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 is DESI's spatial resolution?
I'm using data from the Dark Energy Spectroscopic Instrument (DESI), and I need to check if its beam coincides with coordinates I've collected for objects in GALEX.
From the Fermilab conference ...
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Degrade resolution of theoretical spectrum before fitting
I want to fit a theoretical spectrum on a finely spaced wavelength
grid to an observed stellar spectrum at coarser resolution. I understand
that I have to apply convolution to the theoretical spectrum ...
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Why does infrared pass through clouds of gas and dust with minimal extinction?
Why do we use Infrared to view through clouds of gas and dust in space? I understand that it is because it can pass through without being absorbed, but why is this? My thinking is that it is because ...
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Why MIT's Benjamin Rackham says "nearby ultracool dwarf SPECULOOS-3" would look "purplish-red, spotted, and flaring" from an airless orbiting planet?
May 15, 2024 MIT News article Newly discovered Earth-sized planet may lack an atmosphere includes the following:
“We can say from our spectra and other observations that the star has a temperature of ...
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Rectification of M-type spectra
I would appreciate references and/or tips on estimating the continuum
in the spectra of M dwarf stars. The ultimate aim is to obtain radial
velocities from sequences of spectra by comparing to a ...
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How to identify Hydrogen lines of slitless spectrograph of Type A9 star
Hi I am analysing slitless spectrograph of type A9 star Canopus. Here is as sample of the spectrograph.
I basically did a simple summing up of the columns and added the data (as a simple spectrum co- ...
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Where in a star are the spectral absorption lines formed?
This question was inspired by a recent Cool Worlds video "The Star That Shouldn't Exist", in which one of the speculative solutions to Przybylski’s Star's strange spectrum is aliens "...
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Why is the filter needed for low resolution GMOS spectroscopy?
I am considering writing a proposal for using the GMOS with the R150 grating. I want to measure the redshift of multiple systems from the strong lensing effect of some clusters, so the redshift range ...
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Does the expansion and contraction of a variable star affect the measured radial velocity?
I've measured the heliocentric radial velocity of Beta Cephei using the doppler shift of the helium lines, I corrected for earth's motion using the doppler shift of the oxygen in the atmosphere. I ...
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How to convert flux to flux density for a synthetic spectrum?
I have several model SEDs generated by the CLOUDY spectral synthesis code. The data is formatted with one wavelength column and one flux column. I wish to perform Hubble synthetic photometry on these ...
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Calculate change in spectral line intensity for a change in temperature
I am trying to do some simple modelling of spectral line emission. I am starting with some ALMA observations of a protoplanetary disk, where the emission from a particular molecule at frequency 344GHz ...
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Why is the H-alpha line slightly shorter in wavelength (656.28 nm) in air than in vacuum (656.46 nm)? Shouldn't it be longer?
Perhaps this is a question better suited for Physics SE, but since the H-alpha line is so important in astronomy, I'm posting this here....
I would, naively, assume that wavelengths would be longer, ...
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What is a good resource for finding accurate apparent magnitudes stars in different filters?
I am unable to find this information online, does anyone know of a database, book, or website that contains all of the B-band, V-band, I-band etc.... apparent magnitudes for each star?
Thanks for any ...
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Determining Stellar Activity
I've been into exoplanets and the search for life for a few years now, but I'm still very much an amateur. The basics are fairly easy: habitable zone adjusted for planet/moon mass, no brown dwarves (...
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Formation of spacecraft instrumentation [closed]
List of spacecraft instruments are selected to meet a mission's science goals.
Let's take New Horizons as an example and study the composition of Pluto's atmosphere, the shape and geological ...
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