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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11
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1answer
298 views

Why are all-Sky images drawn as a filled ellipse?

There is some convention? how is this 3d to 2d mapping done? here an example
2
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1answer
544 views

Astronomical detection significance from magnitude error

At this website: http://heasarc.gsfc.nasa.gov/docs/swift/analysis/threads/uvot_thread_afterglows.html The passage at the bottom states that a V-band magnitude of 17.62, with an error $\pm$0.02 is a ...
2
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3answers
143 views

Planetary Atmospheres

Venus (0.815 Earth mass) supports a CO2 atmosphere of 93 bars at its surface. Earth's N2/O2 atmosphere has a surface pressure of one bar. What are the factors that limit the mass of atmospheric gases ...
2
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1answer
283 views

What happend with the light from all the galaxies visibles from an earth telescope?

Supposing it's possible to see some distant galaxies with an earth telescope, then, at the tip of the telescope lens there are photons comming from the distant galaxy... So, if I extend my hand in a ...
3
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3answers
2k views

Why do stars have absorption spectra?

Absorption spectra are a result of light of a certain wavelength exciting an atom from a lower energy level to a higher one and at the same time being absorbed. However, the atom should eventually go ...
1
vote
1answer
195 views

Astrophysical Data

I am working on a project that requires some amount of number crunching. I require some basic data about the galaxy M82 and our own Milky Way (particularly luminosities). My advisor is a nut and he ...
2
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0answers
332 views

What is the name of the physical space enveloping all universes? [closed]

Please excuse my question, as i don't come from a physics background, but i was really wondering. Assuming we are in one of numerous universes which all have physical dimensions: What is the name of ...
4
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1answer
361 views

Exoplanet surface detail: Limitations on size of space telescope array

How big could an array of space telescopes acting as an interferometer be ? How big would it have to be to resolve exoplanet surface detail the size of Iceland at a distance of 100 light years ?