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1500 questions
24
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2 answers
Can a planet in our system eclipse the sun as seen from another one?
When the Sun, Earth and Moon get properly aligned, we get eclipses, where the Sun is partially or totally hidden by the Moon when seen from Earth.
Is it possible for one planet of the solar system to produce an eclipse on another one?
There are two…
jcaron
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Are there lightning bolts on Mars?
Although the Martian atmosphere is thin, there are many atmospheric phenomena that occur on Mars: storms, dust devils, (carbon dioxide) snow,... Some storms even stir up the atmosphere of the entire planet!
During Martian storms, is there any…
usernumber
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24
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1 answer
How long between the moment a meteor is first visible and the moment a meteorite hits the ground?
A meteor is usually only visible for a couple seconds at most, but I would guess that it usually stops being visible high above the ground.
Meteors often don't make it to the ground as they completely burn up before. But among those that do reach…
usernumber
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24
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3 answers
Why is the Moon's orbit so complicated?
I like to think I have a good enough understanding of astrophysics but there's still one thing that I just can't explain.
Why does the Moon orbit the Earth the way it does?
Many other moons in the Solar System orbit their planet along the equator…
ChristieToWin
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24
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1 answer
Why are there so few supernovae in M31 (Andromeda)?
Estimates of the supernova rate in the Milky Way put it at a few per century, but very few of these are visible from Earth (at least with the naked eye) because of intervening gas and dust clouds). On the other hand the Andromeda galaxy (M31) is…
Steve Linton
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24
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1 answer
Why does the sensitivity to GWs drops off inversely proportional to the distance?
This answer makes me wonder why the sensitivity to gravitational waves decreases proportionally to the distance.
Since gravitational waves extend in all directions, my (uneducated) guess would be that the same argument can be made as for the…
usernumber
- 17,492
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24
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4 answers
Why can't we feel the Earth's revolution?
I googled it and checked a few Q&A and there's only things about "Earth's rotation". But why can't we feel the revolution?
They say we can't feel the rotation because the Earth spins at a constant speed. Okay, I get what happens for the rotation,…
dolco
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24
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6 answers
Why do galaxies collide?
If the universe is expanding outward, what is the processes for one galaxy to get off track enough to collide with another?
Say, the Andromeda Galaxy and the Milky Way.
Dave
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24
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2 answers
What detail can Hubble see on Mars?
I'm researching a scene for a sci-fi novel in which the near-future protagonists observe earth through a station-mounted telescope in Mars orbit. My goal is to understand how much detail they reasonably could discern.
The Hubble telescope is…
Eric J.
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3 answers
What (the heck) is a Super Worm Equinox Moon?
Google News feed shows me the following.
What does the term "Super Worm Equinox Moon" mean and has it ever been used before this 2019 clickbait instance?
uhoh
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Can the Moon eclipse Venus?
The title basically says it all. As seen from the Earth, is it possible for the Moon to eclipse Venus (or any other planet) or are the orbits inclined such that this never happens?
If such an eclipse is possible, is it a frequent or infrequent…
CatchAsCatchCan
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4 answers
Metallicity of Celestial Objects: Why "Metal = Non-metal"?
Metallicity of objects refers to the amount of chemical elements present in it other than Hydrogen and Helium.
Note: The other elements may or may not be actual metals in the true sense of their defintion.
But why did astronomers use such a term…
MycrofD
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24
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2 answers
What is the formula to predict lunar and solar eclipses accurately?
A number of ancient civilizations had devised methods to predict exact dates and times of such eclipses, marking them as important events.
Hence I assume the predictions were based on calculations, which should be quite easy to do now.
So what is…
eminemence
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24
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4 answers
What is a singularity? What is at the center of a black hole? Specifically regarding space-time
So because I can only really think of space-time in 2-dimensions like a sheet of something, my assumptions might be wrong to begin with. I was watching a YouTube video on black-holes and there was a quip regarding black holes and their warping of…
gigatexal
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24
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5 answers
Is it possible that all dark matter is made of rogue planets (free-floating planet)?
Is it possible that all dark matter is made of rogue planets (free-floating planet)? (and other stuff like asteroids or meteoroids)
Clausia
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