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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Requesting book references for a non-expert person with math background or just a non-expert person
I've just finished my masters degree (to be exact previous week ^_^). And I'm completing my collection of applications of my studies. During previous year I started reading about Robotics and Coding ...
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Open problems in astronomy that an amateur (with a PhD in some other field) would have a chance of solving?
What are some open problems in astronomy that an amateur would have a chance of solving? Suppose the amateur has a PhD in some other field, owns a basic telescope, a set of filters, diffraction ...
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How would the night sky look from inside a globular cluster?
When the weather is clear, we can look at the stars. And we normally would see several thousands of them, they all being more than a $\textrm{pc}$ away from us.
Now, there are globular clusters, ...
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Calculation of Horizontal Coordinates
Given a fixed coordinate location on Earth (i.e. a latitude and longitude), and a fixed equatorial coordinate location of a particular astronomical object in the sky (i.e. right ascension and ...
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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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Are there more stars than all the words ever spoken by humans?
A while ago I saw Neil deGrasse Tyson comparing the number of stars in the universe with the number of words spoken by all of humankind, ever since.
I realize both of these numbers are not strictly ...
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Equations for coordinates of solar system objects
I would like to write a program that visualizes the solar system. To do this, I would need equations for calculating the coordinates of each solar system object at a given time. Where could I obtain ...
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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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How to calculate declination of Moon?
Is there any way to calculate declination of Moon for any day?I'll subtract inclination of Earth on the ecliptic from the result. I'll get Moon's the shortest angular distance from Sun.
Thanks for all ...
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The Luminosity of two stars with same brightness but at different PC away
Stars A and B are both equally bright as seen from Earth, but A is 120 pc away while B is 24 pc away. Which star has the greater luminosity? How many times brighter is it?
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Why you use log to measure metallicity in galaxies?
For example, I saw the next expression for matallicity in a paper: $\log(O/H) + 12$.
I understand O/H is the O(Oxygen) to H(Hydrogen) ratio but why is there the number 12? And why the logarithm?
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Planetary reference systems and time
I am researching into how coordinate systems of solar systems objects are created by reading some of the reports written by the Working Group on Cartographic Coordinates and Rotational Elements (e.g. ...
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How many astronomers are there in the world today?
How many now living individuals have a PhD in astrophysics, or by some other definition can be reasonably classified as astronomers? I think Richard Feynman once said that only one in a million is an ...
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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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What do the months and hours mean in Tomas Filsinger's Map of The Universe
I have had one of these in my room for decades:
I don't have the booklet that seems to usually come with it, can someone explain to me what the months (with days below it) and hours mean? I imagine ...
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