Questions regarding the attractive force which exists between any two bodies of matter.

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Are white dwarves supported by proton degeneracy as well?

In general, fermions form a degenerate gas under high density or extremely low temperature. It's clear that white dwarves are supported by electron degeneracy pressure. However, there are still a ...
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1answer
45 views

Why don't globular clusters flatten with a galactic disc?

Globular clusters lie in the galactic halo, outside of the disc. However, galaxies are more or less a collection of material and objects — why is it, then, that most stars form a plane due to the ...
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1answer
58 views

How close would merging black holes have to be to feel gravitational waves? [duplicate]

Recently LIGO discovered gravitational waves caused by two black holes that were orbiting each other, and then collapsed into one black hole. A few months later, we find out that this actually happens ...
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3answers
104 views

Precision of geocentric gravitational constant

I am looking for an answer as to why the geocentric gravitational constant, μ, defined as the product of the gravitational constant, G, and the mass of a body (earth in this case), M, can be ...
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6answers
2k views

Why are stars so far apart?

So, this is mere musing, but it seems that stars are quite extremely far apart. I tried to determine the mean distance between nearest neighbors for stars (in just our galaxy) but I'm not sure what it ...
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2answers
2k views

What would happen if Jupiter and Earth were at the same distance as the Moon is from Earth?

If Spock came with a super machine capable of moving planets, and placed Earth so close to Jupiter as the Earth's moon, the gravity of Jupiter would make us fall into it?
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1answer
119 views

A phonecall inside a blackhole

I was wondering what a phone call would be like entering or falling t=into a black hole. Due to the massive density of the black hole and time would feel slower, how would that appear to the person on ...
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2answers
94 views

Could this three moons system be stable?

In my fictional world I have selected all parameters to maximize the Hills Sphere of my planet. The planet has three times Earth's mass and it is located in 2 AU from its star that's 1.4 times more ...
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2answers
162 views

Is it possible for a moon to continuously have a side facing its star whilst orbiting a planet?

For example; is there any possibility for the moon to always have a side facing the Sun whilst orbiting Earth? And if so then what would the day cycle be like?
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Are a white hole's forces completely opposite of a black hole? [duplicate]

Would not all the forces of a black hole be opposite if the light is escaping from it? For example, rather than it attracting everything to it, would it repel everything?
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2answers
112 views

Techniques for locating origin of gravitational waves

The gravity wave detections (GW150914 and GW151226) have both been ambiguous in their exact position, the LIGO papers (GW150914 and GW151226) give no precise information about the location of the ...
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1answer
78 views

Can a gas giant be hollow?

Let's think of Saturn, because of its density. Can there be a place near the center of the planet where the gravity upwards is more than towards the center, and with an atmosphere that is more ...
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2answers
84 views

Higgs Bosons in the centre of Black holes or extremely large stars [closed]

With the discovery of the Higgs Boson as the mass carrier, what is the possibility at the centre of a black hole being so dense and gravity so infinite that the structure of a proton or neutron are ...
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1answer
58 views

Would the (orbitting) speed of the earth change if suddenly the sun disappear and the earth is thrown into space?

Usually an orbit is considered as an acceleration. So fe the earth has a speed of about 100.000km/h around the sun. Now I think there is some relativity involved, so from which point of view shall we ...
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2answers
109 views

Could asteroid mining affect gravitational balance?

I'm just a guy who is interested in all topics around space, so forgive me if it is a dumb question. I have read some things about asteroid mining in the past and I think it's a really interesting ...
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0answers
57 views

Theoretically could the expansion of the universe affect acceleration due to gravity?

I was wondering if theoretically the universe expanding affects speed or acceleration due to gravity, compared to if space weren't accelerating. The way I have it in my head, something is falling ...
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2answers
169 views

Can I leave a planet without achieving escape velocity?

I know that if you exceed orbital velocity, you will never fall-back to the planet. My question is not about orbits. It's about brute-force propulsion to achieve altitude. I'm using an ...
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1answer
111 views

LIGO gravitational wave chirp signal frequency

This question is about the LIGO gravitational wave signals' frequency. The signals start from about 35 Hz to peak at about 250 Hz, giving evidence of gravitational waves. The question is about the ...
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0answers
25 views

Where is Luna 1? [migrated]

Luna 1 was the first attempt by the Soviet Union to crash land into the surface of the moon but narrowly missed after a programming error becoming the first man-made object to escape Earth's ...
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1answer
915 views

How can neutron stars have gaseous atmospheres?

Neutron stars can have small atmospheres. However, they also have extremely strong gravitationally pulls. Shouldn't the all the gas molecules be drawn to the star's surface, and become solids under ...
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2answers
132 views

any unique phenomenon when the cores of two planets are aligned with their star's core?

Imagine a line passing through the cores of two planets (in the same planetary system) and their star. Have we ever witnessed this - either with both planets on the same side of the star or on ...
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2answers
4k views

Will Earth lose the Moon before the Sun goes into supernova?

Ive read on some sites and saw on youtube videos that the moon is getting away from earth by 1-3 cm a year. Is this enough to make the Earth lose the Moon before the Sun goes into Supernova? Im ...
2
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2answers
117 views

Solar Pressure and Gravity

I recently read some articles and pages on Solar Sails, and the possibility of using lasers to propel spacecraft, and I had a relatively outlandish idea. Would it be possible for a star to be ...
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2answers
274 views

Can the theory of multiuniverse explain dark matter?

If there are many universes they must have an gravity effect on each other. Since dark matter is measured through gravity but we dont know the mass behind it, isnt it possible that it comes from ...
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2answers
620 views

Why don't we orbit the center of our galaxy?

