Questions tagged [spectroscopy]
Questions about the measurement of light waves whereby the wavelength is classified by its position in the electromagnetic spectrum.
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What does the ']' in the spectral line "CIII] 1909 Å" mean?
The above emission line, as I understand, is a useful probe of early star-forming galaxies.
However, I do not understand what the ']' to the right of the 'CIII' means.
I could not find any online ...
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At what speed does something have to travel away from us for it to red shift enough that it becomes invisible to the human eye?
Are there stars, galaxies etc that we cannot see because they are traveling too fast and their spectrum is shifted below our visible range? From what I understand, red shift is caused by stars and ...
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Redshifting restframe SED
I have a template spectral energy distribution (SED) at z=0. I want to shift the template SED to an arbitrary redshift (z>0), how to do this in python?
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How is IR spectroscopy used to determine the composition of asteroids?
I am trying to understand how spectrometers or spectroscopy can be used to calculate the surface composition of asteroids for the purposes of asteroid mining.
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absorption line from the chromosphere
If I understand correctly, the H-alpha and Ca II K lines are absorption lines of the sun and allow to see the chromosphere. Following the Kirchhoff-Bunsen law, an absorption line is produced by a gas ...
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Determining line ratios in planetary nebula
I know that the line strength ratio tells us how hot the electron plasma in a nebula is, and also give information about the electron densities in the nebula. But how do you compute the line ratios? ...
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Where can I find a database of elemental spectra? [closed]
I know that spectroscopy can be used to analyze the light of stars to determine the elements causing their emissions in the visible spectrum, but this requires knowing the emission spectra of the ...
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What spectral feature was used to confirm that S0-2 is "single and available"? What is Brγ?
The Phys.org article Astronomers discover S0-2 star is single and ready for big Einstein test describes the results of a careful analysis of radial velocity measurements of the star S0-2, which orbits ...
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How does an Echelle spectrograph put such a long, high resolution spectrum into a square-ish format?
In order to obtain a very high resolution spectrum to resolve closely spaced lines, or to measure doppler shits, spectrographs are operated with very high dispersion.
But photographic plates and CCDs ...
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Need help understanding stellar spectroscopy data from ESO
The European Southern Observatory webpage has a web page that has tabular spectrogram data from A. J. Pickles, University of Hawaii. There are over 130 .dat files there. Each one represents a ...
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Stellar electromagnetic signatures
By using only the electromagnetic signature of a star, could a star be distinguished with reliable accuracy from any other star?
To elaborate a little, say we have a collection of about 200,000 stars. ...
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How are the ESPRESSO Echelle spectrograph's calibration "lines" produced?
The CBC News Technology and Science Q&A This ESPRESSO machine doesn't make coffee but scans the skies for habitable planets includes a nice description of ESPRESSO (Echelle SPectrograph for Rocky ...
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How does the ESPRESSO Echelle spectrograph fold the spectrum so nicely?
The CBC News Technology and Science Q&A This ESPRESSO machine doesn't make coffee but scans the skies for habitable planets includes a nice description of ESPRESSO (Echelle SPectrograph for Rocky ...
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Spectroscopy of Exoplanets [closed]
How is accurate spectral analysis of a planets atmosphere achieved, bearing in mind that its host star's resultant light emission is not a full spectrum?
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Source for Identification of Balmer Hydrogen Absorption Lines
I'm working on an assignment, where I have to classify stars using the raw data of the telescope. I'm now trying to calibrate the pixel to armstrong ratio, and for that I need to identify the ...
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