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How long would it take for a radio signal from alpha centauri to reach earth?
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MrGray Send message Joined: 17 Aug 05 Posts: 3170 Credit: 60,411 RAC: 0 |
How long would it take for a sound signal from Alpha Centauri to reach earth? If frequency is a variable please explain time differentials. What spectrum of sound frequencies does SETI search through? I will be trying to calculate this myself but someone may know off-hand. Thanks in advance. . "Be who you are and say what you feel, because those who mind don't matter and those who matter don't mind." - Dr. Seuss |
kinhull Send message Joined: 3 Oct 03 Posts: 1029 Credit: 636,475 RAC: 0 |
How long would it take for a sound signal from Alpha Centauri to reach earth? I think it's about 4 years (Because it's roughly 4 light years away from our sun?) Alpha Centauri Alpha Centauri is the closest star system to our own solar system at 4.37 light-years distant (about 41.5 trillion km, 25.8 trillion miles or 277,600 AU). Proxima Centauri, often regarded as part of the system, is 4.22 light-years distant. Join TeamACC Sometimes I think we are alone in the universe, and sometimes I think we are not. In either case the idea is quite staggering. |
Graeme Stretton Send message Joined: 2 Nov 01 Posts: 392 Credit: 349,012 RAC: 0 |
How long would it take for a sound signal from Alpha Centauri to reach earth? It would never reach earth. Sound requires a medium, air, water etc. to travel through. SETI is "listening" to electromagnetic radiation, or if you prefer, radio waves. Hope this helps. Qunpu' lo'taHmo' jIH yItamQo' |
MrGray Send message Joined: 17 Aug 05 Posts: 3170 Credit: 60,411 RAC: 0 |
Woops, Sorry for the terminology error. I knew what I meant, but said what I didn't mean, lol. Thanks Graeme. So let me Google the speed of radio signals... Ok. Thanks guys! . "Be who you are and say what you feel, because those who mind don't matter and those who matter don't mind." - Dr. Seuss |
Ally Ein Send message Joined: 18 Feb 07 Posts: 49 Credit: 397 RAC: 0 |
I think this thread needs expanding. So new question: How long would it take for a typical NASA rocket to reach Alpha Centuri? And: What's so great about alpha Centuri anyways? |
tullio Send message Joined: 9 Apr 04 Posts: 8797 Credit: 2,930,782 RAC: 1 |
I think this thread needs expanding. So new question: I think the nearest star is not Alpha Centauri but Proxima Centauri, about four and a half light years away. Could not be reached by a chemical rocket even in a thousand years but only by ion propelled systems with nobody aboard. Tullio |
Clyde C. Phillips, III Send message Joined: 2 Aug 00 Posts: 1851 Credit: 5,955,047 RAC: 0 |
Alpha Centauri is about 25,000,000,000,000 miles away. Sound at sea level travels about 760 miles per hour (under standard conditions). So it would take sound about 3,750,000 years to get there if standard air extended all the way to the star. I guess that would be absolutely impossible-maybe that would coalesce into a big globular cluster or something(?). If a NASA rocket were traveling at Earths escape velocity (about 25,000 mph which is about 40 percent or so more than nearby satellite velocity) it would take 1,000,000,000 hours or about 114,000 years to get there. |
MrGray Send message Joined: 17 Aug 05 Posts: 3170 Credit: 60,411 RAC: 0 |
Amazing how small we really are! "Be who you are and say what you feel, because those who mind don't matter and those who matter don't mind." - Dr. Seuss |
Misfit Send message Joined: 21 Jun 01 Posts: 21804 Credit: 2,815,091 RAC: 0 |
with nobody aboard. I'll start up a collEction. me@rescam.org |
XboxAdmin Send message Joined: 18 Dec 00 Posts: 4 Credit: 13,755 RAC: 0 |
I know this is off topic but i cant post in some forums. How do i create a little graphic that others have showing my stats? |
Walla Send message Joined: 14 May 06 Posts: 329 Credit: 177,013 RAC: 0 |
Radio waves travel as fast as light waves because they are light waves. Gamma rays, x-rays, microwaves and radio waves they are all light waves. |
MrGray Send message Joined: 17 Aug 05 Posts: 3170 Credit: 60,411 RAC: 0 |
Yep, Google was faster. :) . "Be who you are and say what you feel, because those who mind don't matter and those who matter don't mind." - Dr. Seuss |
MrGray Send message Joined: 17 Aug 05 Posts: 3170 Credit: 60,411 RAC: 0 |
I think this thread needs expanding. So new question: Proxima Centauri. Interesting. This data look correct too you guys? http://en.wikipedia.org/wiki/Proxima_Centauri "Be who you are and say what you feel, because those who mind don't matter and those who matter don't mind." - Dr. Seuss |
Graeme Stretton Send message Joined: 2 Nov 01 Posts: 392 Credit: 349,012 RAC: 0 |
I know this is off topic but i cant post in some forums. How do i create a little graphic that others have showing my stats? Go to Your account / Profile /Edit profile. Down near the bottom of the page is what you need. Hope this helps. |
Ally Ein Send message Joined: 18 Feb 07 Posts: 49 Credit: 397 RAC: 0 |
What's so great about Alpha Centuri? |
Akhenaton Send message Joined: 11 Apr 03 Posts: 83 Credit: 4,128 RAC: 0 |
What's so great about Alpha Centuri? Apart from the Sun, it's the closest star system to us. The whole system consists of three stars, Alpha, Beta and Proxima Centauri. If we ever developed technology to travel between stars, it would be the logical first place to visit. |
devildog Send message Joined: 31 Dec 05 Posts: 9 Credit: 13,309 RAC: 0 |
We must remember that radio frequecies traveling long distances will degrade as the time from the initial point of transmission to receiver increases. In space there are many obstacles that radio frequencies must pass through like interstellar gases, UV radiation from sun's and even asteroid fields that would hinder this transmission. |
MrGray Send message Joined: 17 Aug 05 Posts: 3170 Credit: 60,411 RAC: 0 |
True! And a bunch of other variables too I bet. "Be who you are and say what you feel, because those who mind don't matter and those who matter don't mind." - Dr. Seuss |
jason_gee Send message Joined: 24 Nov 06 Posts: 7489 Credit: 91,093,184 RAC: 0 |
True! How about radio signals sent through wormholes, Could easily be mistaken for a natural phenomenon. "Living by the wisdom of computer science doesn't sound so bad after all. And unlike most advice, it's backed up by proofs." -- Algorithms to live by: The computer science of human decisions. |
MrGray Send message Joined: 17 Aug 05 Posts: 3170 Credit: 60,411 RAC: 0 |
True! But, maybe there is some noticeable effect on things traversing through the holes. "Be who you are and say what you feel, because those who mind don't matter and those who matter don't mind." - Dr. Seuss |
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