2007-02-17 12:29:47 · 8 answers · asked by sunnyjay 3 in Science & Mathematics ➔ Astronomy & Space
Do all wireless signals travel at the same speed? And is that at the speed of light?
2007-02-17 12:43:42 · update #1
Would signals fade or deteriorate over time & distance?
2007-02-17 12:45:06 · update #2
A better way to look at this is in terms of a light year (about 5,879,000,000,000 mile per year) The nearest 25 stars are 4.2 light years to 11.7 light years. Since waves of light, radiation, radio, etc all travel at the speed of light the assumption can be that our signals have traveled through several star systems (solar systems). The problem is that we don't have or produce any signal that could probably reach these systems before it is too weak to be recognizable. Not to say that they couldn't be detected. In terms of exactly how far, depends on when you consider the first "powerful" radio broadcast to be. I would say the 50's is when we started broadcasting "powerful" enough signals to travel outside of our solar system. So 50 to 60 light years would be about the best estimate. Our solar system is about 150,000 light years across. so we haven't sent signals very far yet.
2007-02-17 12:54:32 · answer #1 · answered by Rick P 3 · 0⤊ 0⤋
Radio signals do decrease in strength. You can think of it as visible light, as they are both electromagnetic waves. Light from a lightbulb decreases in strength as it moves farther away. This is because, at twice the distance, the same amount of energy is spread over 4 times the area.
2007-02-17 13:36:58 · answer #2 · answered by lotrgreengrapes7926 2 · 0⤊ 0⤋
About 100 light years.
Not far in a galaxy,there probably are no radio receivers in that radius that could under stand the signal.
That is what SETI is up against.
2007-02-17 12:39:59 · answer #3 · answered by Billy Butthead 7 · 0⤊ 1⤋
About 110 light years away. According to the Nearby Stars Catalog there are about 4000 stars our non-random radio emmisions could have reached.
2007-02-17 12:50:24 · answer #4 · answered by Labsci 7 · 0⤊ 0⤋
Radio waves were first created by humans in 1896 (approx).
It's been 111 years, so the radio waves would be 111 light years away. This is around 1.05E18 meters.
2007-02-17 12:37:21 · answer #5 · answered by Anonymous · 0⤊ 1⤋
radio signal,s travel at the speed of light.......so if the first signal of minimum strength ....say was broadcast in maybe 1957.....then it would be 50 light year,s away!
2007-02-17 12:39:57 · answer #6 · answered by slipstream 7 · 0⤊ 2⤋
You take the year they were invented, and multiply it by the speed of light, which is approximately 186,000 mps
2007-02-17 12:38:08 · answer #7 · answered by Anonymous · 0⤊ 0⤋
Those waves will not be much far, because they progressively lose strength and eventually die out.
2007-02-17 12:43:21 · answer #8 · answered by Yako 2 · 0⤊ 1⤋