Tagged Questions
6
votes
1answer
94 views
Distribution of star colours in a galaxy
I'm trying to randomly generate a representation of a galaxy.
I have some Idea on the spatial distribution of stars within a galaxy, and I can find plenty of material on the colour of stars, but ...
4
votes
1answer
121 views
Very large absorption lines in stellar spectrum
I was puzzled by the wide absorption lines in a stellar spectrum I found. The following is what I expect absorption lines to look like - thin, crisp lines:
However, I found this stellar spectrum, ...
0
votes
2answers
258 views
EM waves: How do they travel for billions of km without damping
If a star is 1 billion light years away, it means that the light we see from the star is emmitted billions of years ago.
How does this light not undergo a frequency change or get damped inspite of ...
5
votes
3answers
287 views
How many percent of the visible light reaching the Earth are from other stars than the Sun?
How many percent of the whole visible light reaching the Earth are from other stars than the Sun?
Is it maybe 0,5 - 1% or is my guess already too much?
I am interested mainly in visible light, but ...
0
votes
1answer
114 views
Does diffraction contribute to the Black Drop effect?
Two reasons are given to explain the black drop effect here, but I think I came up with a third.
Consider a two-dimensional cross section of the situation just after second contact and just before ...
3
votes
1answer
32 views
Assuming an observer is 50 light years away, in the plane of the solar system and observing earth, what is the light flux of earth he would see?
As in, from what the planet emits and re-radiates out into space (this is going to be important if we are to image any Earth-like planet)
12
votes
2answers
302 views
What if our Sun were located in the middle of a globular cluster?
Say you took our current solar system and relocated it deep in the heart of a globular cluster such as Omega Centauri. What would the night sky look like? Would the starshine of nearby stars be enough ...
15
votes
5answers
772 views
What do the colors in false color images represent?
Every kid who first looks into a telescope is shocked to see that everything's black and white. The pretty colors, like those in this picture of the Sleeping Beauty Galaxy (M64), are missing:
The ...
7
votes
2answers
503 views
What does the sky look like to human eyes from orbit?
There are numerous pictures, obviously, of the blackness of space from the shuttle, the space station, and even the moon. But they all suffer from being from the perspective of a camera, which is not ...
3
votes
1answer
206 views
Lunar twilight and sixth magnitude stars
Summary: when the Moon is x degrees below the horizon, it interferes
with stargazing the same as astronomical twilight would. What is x (as a
function of the Moon's phase)?
We define civil, ...
