Unanswered Questions
84 questions with no upvoted or accepted answers
3
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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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2
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51
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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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76
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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 ...
- 61
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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 ...
- 1,386
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Solar system datasets for exoplanet analogs?
Are there data from the solar system available, that are about quantities we regularly investigate in exoplanet searches?
The only collection I know of comes from this paper: "A Catalog of ...
- 399
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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 ...
- 121
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What instruments do amateur astronomers use in their ground based telescopes in order to avoid atmospheric absorption/telluric contamination?
What instruments do amateur astronomers use in their ground based telescopes in order to avoid atmospheric absorption/telluric contamination? For example, when an astronomer observes a celestial body ...
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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 ...
2
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84
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How can I compute reasonable errors on my Gaussian fits to the observed strong optical lines of interest?
I'm fitting Gaussians to optical lines spanning from H-beta to Sulfur using Astropy's Gaussian (https://docs.astropy.org/en/latest/api/astropy.modeling.functional_models.Gaussian1D.html) model with a ...
- 156k
1
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22
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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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1
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Space telescope spectroscopic data for stellar classification using Wien's law
My goal is to make a simple project which consists of classifying stars by applying Wien's displacement law.
I need public spectroscopic data about different stars from a space telescope, so that I ...
- 30.7k
1
vote
0
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58
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How do nuJ(nu) units work?
I'm working with (Nublado) Cloudy, which is essentially a spectral modelling tool for stellar matter. Using the software, I model my own stellar object and obtain its continuum.
According to Hazy, ...
- 156k
1
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53
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Determining the rotation curve of a galaxy via given spectroscopic data
Here is the data analysis question from IOAA-2011,
1. Weighing a galaxy: The image 8.2 shows a photograph of the spiral
galaxy NGC 7083, which lies at a distance of 40 Mpc, and image 8.3 a
fragment of ...
2
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answers
125
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How does one estimate the mass of a galaxy using the Balmer break region?
I am currently reading the recent astrophysical paper "A population of red massive galaxies ~600Myr after the Big Bang'.
In the first paragraph/abstract it mentions, "It has been difficult ...
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1
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answers
70
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Which stars are elliptical galaxies constituted by?
I know that elliptical galaxies are old galaxies, with almost no star formation and an old stellar population. This can be seen by their dominantly red spectra in the optical. I am trying to get a ...
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