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Top Questions

2 votes
2 answers
50 views

Finding the absolute magnitude of a star as a fraction/multiple of the Sun's absolute magnitude

2 votes
3 answers
202 views

Before the 1761 transit, what was our best estimate of the distance to the Sun?

6 votes
4 answers
1k views

Moving from mathematics to astronomy/astrophysics

5 votes
1 answer
321 views

Difference between fluid Love number and tidal Love number

1 vote
1 answer
64 views

Critical density of universe with intrinsic spatial curvature

2 votes
0 answers
34 views

Do brown dwarf 'stars' fuse simple hydrogen (p-p reaction) at all?

1 vote
1 answer
212 views

Does the expansion of space stretch the space-time fabric?

-2 votes
1 answer
145 views

What are the necessary steps required for calculating the size of a star? [closed]

3 votes
1 answer
91 views

Does syzygy mean only three aligned bodies, or at least three aligned bodies?

3 votes
4 answers
7k views

Does the Earth constantly lose mass?

1 vote
1 answer
46 views

How do I find out when sidereal time was 13:30 on a certain date and location?

5 votes
1 answer
185 views

Why is the difference from a perfect sphere the same for the Earth and the Moon?

1 vote
1 answer
23 views

What components (parts) are needed to connect telescope to DSLR?

0 votes
0 answers
18 views

Spacetimes where symmetries vary from place to place?

-1 votes
0 answers
36 views

Eccentricity with a law of gravity different from the classical one

1 vote
1 answer
70 views

Do astronomical datasets exist that receive duplicates or are there multiple datasets that contain the same entities (stars)?

18 votes
2 answers
6k views

Why is Venus's atmospheric pressure 75 times that of earth when carbon dioxide is only 1.5 times heavier than air?

0 votes
1 answer
43 views

I was searching position of Sirius star in stellarium app then i saw some weird shapes

1 vote
1 answer
33 views

How to calculate solar ecliptic longitude

0 votes
0 answers
148 views

What do you call the opposite of a leap second?

15 votes
3 answers
8k views

Is there a maximum size for a black hole?

4 votes
1 answer
452 views

Comoving distance between two points [(RA1, Dec1, z1) and (RA2, Dec2, z2)]

50 votes
7 answers
10k views

What is in the center of the universe?

0 votes
0 answers
165 views

where are we in the universe as compared to the observable universe? [duplicate]

2 votes
0 answers
43 views

How to convert GMST to GMST° (degrees) for calculating RA

2 votes
0 answers
74 views

Credible description of point sources and point spread functions in astronomy

1 vote
2 answers
66 views

How is Earth's Rotation Angle (ERA) defined and measured

1 vote
1 answer
50 views

Drawing stars in a 3D space

13 votes
1 answer
2k views

How would "dark matter", subject only to gravity, behave?

0 votes
1 answer
66 views

Are there non-smooth metrics for spacetime (that don't involve singularities)?

82 votes
2 answers
17k views

Could the dinosaurs have seen the asteroid that killed them?

6 votes
1 answer
142 views

How exactly is UT1 measured/calculated?

5 votes
3 answers
8k views

What should I consider in order to accurately calculate the moon phase?

7 votes
1 answer
764 views

How do I calculate the moment of the solstice?

2 votes
1 answer
50 views

Sideways crescent moon in Maryland

5 votes
3 answers
111 views

In layman's terms, why does the cold C-N-O process end in Carbon?

-3 votes
0 answers
82 views

What is the significance of the Cosmic Microwave Background Radiation (CMB) and how does it support the Big Bang Theory?" [closed]

0 votes
0 answers
32 views

What is the declination of the Sun as a function of its angular distance to solstice?

3 votes
1 answer
78 views

How (the heck) does an astronomical Celescope work? And how did it get its name?

3 votes
2 answers
318 views

How to find zero velocity contours for circular restricted 3-body problem in x-y plane?

0 votes
1 answer
69 views

Get (X, Y, Z) coordinates from Horizontal Coordinates

8 votes
2 answers
1k views

"Tidally locked" Oort Cloud object

2 votes
0 answers
28 views

What is the best estimate for the radius of Shoemaker-Levy 9?

14 votes
1 answer
2k views

Could it be possible to detect planets from stars that went supernova through the resulting nebula shape?

8 votes
1 answer
218 views

Adhara ultraviolet magnitude

10 votes
3 answers
1k views

Can stars be born giants?


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