The science dealing with objects and phenomena located beyond Earth. In particular, this applies to observations and data. At its core, astronomy is the physically informed cataloging and classifying of the contents of the universe in order to better understand what is out there.

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Is there a confirmation of dark matter signal?

Dark matter, as we know does not emit light, so confirmation of its presence is indirect. Are there any recent indirect confirmations of dark matter. A place one would look for in detecting dark ...
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124 views

How did Kepler arrive at his laws?

How did Kepler arrive at his laws? If one already knows the distances to the planets (and the eccentricity of the orbits etc.) it is understandable how one might proceed to establish the second and ...
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61 views

Classification of small extra-solar system bodies

A Small Solar System Body (SSSB) is an object in the Solar System that is neither a planet, nor a dwarf planet, nor a satellite. This encompasses all comets and all minor planets, as well as all ...
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85 views

Is there a map which shows all the black holes in our galaxy?

I am looking for a map which shows all black holes in the Milky Way. See this exoplanet map for what I mean. If it is not existing (yet). Is there at least an online catalogue which summarizes for ...
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58 views

Import of Celestial Effects on Satellite Radio Interference

Some internet (among other) infrastructure comprises satellites, which beam communications in radio frequencies. These satellites, to ground observers, appear as very small solid angles in the sky. ...
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214 views

Analyse astronomical data

Recently I was told of a job offer to analyse astronomical data. The job offer states that they want somebody with knowledge of astronomical data analysis software and it will be a plus somebody who ...
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40 views

What is a geocentric altitude?

In NAO TN no.69, Yallop defines ARCV as geocentric difference in altitude between the centre of the Sun and the centre of the Moon for a given latitude and longitude, ignoring the effects of ...
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53 views

Is there uncertainity of position of the perfectly homogenous radiating body?

I heard the standard interpretation of Heisenberg Uncertainty Principle: Just the measurement affects the position of the body because always you want to see a body (=to measure the position), you ...
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81 views

Mass-to-light ratio and rotation curve from brightness profile

This should probably be basic but I've been looking for days and I can't find how to (I'm probably over complicating, but still). I want to calculate a rotation curve for some spiral galaxies. From ...
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24 views

Synthesising types of galaxies using various stellar spectra

I have been given the task of synthesising an elliptical galaxy, a starburst galaxy and a spiral galaxy (considering the arms and the bulge separately and adding them) using stellar spectra which I ...
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29 views

Luminosity, brightness and magnitdes in cosmology

I just started learning Cosmology and am confused with these terms. What I know so far: Luminosity $(L)$ is the energy output (inc. visible light, radiation etc.) per unit time of a star. It is an ...
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26 views

How much cheaper and smaller on average is SiPM technology over conventional PMTs?

I've heard it said that some of the major advantages of silicon photomultipliers are its low cost and compactness when compared to widely used photomultiplier tubes, but haven't found much information ...
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72 views

Algorithm for calculating lunar crescent visibility

Is there a simple algorithm for predicting lunar crescent visibility. Simple enough to do with a calculator at least. Those offered in Meeus' Astronomical Algorithms are a bit too involving to do by ...
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80 views

Simplified calculation to find Lagrange point L1

I'm trying to find the position of Lagrange point L1 in the earth-moon system. To make the whole thing easier (I thought) I don't care about the sun's influence or any other forces than the ...
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24 views

Calculating distance to a binary as well as star pair in cluster, based on reference star data of related spectral class

The problem at hand consists of calculating the absolute magnitude $M_V$ for a B0V type star, then the distance to a binary system with one star A1V and one B0V type star, and finally a star pair ...
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31 views

Recommendations regarding high-energy astrophysical objects (AGNs, jets, etc.)

I know basic astronomy and I know a few good textbooks for general astrophysics (eg. "Introduction to Astrophysics" by Carroll and Ostlie). I also have a strong background in theoretical physics and ...
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58 views

Why are other universes in the picture of Dark Flow?

It seems to me that the popular suggestive explanation of dark flow is another universe interacting with ours. Isn't there other alternative explanations?
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162 views

How fast do large asteroids usually travel?

I have just watched this video made by discovery channel, and you can hear the narrator at 0:51 saying that : "even though it is moving at 720 THOUSANDS kilometers per hour..." I stopped once I heard ...
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177 views

Reference request: Hollow concave Earth hypothesis

Reference request concerning the Hollow concave Earth hypothesis. I am searching for this paper: A Geocosmos: Mapping Outer Space Into a Hollow Earth authored by M. Abdelkader and published in ...
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109 views

Mass loss rate of planetary nebulae

The “interacting wind” model of planetary nebulae is based on the idea that the white dwarf phase of stellar evolution is preceded by a red giant phase. A fast wind from the hot white dwarf overtakes ...