Questions tagged [fundamental-astronomy]
Questions involving reference frames, time scales, and how they are determined. Not for general Astronomy 101 questions.
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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 ...
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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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How is Earth's Rotation Angle (ERA) defined and measured
UTC typically ticks with TAI. But to keep UTC from drifting far from the rotation angle of the Earth we occasionally add leap seconds to ensure that UTC does not drift too far from the UT1 timescale. ...
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LSR and peculiar motion corrections to RAVE survey velocities
I am working towards getting a bunch of halo stars in our galaxy for my thesis. I am doing this with the help of a Toomre diagram and I am stuck. I am using the RAVE survey in conjunction with Gaia as ...
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On what basis is the information about the distance and velocity of the Voyager probes determined?
Voyager 1 was the first-ever object to reach interstellar space on
August 25, 2012 when it passed beyond the sun’s realm of plasma
influence (the heliosphere)[...]
(source)
Although some of their ...
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How does Polaris remain constant for millennia if the earth is spinning, orbiting and traveling with the galaxy? [duplicate]
Look at Polaris. Understand heliocentric theory and then reason.
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What is a "fundamental location", and why is Mosting A defined as one for the moon?
The crater Mosting A was chosen to be the "fundamental location" for the Moon's coordinate system (latitude and longitude). But what exactly is a "fundamental location"? What does ...
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How spaghettification is possible at the Event Horizon of a supermassive black hole?
if gravity is too strong then it will break a object apart as gravity is strong enough to break the chemical composition of object why we consider "Spaghettification" relevant in this case ?
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How can the IAU 2000A vs IAU 2000B nutation comparison be reproduced?
I am attempting to plot how the IAU 2000A nutation model degrades as its terms are omitted. As a spot-check, I decided to compare it to IAU 2000B, which includes only the 77 most important lunisolar ...
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Have there been studies of "old photons" to see just how constant things like Planck constant has been?
The question Are photons aged? and answers therein have got me thinking:
I vaguely remember hearing something about experiments where "old photons" were collected by large telescopes from very ...
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Difference between J2000, FK5 and ICRS coordinate systems? Which one does the Yale Bright Star Catalog use?
I have no background in astronomy. I have been wanting to write code to make star charts for a given location and time, which led to this question.
I figured out that I would need to convert the ...
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Why do astronomers use the equatorial coordinate system that moves, instead of one based on fixed, distant stars?
As an outsider to the field, I am surprised to learn that astronomers commonly use the equatorial coordinate system, in which fixed stars are not actually fixed.
Isn't that making life harder than it ...
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Is TDB monotonic? Does it or any of its derivatives have yearly discontinuities with respect to an atomic clock?
This in-depth answer mentions that
...TDB is updated every year. As technology improves, these subtle updates change the timing of past events.
This makes me wonder...
Does this updating result ...
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evaluate solar eclipse Besselian elements? [closed]
I found this NASA website which says that to predict eclipse, we should solve the Besselian elements ..what does this mean, how can I solve for Besselian elements? Is there a numerical method? I need ...
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Can a magnetic field of an object be stronger than its gravity?
Can a planet, star or otherwise have a magnetic field that is stronger or have more range than its gravity?
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