All Questions
Tagged with fundamental-astronomy astrophysics
23
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How long would a day be in an earth like - same size and all - planet but with double earth's orbit in time
I'm a writer, so I apologize in advance.
On an earth like planet with and orbit double to ours in days, how long would days be?
My planet would take aproximately 672 earth days to orbit around it's ...
- 103
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37
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What is value of charge by mass ratio (q/m) for a spherical micro charged particle with surface potential 6 volts in S.I units and in e/amu units?
In Liu and Ip (2014),The Astrophysical Journal, 786:34 (8pp), the value of q/m is derived as follows :
"for a dust grain with radius 'a', from $\phi = \frac{4\pi q}{\varepsilon_0 a}$ we have $\...
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Do interstellar asteroids decelerate and eventually stop?
I do wonder, do interstellar asteroids eventually stop at one point in space after they gradually decelerate (or) even do they decelerate?
Though there is no air like on earth and thus asteroids ...
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474
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Necessary steps to calculate photon's path by using null geodesic equation
Can anyone please give me an explanation on how to calculate photon's path by using the null geodesic equation? N.B. I know all of the non-zero values of Christoffel symbols.
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568
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Any ideas for an astronomy + ML project? [closed]
I wish to do an astronomy related project which incorporates machine learning.Do you have any suggestions?
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1k
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How to find the radius of a satellite not knowing the mass
If I know the semi-major axis, the density of the planet, and orbital period.. how can I find the radius of the satellite? I can't think of any formula to use.
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What liquids can be found in the void space?
Is there any material natural or otherwise a free floating liquid that can exist in space?
https://space.stackexchange.com/questions/32274/what-liquids-last-the-longest-in-space
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What was the length of the solar day 73 million years ago?
How could this be estimated, or how accurately could it be extrapolated from a present-day measurement of the Earth's spin-down rate?
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Account for radiation energy in the statement "total energy of universe is zero"
I've read in Hawking's book The Theory of Everything that total energy of the Universe is zero. He explained this by saying that if there are two bodies separated by a distance and having some mass, ...
- 159
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1
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When black holes forms out of a supernova do they have a very high velocity?
When black holes forms out of a supernova do they have a very high velocity ?? Or do they remains at the position of parent star ??
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Flatness of celestial systems like galaxies and Solar System [duplicate]
If we look around the cosmos, we will see most of the systems are just flat disks. Either it is solar system, galaxies, or the rings of Saturn. What is the matter, does it depend on how they were ...
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What happens if one day aliens want to talk to us. How can we talk to them? [closed]
Always I wonder about that if some day alien wants to talk to us, then how can we talk to them? They didn't know any of the language on the Earth.
What will be the basic building blocks for it?
- 21
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1
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403
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What should I read next after Neil deGrasse Tysons "Astrophysics for people in a hurry"? [closed]
I really liked the clever way the author explained stuff in this book but I already understood most of it. Neil himself states in the book that if you are not in a hurry and want to know more about ...
- 21
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325
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How to know that the 21cm Hydrogen line is the actual emission and not any other redshifted line?
Is it possible that we mistake some other wavelength emission to be 21 cm because of redshift?
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Why the Hubble constant is so inconsistent?
Having a look on Wikipedia I noticed the following values (of the last 6 years) for the Hubble constant:
67.6±0.7 SDSS-III Baryon Oscillation Spectroscopic Survey
73.00±1.75 Hubble Space ...
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