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Top Questions

0 votes
0 answers
16 views

Why are what end up being meteorites not in stable orbit as planets and large asteroids are?

0 votes
1 answer
65 views

Why not building a swarm of space-telescopes?

-1 votes
0 answers
23 views

I try to do a record today, into a video game called no men's sky, it's a space simulation. how old would I be after 100000 light years in 1h? [closed]

10 votes
2 answers
973 views

Why haven’t we observed supernova events of the hypothetical population III stars?

5 votes
1 answer
76 views

Do “neutrino supernovae” exist?

5 votes
1 answer
46 views
+100

What does it mean for something to be optically thick to pair production?

2 votes
0 answers
43 views

What would be the noticeable effects (if any) if the Earth's orbit entered a chaotic trajectory?

12 votes
1 answer
1k views

Is the scaling in this composite photo of the moon and the Andromeda galaxy reasonably correct?

22 votes
4 answers
5k views

Are there exoplanets as large as the star they orbit?

1 vote
1 answer
61 views

Are there tidally locked bodies where the "far side" is denser?

0 votes
0 answers
35 views

What are flux letters mean ? (U, B, V, R, I, G, J, H, K, u, g, r, i, z)

2 votes
0 answers
27 views

How do neutron stars maintain inhomogeneous surfaces and migrating "hot spots"? (e.g. SGR 1830-0645)

5 votes
2 answers
276 views

How could I see Andromeda as large as in this picture?

4 votes
2 answers
159 views

How to find the resolution of a spectrum?

0 votes
0 answers
19 views

Is it coincidence that the change in GPE when falling from deep space into the largest know neutron star is approximately mc squared Joules?

0 votes
1 answer
84 views

Celestial Coordinates and Sun's degrees below horizon

1 vote
1 answer
51 views

How do we measure the current positions of galaxies?

0 votes
0 answers
26 views

When will be the next visible Supernova? [duplicate]

2 votes
1 answer
15 views

Where can I find data on SDSS filter profiles?

1 vote
0 answers
18 views

Does cosmic inflation spawn from empty space, or vice versa?

10 votes
2 answers
865 views

Why is the ring in this simulation of Sgr A* off center?

15 votes
3 answers
6k views

What is the **actual** average distance of the Moon from Earth?

5 votes
1 answer
50 views

What is the spectral reflection curve of cold white dwarfs and neutron stars?

3 votes
1 answer
56 views

When were Swift and Voltaire discovered?

7 votes
1 answer
319 views

Is this image of Sgr A* correctly labelled?

-1 votes
0 answers
20 views

If two object moving away from each other, does one object see the other slower than their relative speed? [migrated]

3 votes
0 answers
70 views

Does the presence of dark matter in the Milky Way significantly distort our parallax based measurements of distance?

8 votes
1 answer
219 views

Is the appearance of accretion disks of M87 and Sgr A* in EHT image, related to the nucleus being active or non-active?

1 vote
1 answer
72 views

How far above the galactic plane would a telescope array need to be in order to image the whole galaxy?

1 vote
2 answers
71 views

What object(s) are furthest above/below the galactic plane?

3 votes
0 answers
52 views

How are plage regions related to the density of medium and velocity FeII ions?

1 vote
1 answer
72 views

What is the "sunrise equation" for non-constant declination component?

0 votes
1 answer
63 views

What is the nearest synchronous twin star system? [closed]

1 vote
2 answers
129 views

Why do sunrise/sunset times (for a given location) vary based on the source of the data?

7 votes
1 answer
314 views

Should I drop source shot noise from the SNR calculation when all I care about is detection (not photometric precision)?

0 votes
1 answer
56 views

Are Right Ascension and Declination from an "inside" perspective?

3 votes
1 answer
85 views

Does the newly found orientation of Sgr A* match the theory that the Fermi bubbles might have been caused by jets?

10 votes
0 answers
86 views

How bright would the night sky be in the galactic center?

0 votes
1 answer
44 views

Calculate how many days left for synodic period from particular planet

9 votes
2 answers
3k views

Why aren't reflector telescopes built with an offset secondary mirror?

2 votes
1 answer
74 views

Will Jupiter's days speed up?

1 vote
1 answer
27 views

SAO Encyclopedia of Astronomy information

5 votes
6 answers
222 views

Interpretation of Hubble constant in SI units

9 votes
3 answers
1k views

How time-symmetric is orbital mechanics?

5 votes
1 answer
192 views

Difference between NSBH and BHNS mergers

14 votes
2 answers
1k views

What determines the speed of a star's solar wind?


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