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1500 questions
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Parking a telescope at a Lagrange point: is this a good idea from a debris point of view?
The James Webb space telescope is supposed to be located at the Earth-Sun L2 Lagrange point.
Do we expect the region around that point to have a higher concentration of space debris, asteroids, dust, etc...? Would this be a matter of concern for…
FrenchKheldar
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Why is there so little nitrogen in the Martian and Venusian atmospheres?
Why don't our neighbors have much nitrogen? You would think that, without 'nitrogen-fixing' organisms and such, there might be more.....
Kurt Hikes
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What is the difference between gas and dust in astronomy?
Is there a strict difference between gas and dust?
In Earthly environment most things become gaseous if heated enough. The temperature of interstellar medium seems to range mostly between 10 and 10 000 Kelvin. Is gas/dust an analog for hot/cold, or…
LocalFluff
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Is there an upper limit on the mass of black hole mergers we can detect?
From the LIGO website, black hole mergers have been observed between black holes with a mass up to roughly 50 $M_\odot$.
Are there no black holes with a mass above 100 $M_\odot$ or is this an observational bias? Why haven't we observed any mergers…
usernumber
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How small can a spiral galaxy be?
The smallest observed spiral galaxies I can find are NGC 2976 and NGC 4605, both with a diameter of 20 kly, but I don't have anything like an exhaustive source to search. I've also found a mention that the Small Magellanic Cloud (7 kly diameter)…
Elukka
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What causes fast moving pulsars to move so fast?
This article investigates the traces left in the ISM by fast moving pulsars. Is there a mechanism specific to pulsars that causes them to move so fast, or are there just as many fast moving stars?
The article also mentions that
Many fast moving…
usernumber
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Are the stars distributed in uniform distribution, on the celestial dome, with respect to brightness?
Has there ever been a statistical analysis of the distribution of stars in the sky (on the surface of the celestial dome), by brightness? I want to know if they are uniformly distributed.
For example, all stars with Apparent Magnitude from 1.0 to…
DrZ214
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Why can't supermassive black holes merge? (or can they?)
The CNet article Astronomers discover two supermassive black holes in a death spiral links to Discovery of a Close-separation Binary Quasar at the Heart of a z ~ 0.2 Merging Galaxy and Its Implications for Low-frequency Gravitational Waves…
uhoh
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Why did this meteor appear cyan?
A meteor recently flashed over Queenland.
The meteor has been described by various people as appearing cyan or aqua, so the blueness of the image can't be due to a camera issue. The colour doesn't appear to be anything found along the black body…
Ingolifs
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Can a magnetic field of an object be stronger than its gravity?
Can a planet, star or otherwise have a magnetic field that is stronger or have more range than its gravity?
Muze
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Apparent Ring of Craters on the Moon
I saw this picture on the BBC news website.
There appears to be a ring of craters in the center of the picture, aligned in an approximate sub vertical orientation.
Am I just seeing things or does this apparent ring of craters a feature and does it…
Fred
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What are Kepler's laws (as he wrote them)?
There are of course many, many sources that quote Kepler's laws of planetary motion. This is preventing me from finding out what I really want to know: which is - what are Kepler's laws as he wrote them? As opposed to how they may have been later…
ProfRob
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Why did the distribution of asteroids discovered in 2010 have a radial modulation?
This answer links to one of Scott Manley's excellent asteroid videos Asteroid Discovery - 1970-2015 - 8K resolution. The animation highlights the positions of the meteors at the moment of their discovery, and by watching one can see the technology…
uhoh
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Is it "weird" that all disc galaxies rotate once every billion years?
In a recent paper (Cosmic clocks: A Tight Radius - Velocity Relationship for
HI-Selected Galaxies by Meurer, et al.), it was noted in the conclusion that:
[This] implies a constant orbital time of ∼1 Gyr at [the outermost] radius [of disc…
called2voyage
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Is Sun a part of a binary system?
Does our Sun have a counterpart, i.e., is it a part of a binary-system? If so, how does the other star look like and where is it?
stp30
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