Dave
  • Member for 6 years, 2 months
  • Last seen more than 1 year ago
Is the moon "perfectly" tidally locked and, if not, how long would it take us to observe it's rotation?
11 votes

The Moon indeed "wobbles" about in its orbit because it goes around the Earth in an ellipse and not a circle. From our point of view, it wobbles a little back and forth such that over a lunar cycle, ...

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Why does Kepler's "Big Picture" of comet 67P look so strange? And what is the significance?
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11 votes

One thing to keep in mind is that the Kepler instrument is not a telescope like Hubble. It is a photometer and though it uses CCDs to look at the sky, it doesn't return a picture in the usual sense. ...

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How can we focus radio telescopes on a star when the earth is spinning?
6 votes

Because the speed of light is so much faster than the speed of the telescope, the star looks like it is standing still in the sky so the telescope only needs to track it as it moves across the sky at ...

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Why does the sun appear 13x bigger through diffraction in Voyager 1 image from 1990, but not from Earth?
5 votes

Don't base the size of the Sun on what you see in that image because the Sun is over-exposed. The big spot in the center of the diffraction spikes are saturated pixels because they all appear to have ...

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Array of telescopes with single orbiting collector?
4 votes

If I understand your question, what you're talking about is one of the things that has been on the astronomical wish list for ever. There are two ways to combine separated telescopes. One of them (...

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How does the solar wind destroy the atmosphere of a planet lacking a magnetic field?
4 votes

At least in the case of Mars, the solar wind carries a magnetic field by the planet. In the Martian atmosphere are ionized particles created from interactions with UV light, cosmic rays, etc. The ...

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How to calculate the mean molecular weight of the Sun
4 votes

For your second question, it depends upon whether you are talking about composition by number, or composition by mass (the numbers you give are roughly the composition by mass). If you want to get ...

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Conversion of magnitudes to Jansky and MAGPHYS?
4 votes

Caveat this with the fact that I am not familiar with this code. The input asks you for the flux through the filter, but a filter has a bandpass, so if you have a 10 nm bandpass filter and you ...

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Any new info about solar flares hitting the Moon added by the LADEE mission?
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4 votes

You'd probably be most interested in the results of the Lunar Dust EXperiment (LDEX). A 2015 paper states LDEX data show no evidence for an electrostaticallylofted dust component at densities ...

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Why can't we travel faster than light? And is the theory of relativity absolutely flawless?
3 votes

No scientist really considers a theory flawless, but as theories put together by mankind go, it is one of the best ones put out there. One of the things that makes for a great theory is not only ...

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Is a Gas Giant a Perpetual Motion Machine?
2 votes

You don't have a perpetual motion machine because you are losing energy to space in the form of heat, light, solar wind, etc. Even if you want to restrict it to the case where you are not expelling ...

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Need help with the math in Python program to flag Jovian radio emissions
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2 votes

There were a few other small errors in your translation (such as indenting too much stuff in two of the if statements), and I think you might have been trying to be too clever with changing SUBROUTINE ...

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Does this black hole magnetohydrodynamics equation even superficially make sense?
2 votes

I believe your assumption of the partial derivatives with respect to time being identically zero is incorrect. When you are talking about working in phase space, i.e., Liouville's theorem with ...

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Age of Occator Crater
2 votes

It seems not yet. The non-uniform density of craters seen on Ceres is still under investigation. From the abstracts of those papers, they're still working on trying to date the ejecta material from ...

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Is there a more modern/updated paper than Hurley's 2000 SSE?
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1 votes

My guess would be no because, as of this writing, from the paper link you provided you can see there are 949 citations to that paper with a good chunk of them in this year. You could always contact ...

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