Unanswered Questions

10
votes
1answer
145 views

How has the Earth's orbit changed over hundreds of millions or billion of years?

First, I know that modeling orbital mechanics of 8 planets is hard, but there are some theories out there, for example, Jupiter is thought to have moved in towards the sun then started moving away. ...
8
votes
0answers
189 views

Magnetic fields of peculiar HgMn A type stars

Do HgMn (peculiar A type) stars really possess global magnetic fields? See, for example, this paper by Hubrig et al. from 2012.
6
votes
0answers
93 views

Are stars NML Cygni, UY Scuti, VY Canis Majoris and VV Cephei near the ends of their lives?

Are the three stars mentioned in the title stars that are going to go supernova, or are they stars that are in mid-life, like our Sun, but just happen to be so much larger than our Sun?
6
votes
0answers
52 views

Could the James Webb Space Telescope detect biosignals on exoplanets?

The James Webb Space Telescope (JWST) which is slated to launch in 2018 will bring us a better view of exoplanets, but will it be sufficient to detect signs of life on at least some of those worlds? ...
6
votes
0answers
72 views

Can there be an object with planetary discriminant between Ceres and Neptune?

The planetary discriminant is a measure of how dominant a body is within its region of the solar system. For (true) planets, it is >10000 and for dwarf planets it is <1. See this answer for more ...
5
votes
0answers
56 views

Is it accurate to compare comets to clouds and rain?

I'm trying to avoid an opinion-based question, so before I outline the comparison I'm proposing, I will qualify the specific facts that yield this comparison. By focusing answers on the relative ...
5
votes
0answers
62 views

Does CIBER Experiment from Caltech suggest that there can be lots of stars which are not in any galaxy?

My question is about the implications of the observations recently made by the Cosmic Infrared Background Experiment, or CIBER, from Caltech. I've read at Caltech web site: "The total light ...
5
votes
2answers
140 views

Likelihood of a stable system with a dwarf planet's orbit inside that of a gas giant

I keep thinking of various planetary system configurations, and would like to know: What are the fundamental references based on Monte Carlo long-term simulation of planetary systems' evolution that ...
5
votes
0answers
37 views

Going from the second moments of an object to its ellipticities and half-light-radius

I am studying ellipticity distributions of galaxies and am having trouble moving from the second central moment matrix (covariance matrix) to properties for an object such as its half-light radius. I ...
5
votes
0answers
26 views

Any new info about solar flares hitting the Moon added by the LADEE mission?

This article from 2011 mentions simulations about the sputtering effect caused by a solar flare hitting the Moon: "We found that when this massive cloud of plasma strikes the moon, it acts like ...
5
votes
1answer
175 views

What is the bluest narrow band filter mounted on ground based telescopes?

If we want to check a QSO's lyman alpha narrow band image, could a ground based telescope do that? I mean under the circumstance that its lyman alpha shifts to 3300A.
4
votes
0answers
27 views

Were parts of the Universe deflating during Inflation?

I was reading about the history of the early universe in Carroll & Ostlie and specifically looking at Inflation, which, as I understand, occurred because our [observable] part of the universe ...
4
votes
0answers
66 views

Orbits in a binary star system

I know of three sets of stable orbits in a binary star system: orbiting closely around star A, orbiting closely around star B, or orbiting distantly around both stars (and their mutual center of ...
4
votes
1answer
82 views

How to calculate the moon phase

I need a way of to calculate the moon phase. Do you know resources for research the theory from behind this? I basically have searched in Google, but the results were not very satisfactory. Exists a ...
4
votes
4answers
144 views

Image sets for testing stacking algorithms?

I am looking for sets of astronomical images for testing different kinds of stacking algorithms. The idea is simple: if one has $N$ images of the same object, the signal-to-noise ratio of the ...

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