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1500 questions
27
votes
2 answers
Why do the planets orbit in the same direction?
Theoretically, planets would have an approximately equal chance of going one way in their orbit or another but in reality, this is not the case (at least in our solar system). Why is this?
HotSaucey
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27
votes
5 answers
How does gravity really work
I am only 12 years old and I'm constantly wondering and trying understand how gravity really works. On YouTube everyone always talks about objects warping space time around themselves and uses the analogy of a trampoline. I still don't understand…
user11186
26
votes
5 answers
Does a planet's mass or gravity affect the height of it's mountains?
According to this Wikipedia page, the top five highest mountains on Mars (and the highest on Venus) are all taller than Mount Everest (and Mauna Kea as measured from the ocean floor).
Does a planet's mass or gravity affect the height of it's…
Fezter
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26
votes
2 answers
How did Kepler "guess" his third law from data?
It is amazing that Kepler determined his three laws by looking at data, without a calculator and using only pen and paper. It is conceivable how he proved his laws described the data after he had already conjectured them, but what I do not…
math_lover
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26
votes
3 answers
how far away could we detect that Earth has life?
My guess is that life bearing planets are too far apart to be detected. I think we can only find the ones within a sphere around our planet that is 100s of light years in diameter but I suspect life bearing planets may be much farther away than…
Software Framework
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26
votes
6 answers
Is the light we see from stars extremely old?
Our nearest star Proxima Centauri is 4.243 light years away from Earth.
Does that mean we are seeing light that is 4.243 years old everyday?
PrivateUser
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26
votes
4 answers
Is it coincidence that the earth's rotation and revolution are in the same direction?
In a reference system where the sun is static, the rotation and revolution of the earth are, when viewed from above the north pole, both counterclockwise.
Is it a coincidence that they agree? Or does the earth's angular momentum somehow "interact…
Marc Vaisband
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26
votes
6 answers
Definition of a moon in an exam: "A satellite of a planet that *doesn't produce light itself but reflects it*" - is there relevance for the emphasis?
In a 5th-grade exam (for 10-11-year-old pupils in Finland), there was a question, "What is a moon?" The model answer was: "A satellite of a planet that doesn't produce light itself but reflects it." Most pupils answered simply "A satellite of a…
tputkonen
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26
votes
2 answers
Why does the Earth have a tilt of ~23°?
Is there a reason that the Earth has the tilt that it does (~23°)?
How do we know which way is supposed to be 0°?
Does this tilt have major consequences on the planet?
Has it changed and will it change in the future? (If so, would there be any…
Jackson
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26
votes
1 answer
Why did Mars lose its magnetic field?
I had heard that Mars once had a planetary magnetic field, but that it is now gone? What happened to it?
Sarah Szabo
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26
votes
6 answers
What should I look for in a first telescope for a child?
I'm in a situation that I think many parents find themselves: my son has said that for Christmas he wants "a telescope so that I can see the planets". Which is cool, and I certainly would like to encourage him on this path. But what should I get?…
Vilx-
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26
votes
4 answers
Is there any planet bigger than a star?
Or a star smaller than a planet?
Which star and planet would be an example of this?
asker223
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26
votes
3 answers
Is Jupiter's Red Spot "locked in place" or does it move around?
A person could be forgiven when looking at Jupiter's Red Spot storm for concluding that it doesn't move. That it's geologically locked in place. But is it?
I know it's a stretch to use the phrase "geologically locked in place" when referring to a…
JBH
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26
votes
3 answers
Is the sun's volume shrinking currently?
The Sun loses about 5.5 million tonnes of mass every second, does this mean Sun's volume is also going down? If so can we tell by how much every year?
E:
"by how much" I mean can we tell if sun's radius is going down too
xenfoulis
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26
votes
3 answers
Why can't stars be multicolored like gas giants?
Gas giants like Jupiter and Saturn have bands of different colors in their atmosphere. These are due to the rotation of the planets. Stars rotate too, so why do most stars have patches/blotches of color rather than having latitudinal stripes?
harada
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