Unanswered Questions
349 questions with no upvoted or accepted answers
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Keyerror: 0 while using astropy SkyCoord
I am facing a problem while using SkyCoord from astropy library. The scenario is as below,
I have read the data from a fits file into a pandas dataframe.
I have applied several quality cuts to the ...
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Are magnetic vortices capable of providing magnetic lensing when observed away from the poles
Magnetic vortices-(ESA cluster mission from observations November 2018)(article, ESA, science & exploration: 'Magnetic Vortices explain mysterious auroral beads'. An observer during Saturn's ...
- 20k
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What is the large dim feature near the center of the first James Webb image (of SMACS 0723)?
I was intrigued by the large dim feature (highlighted below) in the center of the first James Webb image of SMACS 0723. Is anything known about it?
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If you could get up close to them, what nebulae would be the most visually impressive to your naked eye?
Pop cult sci-fi movies like to show nebulae as they appear in photographs, but to a live, real-time viewer: these dazzling, snazzy and amazing backdrops to spaceship flying in front of them in real-...
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Explanation for Planck 2018 temperature fluctuations strongest peaks
As it can be seen from Plank 2018 Cosmic Microwave Background temperature fluctuations data-
There are 3 sharp peaks at multipole expansions $\ell \approx 250, 550, 800 $. Also as multipole expansion ...
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How are plage regions related to the density of medium and velocity FeII ions?
During a literature review (abstract), I found that the intensity of FeII (298.5 nm) ions in the last solar minimum was higher than the two previous solar minima 21 & 22. The velocity of FeII ions ...
- 30.3k
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How much more mass would Mars need to currently have enough pressure for liquid water and oxygen?
My question is whether Mars just about failed to meet the threshold or missed it by a lot. It's been dry for 3 billion years. How much bigger would it have needed to be to buy it that extra time? Let'...
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What exactly would the resolution of an exoplanet hypothetically imaged by using the Sun as a gravitational lens be?
This video talks about how by sending a spacecraft to around 600 AU and beyond, we would could use the Sun as a gravitational lens and take clear detailed images of exoplanets light-years away.
What ...
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From what distance could the Sun's planetary nebula be seen entirely with free eye?
When collapsing to a white dwarf, a red giant Sun would emit a planetary nebula. How far from the Sun would that nebula stretch at most?
Also: At about what distance could you see the planetary nebula ...
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Is it possible to use something besides emulsion to directly record the image of a nighttime object using a telescope?
The following questions have got me thinking.
Is it possible to use Photolithography for telescope image sensor?
Fresnel lenses for a makeshift Galilei telescope?
Has anyone ever tried to make a ...
- 30.3k
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K-correction vs resizing photometric bands
Is there a difference between a K-correction (see Wiki https://en.wikipedia.org/wiki/K_correction) and simply "resizing" the bands, e.g. the 2-10 keV x-ray band, with the redshift? I've read ...
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How did Michelson measure the diameters of jupiter's moons using optical interferometry?
In Betelgeuse: How its Diameter was measured (Chant, C. A., Journal of the Royal Astronomical Society of Canada, Vol. 15, p.133, Bibliographic Code: 1921JRASC..15..133C) the author says:
The paper in ...
- 30.3k
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How is the roll of the Hubble telescope around its axis and the dispersive direction(s) of it's spectrometer(s) managed?
Reading Dupree et al. 2020 Spatially Resolved Ultraviolet Spectroscopy of the Great Dimming of Betelgeuse (also in arXiv and summarized in Phys.org's Hubble finds that Betelgeuse's mysterious dimming ...
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Longest time after an image was taken when a new solar system body was discovered from it?
This answer to If there's nothing special about Pluto, why was it discovered so early? says:
In fact, often objects are discovered to be in pictures from long ago, such as Orcus, discovered in 2004, ...
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Cosmology : Formula for the bias of galaxies
first I have posted originally on the physics stackexchange but I have not had answers about my question, so I try my luck on this specific forum (if forums leaders want to delete the original post on ...
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