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Top Questions

30 votes
1 answer
5k views

Trying to identify something I saw in the sky

27 votes
1 answer
5k views

Why is the summer solstice night shorter than the winter solstice day?

13 votes
2 answers
4k views

Why are asteroids so much richer in precious metals than Earth's crust?

8 votes
3 answers
2k views

Planets looks like normal stars when I see them using telescope

10 votes
2 answers
1k views

JPL Horizons - "highly accurate measurements of planetary positions" - how do they do it?

19 votes
1 answer
3k views

Has the small meteorite that hit Webb done a lot of damage?

6 votes
1 answer
1k views

Finding Scorpio in the Milky Way panorama

7 votes
3 answers
662 views

How can I calculate an orbital elliptic trajectory from the velocity vector?

4 votes
1 answer
2k views

What does "to within less than about thirty Schwarzschild radii" mean?

4 votes
1 answer
2k views

How sure are we about the speed of light in vacuum in deep/far space?

11 votes
1 answer
1k views

What are those stars that cross the galactic center?

9 votes
1 answer
546 views

What does "Effective radius of [CII] line is 1.4 kpc" mean?

8 votes
1 answer
824 views

Binoculars 10x50 in light polluted place

11 votes
1 answer
788 views

Early Milky Way depictions after Herschel?

9 votes
1 answer
514 views

What unit of year in JPL Small-Body Database Lookup?

5 votes
2 answers
838 views

What does "by an amount" mean here?

7 votes
3 answers
201 views

escape velocity of leaving the Milky Way galaxy vertically and horizontally

3 votes
2 answers
473 views

Is this scaling of JWST halo reasonably correct

4 votes
1 answer
330 views

What does using these units (c=G=M=1) in MHD simulations mean?

4 votes
1 answer
362 views

Virial theorem, contraction, and stars getting hotter

5 votes
1 answer
193 views

Reason for different surface temperatures of Tau Ceti and Epsilon Indi at similar properties

5 votes
1 answer
154 views

How many stars can we resolve?

-2 votes
1 answer
114 views

Wouldn't the 1054 supernova have temporarily enlightened the Earth like the Sun?

3 votes
1 answer
197 views

When exactly was the last time that Earth's aphelion coincided (within 24 hours) with the northern winter (December) solstice?

2 votes
2 answers
119 views

Measuring distance to stars - How to get parallax angle

1 vote
1 answer
141 views

Should we fear Wolf-Rayet WR-104?

1 vote
1 answer
83 views

following several unknown phenomena detected at the edge of the solar system, is there a 5th force which acts at the edge of the solar system?

6 votes
2 answers
72 views

In terms of results, how similar is a bunch of telescopes across the globe to an Earth-sized telescope?

1 vote
1 answer
128 views

Distribution function for distance to nearest stars from any given star in our galaxy

2 votes
2 answers
69 views

How to find the first Julian day with the same Earth-Sun constellation

0 votes
1 answer
68 views

Do we get shortest shadow of any object at Solstice time or Meridian time?

4 votes
1 answer
83 views

Stellar evolution temperature gradient - why the logarithm?

3 votes
1 answer
79 views

Is V616 Monocerotis the closest black hole?

4 votes
1 answer
60 views

What does it mean that the radial coordinate becomes the time coordinate behind the horizon?

2 votes
2 answers
98 views

What is stopping Event Horizon Telescope the size of the Earth’s orbit?

-1 votes
1 answer
75 views

How to calculate metallicity of a star that is made of iron of 20kg and Hydrogen 1000 kg?

5 votes
1 answer
58 views

What kinds of stars have viable habitable zones other than G-type stars, and what would life be like orbiting them?

3 votes
1 answer
92 views

Does "Angular Diameter Turnaround Point" solve the Great Wall Problem?

1 vote
2 answers
86 views

Could primordial black holes explain the SMBH in the galactic centers?

3 votes
1 answer
60 views

Is the dark matter/baryonic matter ratio the same in galaxies with supermassive black holes?

3 votes
1 answer
57 views

How can the upper limit for a star's mass be calculated?

2 votes
1 answer
71 views

Celestial coordinates of every pixel in the image

0 votes
1 answer
91 views

What's the proper shape of a black hole?

2 votes
1 answer
67 views

What exactly causes "color twinkling" and why does it seem that any color might be furthest refracted for a moment?

1 vote
1 answer
58 views

redshift puzzle

2 votes
1 answer
58 views

What criteria determines whether stars are supernova type II candidates?

7 votes
0 answers
91 views

How are the occurrence and nature of micrometeoroid impacts on JWST optics identified?

2 votes
0 answers
114 views

Order of magnitude of this phase space invariant?


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