Questions regarding electromagnetic radiation in the visible spectrum.

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3
votes
3answers
426 views

How does gravity interact with a photon?

If photon is mass-less and gravity can interact only with matter, then how does gravity alter the trajectory of light?
14
votes
4answers
3k views

Is the light we see from stars extremely old?

Our nearest star Proxima Centauri is 4.243 light years away from Earth. Does that mean we are seeing light that is 4.243 years old everyday?
19
votes
3answers
1k views

Why can't light escape from a black hole?

I've heard that light can't escape from a black hole. Can it? If not, why?
18
votes
8answers
6k views

Why can't we see distant galaxies with the naked eye?

If light keeps travelling in a straight line, why can't we see distant galaxies with the naked eye? Surely if you stared long enough, the light from them would eventually hit your eye? I apologize if ...
16
votes
5answers
3k views

By putting a mirror in space, would we be able to see into the past?

I only ask this because of how fast light travels. The question remains in the title. Why, or why not, would this work?
13
votes
4answers
608 views

What is Gravitational Lensing?

What is the effect known as gravitational lensing? How does it work? What objects would be able to cause this effect?
2
votes
1answer
85 views

What is the ratio of cosmic microwave background radiation to normal radiation?

I would like to know the ratio of cosmic microwave background radiation to normal radiation in the universe. I am considering cosmic microwave background radiation to include the microwave, and any ...
9
votes
5answers
4k views

What would the effects be on Earth if Jupiter was turned into a star?

In Clarke's book 2010, the monolith and its brethren turned Jupiter into the small star nicknamed Lucifer. Ignoring the reality that we won't have any magical ...
6
votes
3answers
321 views

How does light affect the universe?

When light is emitted by for example a star, that star loses energy - which causes it to reduce its gravity. Then that energy begins a journey for potentially billions of years, until it reaches some ...
2
votes
2answers
255 views

Is it dark inside a black hole?

Assuming you could be standing inside a black hole, would it be light or dark around you?
0
votes
1answer
15 views

Why weren't the Hubble light-echo images of V838 Monoerotis supplemented by ground telescopes?

Drawing from this answer The V838 Monocerotis expansion (not a supernova) and the observation of the subsequent "spectacular" light echo was quite a notable event! From Nature 422, 405-408 (27 ...
0
votes
2answers
48 views

V838 Monocerotis “light-echo” images morphed into nice video, but why so few original images?

This NYTimes video shows what I think is a series of real Hubble images which have been "morphed" artistically to appear to be continuously expanding. (also see The V838 Monocerotis Star Still Has ...
0
votes
1answer
311 views

Is it possible that we see our solar system as a star?

A few days ago I just read here that our galaxies (one of which we are part of) move or expand faster than light, And read here that light we see from stars is extremely old, maybe more than several ...