Questions tagged [astrophysics]
Questions involving the physics of the universe, especially the nature of astronomical objects, energy fields, and/or regions, rather than their positions or motions in space.
71
questions
1
vote
1
answer
56
views
What exactly does $k\sigma$ mean in astrophysics and cosmology?
In statistics, $\sigma$ or $1\sigma$ is the standard deviation. For the normal distribution, approximately $68\%$ of the values lie within $1\sigma$ range, $95\%$ within $2\sigma$, and $99.7\%$ within ...
- 441
0
votes
1
answer
147
views
Someone explain how a naked singularity is possible
I was reading this wiki article about naked singularities, however I don't really understand the how a gravitational singularity can simply exist without an event horizon. Can someone explain/...
2
votes
2
answers
75
views
Mathematical modeling of the influence of components of the interstellar medium on the distortion of the wavefront of the observed object
Associated with: Flowchart of the pipeline of key processes for modeling wavefront distortion of astronomical objects: ground-based observation case
Let's imagine for a moment that we are outside the ...
- 853
1
vote
1
answer
40
views
Flowchart of the pipeline of key processes for modeling wavefront distortion of astronomical objects: ground-based observation case
Associated with: Mathematical modeling of the influence of components of the interstellar medium on the distortion of the wavefront of the observed object
Being inspired by this article, as well as ...
- 853
1
vote
0
answers
15
views
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)
0
votes
2
answers
139
views
Do all photons coming out of the Sun go out radially?
I am trying to understand why we can assume that all light rays from the Sun are in parallel.
- 171
2
votes
0
answers
83
views
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
2
votes
2
answers
60
views
Computing error bar for vertex of parabola-fit lightcurve
I have a long-term lightcurve for my source, to which I have used orthogonal distance regression to fit a quadratic model [expected flux]=a[year]²+b[year]+c.
Part of our data analysis includes finding ...
- 23
-2
votes
0
answers
50
views
What is correct frame of reference for centrifugal force on planet?
How to correctly compute centrifugal force on object laying on equator of rotating planet with no axial tilt? I think there are two possible answers. First is that if the planet rotates so that one ...
8
votes
1
answer
574
views
References about neutrinos getting clumped in "structures" in the future?
I was wondering whether (standard model) neutrinos could form clumped structures (like halos perhaps). The problem with this is that neutrinos have a very light mass, have a great speed and do not ...
- 1,017
2
votes
2
answers
109
views
python question-discrepancy between number of stars found
Ok, I get that this is a long question but it's ok if you don't know just thought I'd give this a try anyway. I get that it's a long shot. Basically I'm trying to replicate a methodology used in the ...
- 29
3
votes
0
answers
41
views
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
0
votes
0
answers
34
views
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. ...
2
votes
0
answers
100
views
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
2
votes
1
answer
42
views
How to estimate perturbations from other planets in Apsidal Precession
I am developing a fictional system which I want to calculate to as much detail as I can. Thus I have a question about astrophysics and astrophysical formulae.
I know that Apsidal Precession is ...
- 376