does it go on forever? i know we can't see light from far off stars because of interstellar medium, but if it didn't exist, would the night sky be completely lit up?
2007-04-18 12:34:59 · 6 answers · asked by Jay 2 in Science & Mathematics ➔ Astronomy & Space
let's take an example. let's say, disregarding interstellar medium, there are two people standing 1 light second (3x10^6km) apart, and one shines a concentrated beam of light, would the other person be able to see it immediately?
2007-04-18 21:16:43 · update #1
Some say the whole universe if nothing is in the way. No one knows for sure, but this is what some scientists suspect. Some believe that Extremely Low Frequencies (ELF) may travel thru time, space and interacting with gravity and all sorts of things. Some believe these ELFs are what keeps us living.
They can be disrupted by other waves somewhat. The Earth is at 7.89 Hz, which is an Extremely Low Frequency ELF Range. The US Navy uses this to communicate with their subs. HAARP project is studying them for communication, preventing droughts, weather modification to help crops, all sorts of things. The uses are endless. We know they can travel thru Earth. The bodies bio system works at such frequencies and bacteria signals are near these too. Brain waves also in these ranges including; ELF, Very Low Frequency VLF and even ULF or ultra-low frequencies. They are everywhere and all we know, we are them, they are us. They are part of what makes us alive, think and perhaps so much more.
In the Ultra-Low frequency ULF ranges we believe are Earthquake frequency detection capabilities. To learn more about these frequencies you may wish to search on Google, Yahoo or MSN.com the following:
2007-04-18 14:06:18 · answer #1 · answered by Joe 1 · 0⤊ 0⤋
Not as far as it used to since it retired...
Sorry, I hadda say that...
I wish I knew the answer for you. But I did just read in one of SWH's book The Univese in a Nutshell, something relevant.
He said if the universe didn't have a beginning, that is, if it existed forever, the entire sky in all directions would be light up. Further that the fact that we don't see light in "almost" all directions if proof in a way that the universe and time itdself probably had a beginning.
2007-04-18 19:48:40 · answer #2 · answered by Nash 6 · 0⤊ 0⤋
in a vacuum, any moving particle will travel forever.
in order for us to see light, we have to either look directly at the source or find something to reflect it.
you cannot see a flashlight beam from the side, unless the air is dusty. the same with starlight.
2007-04-18 19:43:49 · answer #3 · answered by spoonman 3 · 0⤊ 0⤋
Light can travel an infinite amount of space in a vacuum.
2007-04-18 20:59:25 · answer #4 · answered by Anonymous · 0⤊ 0⤋
it depends on the amount of light a certain objet is giving out... the more light something gives out the more visible it will be. But light actully goes on forever.
2007-04-18 19:39:43 · answer #5 · answered by Anonymous · 0⤊ 0⤋
You seem to be restating Olber's Paradox. He did not know either.
2007-04-18 19:46:04 · answer #6 · answered by Bomba 7 · 0⤊ 0⤋