At the center of the milky way, there must be some giant mass that keeps the galaxy from just floating away from itself. So, obviously, we feel the immense gravitational pull of whatever this is. But, ...
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1answer
160 views

Could we verify the structure of a black hole by observing an orbiting object?

Can we determine the physical structure of a black hole by observing its gravitational effect on objects in orbit? There are three possibilities that I see, and would like to test: Singularity at ...
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0answers
47 views

Does a self-gravitating gas necessarily develop turbulence?

Though we may still doubt the exact driving mechanism of turbulence in each particular case (ISM, MC, circum-BH/-stellar discs, atmospheres...), can I say that in a sphere of dark matter particles no ...
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4answers
906 views

Is the influence of gravity instantaneous?

When I was in college, I posed to my astronomy professor a thought experiment that had been puzzling my mind for some time: "If the all matter in the Sun magically disappeared, instantly, how long ...
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1answer
57 views

Could gravity be the 4th dimension? [closed]

According to Michio Kaku, in his book Hyperspace, he said that in this Hyperspace, there exist a total of 10 dimensions that govern the laws of physics. Is it possible that we too live in a Hyperspace,...
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1answer
147 views

Why does Titan have lower surface gravity than the Moon when Titan is more massive?

Reading on Wikipedia I saw that Titan is 80% more massive than the earth's moon but has only 85% the surface gravity. Why is this?
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3answers
192 views

Is there any way a meteor can hit at less than escape velocity?

Note: I have figured out one case: The meteor is splash from an impact on a close-in moon. I'm looking for any path from deep space. My understanding is that anything from deep space will ...
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1answer
71 views

How much do the mascons on the moon affect surface gravity?

The gravity anomalies on the moon (generally accepted to be caused by mascons) are powerful enough to affect the orbit of satellites. I'm trying to determine how much effect they would have on a ...
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5answers
2k views

Does the gravity of the planets affect the orbit of other planets in our solar system?

When one planet passes near another during its trip around the sun, does their gravitational pull is strong enough to disrupt noticeably each other's orbit ?
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1answer
104 views

Satellite'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 ...
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1answer
1k views

Can dark matter be found in the shape of planets, galaxies etc.?

If dark matter has gravity just like normal matter, does that mean it can also form planets, solar systems and so on? Any answer will be appreciated.
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1answer
69 views

How does an absolute horizon form before the apparent horizon?

If I understand it correctly, the apparent horizon is the boundary between where light directed outwards will move outwards, and light directed outwards will move inwards. Even if light is moving away ...
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5answers
402 views

Could light be dark matter?

Is it possible that light itself is dark matter? I am speaking of photons (e.g. visible light, infrared, ultraviolet, etc...). I realize light is understood to be massless, but it is obvious it at ...
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1answer
52 views

gravitational time dilation multiple sources

I wondered how time would be dilated for an object in the middle of 2 black holes, however https://en.wikipedia.org/wiki/Gravitational_time_dilation only provides a formula for one source of gravity ...
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2answers
291 views

How can astronomers determine the difference between “hydrostatic equilibrium” and “just happens to be spherical”?

This is relevant for the definition of a dwarf planet. I presume the answer will be, well, if we can tell the mass of the body and guess the material. I don't find this very satisfactory because (1)...
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1answer
76 views

How does dark matter interact with black holes?

Is dark matter trapped near / in black holes, like regular matter is, or does something different happen with dark matter?
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2answers
3k views

Would time go by infinitely fast when crossing the event horizon of a black hole?

If you were to fall into a black hole, my understanding is that from your reference point, time would speed up (looking out to the rest of the universe), approaching infinity when approaching the ...
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1answer
103 views

Does Pi change when gravity changes [closed]

Will Pi have the same value on the surface of say Jupiter, compared to the value of PI on Earth. Or does Pi vary with gravity?
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2answers
30 views

How does gravity affect spacetime [closed]

Scientists say that gravity warps space and time. They also say that the more gravity there is the slower time moves. Why and/or how does gravity do this.
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5answers
6k views

How does gravity really work

I am only 12 years old and I'm constantly wondering and trying understand how gravity really works. On YouTube everyone always talks about objects warping space time around themselves and uses the ...
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2answers
433 views

What causes Earth's gravity? [closed]

Why Earth is like a magnet? how can earth attract any object irrespective of what it is made of? What is the reason behind Celestial Body's gravity? i.e Sun,Jupiter,Moon etc.
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1answer
108 views

How is mass curving spacetime?

In the GR Einstein's interpretation was in terms of a deformation of the geometry of the space ending in a curvature of spacetime. I've thought that mass could do this by interacting with other mass ...
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1answer
93 views

What star system/Galaxy did LIGO observe the gravity wave?

Are there any coordinates for the Black Hole system, or galaxy for which the LIGO observations, observed the gravity wave? Any coordinates of the black hole system for which the gravity wave signal ...
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2answers
3k views

Do all the objects in the universe exert force on all other objects?

Do all the objects in the universe exert force on all other objects? Like a type of gravity; also, how much does it decrease as it gets farther away?
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6answers
6k views

What did LIGO Actually See? (Gravitational waves discovery)

I am trying to find an original video/image of what LIGO actually saw, but all I can find is artist renditions of gravitational waves.
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1answer
64 views

When black holes such as those detected by LIGO merge, in what ways does the Schwarzschild Radius warp?

I was reading the paper about LIGO's detection of gravitational waves, and I wanted to know what the Schwarzschild Radius did. For example, I feel like the simulation here is oversimplified, and that ...