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3 votes
1 answer
73 views

What moons have cleared their orbits?

1 vote
1 answer
64 views

How is a planet (or star's) radius defined?

2 votes
1 answer
92 views

Could there be bacteria in the 6000 km water jet of Saturn's moon discovered by the James Webb telescope?

3 votes
0 answers
24 views

Why does the tropical year have a ~161 years cycle?

0 votes
1 answer
141 views
+100

how far can a gravitational-wave pass through space?

1 vote
1 answer
108 views

What is a place to find raw numbers of sunspots from the past, as counted daily by sun observer?

1 vote
1 answer
31 views

What are probabilities of finding a star with the specific stellar type?

1 vote
0 answers
6 views

How to obtain the SDSS’s five-part imaging ID number for a list of galaxies whose Ra Dec is known?

3 votes
1 answer
39 views

Detailed online catalog of astronomical objects?

0 votes
1 answer
48 views

When dark energy became significant 6 billion years after the Big Bang was there anything else of significance going on in the universe?

6 votes
1 answer
935 views

Why do some images depict the same constellations differently?

3 votes
1 answer
275 views

How does the number of CMB photons vary with time?

31 votes
1 answer
5k views

Why did it take so long to invent telescopes given glass was used 4000 years ago in Mesopotamia?

1 vote
1 answer
116 views

If phosphine gas is to be proof of life on a planet, shouldn't there be other gases too?

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