Unanswered Questions
172 questions with no upvoted or accepted answers
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Answer this or don't downvote
Otherwise you'll be showing your complete ignorance in the matter and contempt for the truth.
If the scale factor as a function of time represents or is equal to the average distance between the ...
2
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0
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69
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Using prospector for jwst data
I am working with JWST data. I want to estimate the redshift of the sources I have identified with SEXtractor with the help of prospector. Can somebody guide me in this?
- 51
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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)
2
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How to convert .exp files from NRAO VLA Archive to .fits format
I recently downloaded some observational data files from the NRAO VLA Archive, and they have the extension .exp. These are old observations. I need to convert these files to .fits format for further ...
- 30.7k
2
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84
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Would we know if the universe was rotating?
I was wondering what we would observe if the universe had a small rotation. My conclusion was that galaxies on the equatorial plane of the universe would be slightly more redshifted than galaxies than ...
- 373
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 ...
- 30.7k
1
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0
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43
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Tiling the sky with astropy-healpix
I have a bunch of files containing sources with galactic l and b values. What I want is to redistribute the sources such that each new file contain sources that fall within 15 degrees of a central l,b ...
- 30.7k
1
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1
answer
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Calculating field rotation between two times
I have the formulae to calculate the rate of field rotation at any given time, and using a python script with Skyfield I can generate a a value incrementing every 10th of a second based on the live ...
CommunityBot
- 1
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Project Analog Hypothetical Planet
For my story Project Analog, I was wondering if a hypothetical planet (Let's call it Suria). It has the same size and conditions as Earth with the same axis, tilt, and rotation, as well as one moon. ...
CommunityBot
- 1
2
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0
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101
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What would the Big Crunch theoretically look/feel like?
In the Big Crunch theory, the expansion of the universe reverses, resulting in all matter contracting into a single point. Imagine you are alive at the time of this event. What would the sky look like?...
- 29
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64
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2
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Local anisotropies in the expansion of the universe and tidal forces...?
In the context of the large-scale structure of the universe, there can be local anisotropies (https://www.aanda.org/articles/aa/full_html/2021/05/aa40296-21/aa40296-21.html).
I understand from this ...
- 1,017
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25
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Deriving Faber-Jackson Relation from Milgrom's Law
I am reading Famaey & McGaugh 2011, a review paper on Modified Newtonian Dynamics. My question concerns bullet 3 in Sec 5.2, where the authors try to explain how Faber-Jackson Relation can be ...
- 779
1
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0
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121
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Determining Time Based on Arc Seconds
So our arc day starts at 20°41'32 which is midnight (0:00) and ends 24 hours later at 21°42'42. According to my calculations it traveled 0 degrees, 59 minutes, and 30 seconds or 3570 arc seconds in 24 ...
- 2,339
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Python Lightkurve Module -- How to combine different TESS sectors into one graph
I'm building a pipeline to look at several thousand eclipsing binary systems for my master's thesis, and I've run into an issue I am having a hard time fixing. I'm using the Python module Lightkurve.
...
