乌鲁木齐达坂城区地税局大力加强纳税服务规范
1,898 questions with no upvoted or accepted answers
17
votes
0
answers
472
views
What is the limiting abundances of elements at the end of the stelliferous era?
Is there any reputable published source on expected elemental abundances at the end of the era of stellar fusion? I am here interested in the contents of galaxies; much of intergalactic gas will be ...
14
votes
0
answers
247
views
Estimating the tangential and cross component of the galaxy's shear using Gnomonic projection
I would like to know how I can estimate the tangential and cross component of the galaxy's shear using Gnomonic projection
of the right ascension and declination the galaxies relate to the center of ...
- 5,713
13
votes
0
answers
586
views
How are the aberrations seen in early JWST images corrected?
I found this image on space.com and it can also be found in NASA's JWST blog. This is one step in the process of aligning the 18 mirrors on JWST. A single relatively-isolated star has been selected. ...
Rob♦
- 2,686
11
votes
0
answers
266
views
How well conserved is etendue in extreme gravitational lensing scenarios?
This excellent answer to Could dark matter exist in the Universe in the form of sufficiently dense objects? includes the following image and description:
Light from the background galaxy circles a ...
- 4,333
11
votes
0
answers
554
views
What are the analysis steps in taking raw data from Kepler to a planetary system determination
I wish to get a concise list of the analysis steps required to take raw light data from a Kepler data set of a star through the steps needed to get to an analytical determination of the existence of a ...
- 1
10
votes
0
answers
156
views
Spatial wind speed distribution on Mars using dune shapes?
As a fan of exometeorology (the study of atmospheres of other planets), I scanned through a whitepaper Measuring Mars Atmospheric Winds from Orbit which says
Measurements of Mars
atmospheric winds ...
- 5,713
10
votes
0
answers
328
views
Water vapour in space
This question is inspired by, but different from, What happens if an ice cube is left in space?
Mark's accepted answer says "…if you stick your ice cube out in the Oort Cloud, it'll grow: the mean ...
9
votes
0
answers
110
views
The presence of maars on the Moon
Wondering if there's any evidence to date of the existence of maar craters on the Moon? If not, how probable is it that the moon ever supported the necessary conditions for maars to form?
A report ...
- 2,169
9
votes
0
answers
435
views
Did simultaneous transits of Mercury and Venus actually last occur in 373,173 BC?
According to the Wikipedia article for Transit of Venus, the last time a transit of Mercury and a transit of Venus occurred at the same time was 22 September of 373,173 BC. This is a Featured Article ...
9
votes
0
answers
2k
views
How to calculate the temperature of an exoplanet?
I was given an exoplanet similar in size and distance to host star to our own earth. It's orbiting a star with luminosity six times our sun, the greenhouse coefficient 0.3, bond albedo 0.3.
I would ...
8
votes
0
answers
679
views
Black spot in Mars' sky
There is a sequence of three raw images by Mars Curiosity Rover taken during Sol 3066 (22/03/2022, roughly) that show the same features of Mars' landscape and sky. They are separated by 38 seconds' ...
8
votes
0
answers
144
views
How long would it take to first detect a new object in the night sky given its apparent magnitude?
If an object as bright as the star Polaris (Apparent Magnitude +1.8) showed up in the night sky, it would be detected almost instantly by stargazers. If an object as bright as Pluto (Apparent ...
- 16.8k
8
votes
0
answers
143
views
What effect do aircraft have on night-time visibility?
I have something of an interest in astronomy. I also have a 5" reflector telescope, plus of course binoculars. With the recent coronavirus emergency, a large number of commercial aircraft were ...
8
votes
0
answers
637
views
How do I calculate the Hill radius of a star in a binary system?
Is there an easy way to calculate the Hill radius of a star in a binary system at different orbital radii where both stars are of the same mass and in circular orbit around one another’s centre of ...
- 31k
8
votes
0
answers
251
views
Detecting a Rogue Planet from Earth
This is for a novel.
A rogue planet, is, by a one-in-a-zillion freak chance, on its way to collide with Earth. It has been drifting in interstellar space since its original formation (billions of ...
- 1,047