Unanswered Questions
349 questions with no upvoted or accepted answers
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How does one determine the cardinal direction in which analemma was photographed?
Given an analemma, I am confused by how to obtain any useful information from it. Initially I thought you can at least determine the latitude of photographes, but this is clearly not the case, as it's ...
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How hard or soft is the Hubble's "science floor" due to atmospheric torque? Do some kinds of observations have lower floors than others?
After 04:58 in Scott Manley's How Failed Gyros Are Making Hubble's Life Harder:
And while the telescope is floating in space, it is still subject to small forces which can adjust its orientation. ...
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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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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 ...
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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 ...
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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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Declinations from stars apparent motion w/o plate solving
I am trying to program the calculation of the declination of the stars, based on their apparent movement through a series of astrophotographs, purely algebraically, without using a solver based on the ...
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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 ...
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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
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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?...
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How did Herschel determine the diameter of Mars?
The book The Planet Mars: A History of Observation and Discovery by William Sheehan states that
Herschel calculated the diameter of Mars to be 0.55 times that of the Earth, and he found its figure to ...
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Looking straight through the Milky Way Galaxy with the Gedanken Space Telescope from radio to 100 keV, what would the opacity vs wavelength look like?
Imagine that the "Large Gedanken Cryogenic Space Telescope" has been commissioned and aligned and is ready for its first test. It is equipped with a closed-cycle helium refrigerator to ...
- 30.3k
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Has anyone attributed a specific Baily's bead to a specific feature on the Moon? If so, when was this first done?
From Wikipedia's Baily's beads:
Lunar topography has considerable relief because of the presence of mountains, craters, valleys and other topographical features. The irregularities of the lunar limb ...
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What are the technologies needed to make deep space LIDAR competitive with RADAR? Any plans for tests, prototypes or "pathfinder" systems?
ProfRob's answer to Would it be practical to map out the Kuiper Belt and Oort Cloud via Radar? gives us a "sobriety check" on the idea. Citing an example of a 1 million watt transmitter at ...
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Tolerances given for Galactic Directions in answer to 'How fast are we moving relative to the CMB?'
Question: Tolerances given for Galactic Directions, in answer to 'How fast are we moving relative to the CMB?'
Where:
$$ℓ = 264.021º ± 0.011º$$
$$𝑏 = 48.253º ± 0.005º$$
I can find these values on ...
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