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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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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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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How strong are the stellar flares on YZ Ceti?
Doing research for a game and trying to understand the implications of the stellar flares from YZ Ceti. In short (ignoring the planets for now), if people were to build large space stations of various ...
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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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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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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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Question on dec 2013 answer to"How to measure the altitude and azimuth of a star?"
I am looking at your response to the above question. You stated:
For Northern Hemisphere, a star that is crossing the North local meridian (that is, between the Zenith and the North Horizon) the ...
user28084
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Does anyone knows the origin of the Maunder Minimum and Dalton minimum?
Solar spots seams to be a good indicator of solar activity. Does anyone know the reason for the Maunder and Dalton minima?
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Attempting to determine astronomy values in a parameter file
Recently I inherited quite a few old QuickBasic programs which perform various astronomical calculations. I'm attempting to understand these programs and rewrite some of them in Python. I do not ...
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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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