Unanswered Questions
100 questions with no upvoted or accepted answers
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Are astronomers still using photomultiplier tubes for optical photometry?
In Time domain astronomy and fastest eclipsing binary ZTF J1539+5027 (+20 mag, 6.91 minutes) How to measure it's minimum brightness? I've written
A logarithmic magnitude scale might tend to show ...
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How to remove radial velocity effects of an exoplanet from the host star spectra?
I have a spectra of an M dwarf and I would like to remove the Doppler shift effects due to a known exoplanet, with known planetary parameters, from the whole spectra of the star. I have shifted/...
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What happens to the Fourier Transform of the Measured Spectrum?
What happens when you double the width of the entrance slit of a spectrograph, in turn letting in twice as much light, would there be an improvement in the Fourier transform of the measured spectral ...
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Line Flux Ratios in Active galaxies
Good day to everyone.
I wanted to know what is the importance of estimation of line flux ratios in active galaxies? What does it help in characterizing?
As in Lyman $\alpha /$Carbon IV, or Mg II$/$...
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157
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Apparent Magnitude / Apparent Brightness relationship help
I'm a high-school student that is currently working on a project that describes, using mathematical notation and explanation, how scientists can find the values of each of the properties of stars, ...
CommunityBot
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2
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Correction to inverse square law for cosmology
While reading about the discovery of quasars and the spectroscopic analysis of 3C 273 in this paper by Maarten Schmidt, I came across the following quote:
At these distances, corrections to ...
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Why can't I use automatic photometry on IRIS?
I'm trying to do photometry on my stacked images of the night sky, but when I use the program IRIS and try to do automatic photometry, it always says it's a wrong image number and in every example of ...
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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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Convert RGB pixel value of an image to limiting magnitude
I have taken photos at different exposures from different places of the Orion constellation. I wish to find the effect of skyglow on the limiting magnitude of stars in the Orion constellation. How can ...
2
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102
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Can all astronomical signals be considered Gaussian noise?
While studying the techniques astronomers use to mitigate radio frequency interference (RFI) I found it's often assumed that astronomical signals are (band-limited) Gaussian noise. Is this a ...
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cross-matched SDSS-WISE catalog
Please where can I find cross-matched SDSS and WISE dataset for a machine learning project?
(Galaxy-star-qso classification task)
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magnitude calculation if a blackbody's radius and temperature are provided
I know it is necessary to convolve its spectrum with the transmission curve of a filter.
Are there any online tools or codes available for calculating a BB's magnitude in any specific band (e.g., ...
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How do you convert from the Gaia photometric system to Johnson-Cousin?
I have Gaia photometry (G, G_bp, and G_rp) and need to convert it to the Johnson Cousin system. In the Data release 3 (DR3) documentation they provide tables of how to do this but I’m very confused by ...
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Obtaining Transit Spectrum for Celestial Bodies Using JWST NIRSPEC
I've recently been tasked with obtaining transit spectrum data for some fascinating celestial bodies, including Ceres, Enceladus, Ganymede, Io, and Titan. The goal is to compare their transit spectra ...
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Using Gaia Passbands with L_nu coordinates
I am trying to find the coordinates of my bundles of gas on the gaia ($G, G_{bp}-G_{rp}$) hr diagram. I have its spectrum in $\nu L_\nu$ coordinates. Thus far, my attempts have mainly been to ...
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