orbit. I assume there would have to be a critical point where the gravitational attraction is stronger ...
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2answers
104 views

How long for a complete solar system cycle

Considering the solar system as a closed system, how long until all the planets pass twice by the same position relative to each other? I would say that you'd have to get the length of the year in ...
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1answer
80 views

Does the Sun's light travel fast enough to have a straight path to Earth?

Hopefully this question isn't too silly. When we travel through space, we use a curved path following an orbit to reach our destinations. As far as I'm aware, we could take a more straight line ...
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Can we know the orbital planes of extraterrestrial planetary bodies?

Astronomers can tell if there are any exoplanets orbiting its parent star using but not limited to the following methods: Transit As an massive object usually a planet passing in front of a star ...
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1answer
51 views

What is the largest object on which the Yarkovsky effect has been observed?

The Yarkovsky effect is responsible for changes in the rotation and orbit of some celestial bodies, most notably asteroids. It has been measured on asteroids, such as 6489 Golevka and 1999 RQ36. What ...
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are all the planet in the same plane? [duplicate]

are all the planet in solar system the same plane in the space or not ? if yes is there any especial reason ? and if no how do they orbits then ? as far as i know they are in the same plane , but is ...
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55 views

Is there a threshold on distance/size for a tidal locking?

I know that some systems tend to tidal locking (such as earth-moon), which occurs basically because the difference in the gravitational pull on one side is significantly different from the pull on the ...
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1answer
196 views

Does our sun/solar system orbit around any other celestial objects? [duplicate]

Does our solar system orbit around another massive celestial object? Like a massive star or black hole for instance? From my understanding our sun rotates around the centre of our galaxy, thus our ...
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246 views

Is it possible that the Sun has a binary partner (the Nemesis Theory) that has eluded detection?

I just recently learned about the theory that our Sun has a small companion star with a 26 million year orbit. This theory came about when it was realized that mass extinction events happened ...
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26 views

Orbital resonances and position of planets

I am interested in quick generation of planetary systems for programs similar to Space Engine or Pioneer Space Simulator. As far as I understand, formation of planets is a complex process and the ...
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83 views

How do the orbits of Nu Scorpii and AR Cassiopeiae work?

I apologize for the way this question is worded but I don't think I know the proper verbiage. Basically, I want to know how the stars orbit one another in the two septuple star systems. For example, ...
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28 views

How to calculate the new orbit after a instantaneous change in a well defined initial one?

Say one has a simple two body system (and one body is much more massive than the other, for example a star, planet system) where all the quantities about it are know, that is the eccentricity, masses, ...
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91 views

How much light does Jupiter project onto the surface of Ganymede?

I suppose the answer would be a range as the Jupiter-facing side of Ganymede passed from Jupiter's light side to its shadow side. I'd also like to know how much light the sun projects onto the surface ...
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259 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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128 views

Shouldn't all moon orbits be inherently unstable?

A hypothetical simulation starts with a planet called Earth in a perfectly circular orbit around a star called Sol. There is also a moon called Luna in a perfectly circular orbit around Earth. ...
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3answers
151 views

Does the orbital variation in planetary gravity affect the Sun's corona

Dimitris (see below) argues that the syzygies of the Earth and Venus and those of Mercury, Earth and Jupiter distort the Sun's corona, which in some way affects climate on the scale of hundreds of ...
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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 ...