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3 votes
4 answers
7k views

Does the Earth constantly lose mass?

Starship is go for launch
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21 votes
2 answers
4k views

What equation tells you how far in space you can go from a point and return?

Albert
  • 801
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?

Sir Cornflakes
  • 646
17 votes
2 answers
3k views

Why did Chandrasekhar use 2.5 for molecular weight in 1931?

Peter Mortensen
  • 255
14 votes
2 answers
3k views

How did asteroid (7482) 1994 PC1 get its "face"? Is it reconstructed from optical or radar imaging, or something else?

CommunityBot
  • 1
0 votes
3 answers
1k views

Do the inner-Earth planets actually align with the constellations we see?

Pierre Paquette
  • 6,071
13 votes
1 answer
2k views

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

James K
  • 104k
8 votes
2 answers
1k views

"Tidally locked" Oort Cloud object

James K
  • 104k
10 votes
3 answers
1k views

Can stars be born giants?

Oscar Lanzi
  • 393
14 votes
1 answer
2k views

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

ksousa
  • 1,047
7 votes
2 answers
3k views

Would it be possible for a planet to orbit around a trinary star system in a figure 8 orbit?

James K
  • 104k
7 votes
2 answers
1k views

Are main-sequence G9 stars habitable?

M. A. Golding
  • 6,572
4 votes
3 answers
1k views

How do I estimate the difference in the speed of time flow between Earth and a distant star?

Sten
  • 1,409
11 votes
1 answer
1k views

Did this satellite streak past the Hubble Space Telescope so close that it was out of focus? If so, how close was it?

Peter Erwin
  • 15.7k
7 votes
1 answer
764 views

How do I calculate the moment of the solstice?

Roy Smart
  • 711
3 votes
1 answer
347 views

Moon's equation of the centre discrepancy

David Hammen
  • 32.4k
3 votes
2 answers
318 views

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

PM 2Ring
  • 11.7k
8 votes
1 answer
218 views

Adhara ultraviolet magnitude

ProfRob
  • 132k
5 votes
3 answers
111 views

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

planetmaker
  • 14.3k
5 votes
3 answers
180 views

Why does the Milky Way look as though it's lit from one side?

ProfRob
  • 132k
2 votes
2 answers
75 views

Supernova remnant spectral lines

Grond
  • 41
3 votes
1 answer
181 views

Conditions in the Early Universe

Albert
  • 801
2 votes
3 answers
176 views

How to calculate distance between stars?

M. A. Golding
  • 6,572
6 votes
1 answer
142 views

How exactly is UT1 measured/calculated?

terry-s
  • 1,186
4 votes
2 answers
153 views

Numerical Programming using ODEINT takes more than 17 minutes

uhoh
  • 31k
1 vote
1 answer
150 views

Calculating the parameters of binary systems?

ProfRob
  • 132k
0 votes
1 answer
115 views

How certain is the Sun's classification?

planetmaker
  • 14.3k
4 votes
1 answer
142 views

Seeing exoplanets with glare

ProfRob
  • 132k
3 votes
1 answer
142 views

Outer Limit of Oort Cloud

Pierre Paquette
  • 6,071
3 votes
2 answers
81 views

Venus Atmosphere Color

Mikee
  • 41
2 votes
1 answer
120 views

Can the expansion of the universe cool my beer?

Sten
  • 1,409
5 votes
1 answer
91 views

What do the negative values in FITS images mean?

giardia
  • 1,989
0 votes
2 answers
101 views

Will the Milky Way galaxy revolve around the Andromeda galaxy or vice versa?

James K
  • 104k
1 vote
2 answers
73 views

Modified Julian Date (MJD)'s epoch is 0:00 on November 17, 1858 (JD − 2400000.5) has fewer digits than JD. But what's so special about November 1858?

David Hammen
  • 32.4k
3 votes
1 answer
91 views

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

Starship is go for launch
  • 199
2 votes
1 answer
90 views

How much of the variance of matter is due to scales

Sten
  • 1,409
2 votes
2 answers
129 views

At what point above Jupiter is the gravity Earth-like?

PM 2Ring
  • 11.7k
1 vote
1 answer
59 views

Moonrise and Moonset time in Sydney vs Perth

James K
  • 104k
4 votes
1 answer
158 views

CSPICE vs JPL Horizons discrepancy in AZ/EL

David Hammen
  • 32.4k
3 votes
1 answer
95 views

Size of the whole universe if it were spherical

Sten
  • 1,409
3 votes
1 answer
78 views

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

GrapefruitIsAwesome
  • 1,721
0 votes
0 answers
165 views

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

Clifford Lingwood
  • 49
1 vote
1 answer
70 views

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

uhoh
  • 31k
0 votes
0 answers
148 views

What do you call the opposite of a leap second?

Starship is go for launch
  • 199
2 votes
1 answer
69 views

Motion equation of a space engine in low-earth orbit

ProfRob
  • 132k
2 votes
1 answer
52 views

How can I get a list of the closest x stars and their distances from the Gaia ESA Archive using Python?

Roy Smart
  • 711
2 votes
1 answer
50 views

Sideways crescent moon in Maryland

Pierre Paquette
  • 6,071

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