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1500 questions
18
votes
1 answer
Are Buckyball-sized black holes possible?
The first item is the basic question; the subsequent items build upon it if it's possible. If these need to be broken into separate questions, I can do that, but they're pretty tightly related.
Is a non-rotating negatively-charged singularity…
RoUS
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18
votes
2 answers
Moon orbits crossing each other
Some planets, such as Mars, have 2 or more moons. Giants, like Jupiter of Saturn have a lot of moons!
How likely the orbit of one crosses another one's orbit? Is it possible for two moons to collide? If yes, what would exactly happen?
Zoltán Schmidt
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18
votes
3 answers
What is the estimated density of the dark matter?
What is the estimated density of the dark matter? Some clumps of dark matter might have higher density and others might have lower density. So what is the estimated density range of dark matter?
Is it possible for clumps dense enough like for…
Joe Jobs
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18
votes
3 answers
How is asteroidal rock formed?
So when planets form, dust from the protoplanetary nebula gets collected by gravity and then heated and reformed under pressure until it forms dense masses of stuff which we call rock.
However, asteroids don't have nearly enough gravity to do this,…
David Given
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18
votes
4 answers
Jupiter FM - What are practical and inexpensive ways for the amateur detection of signals from Jupiter, especially of the transit of her moons?
What modifications to a standard AM/FM or shortwave radio are needed in order to be able to detect radio-wave signals emitted from Jupiter?
Would it be possible to detect the transit of the major moons and even minor planets (maybe even Ceres and…
user8
18
votes
2 answers
Why do the Pleiades look clearer when viewed indirectly?
I've noticed that the Pleiades look bright in the sky, but when I look directly at the constellation, it suddenly goes dim and it's more difficult to make out the individual stars.
Why does this happen, and is there a way to "beat the system" by…
brentonstrine
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18
votes
2 answers
What are practical considerations for backyard radio-astronomy detection of black holes?
Evidently, direct observation of a black hole for an amateur astronomer, such as described for what professionals do in the question "How are black holes found?" would be nigh on impossible, so the observations would be based on their effects of the…
user8
18
votes
3 answers
How are constellations intact if the stars are rotating around galactic nuclei?
From what I understood, the Milky Way (or stars in the Milky Way) doesn't rotate like a collection of points in a disc due to the presence of some invisible matter. In theory, the angular velocities of all the stars should be the same while linear…
Muhammed Roshan
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18
votes
8 answers
Are there places in the Universe without gravity?
Not sure if that is possible as I couldn't find an answer about it.
Are there places in the Universe where there are no gravitational forces?
Eric Cartman
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18
votes
1 answer
Where on Earth could dinosaurs feel the impact of their extinction asteroid?
Did the possible Chicxulub asteroid impact around 66 million years ago that made the dinosaurs and many other species extinct, cause the Earth to wobble? How large was the area, where they could "feel" the impact's consequences?
Peter U
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18
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2 answers
Why isn't most hydrogen in the universe molecular (diatomic), instead of atomic (monoatomic)?
Similar questions have been asked before; but, why?
Is the monoatomic hydrogen left over from the Big Bang? And hasn't had the opportunity to collide with other hydrogen atoms yet?
Or are hydrogen molecules that do form split up after absorbing…
Kurt Hikes
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18
votes
2 answers
How can astronomers pinpoint the location of the source of a neutrino?
In the popular press, in recent months, we have heard a lot about high-energy neutrinos from far outside our solar system reaching our detectors....
But I wonder...
If a single neutrino from a great distance randomly, rarely, smacks a xenon atom in…
Kurt Hikes
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18
votes
3 answers
What practical considerations are there for amateur observations of transiting exoplanets?
Obviously, I am not referring to actual viewing of the exoplanets themselves, but detecting their effects on the brightness of the light emitted from the parent star (as in the diagram below from The Institute of Astronomy, University of Hawaii). …
user8
18
votes
6 answers
If the Sun disappeared, could some planets form a new orbital system?
If the sun were to suddenly disappear, the planets would continue to travel tangentially to their former orbits. (This I know from this answer to a somewhat related question here.)
In such a scenario, is it possible (however unlikely) that a new…
Psychonaut
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18
votes
1 answer
How can a supermassive black hole be 13 billion years old?
A supermassive black hole was discovered recently that is 13 billion years old. This blackhole is 1.6 billion times the mass of the sun. How can this blackhole have formed so quickly after the big bang? Do theories predict supermassive black holes…
Natsfan
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