Or is it instantaneous? Also are what we see in the sky that we term stars all like the sun or are some planets and if so where is the light coming from and how is it relfected to us. does the earth glow like a star from another planets perspective?
2006-09-04 12:51:17 · 21 answers · asked by Rock Skull 2 in Science & Mathematics ➔ Astronomy & Space
we will not know the star is gone for seventy years.
2006-09-04 12:53:01 · answer #1 · answered by warm soapy water 5 · 2⤊ 0⤋
Hi. A star 70 light years away could go out or explode and we would not see it for 70 years. The planets which are visible reflect light from the sun. If you look at a crescent moon, sometimes the dark portion of the moon is slightly visible. This is Earth shine reflected on the moon's surface then back to your eye, so yes - the Earth can shine like a star from the point of view of other planets in the solar system.
2006-09-04 13:02:53 · answer #2 · answered by Cirric 7 · 0⤊ 0⤋
Yes. The last light from the star would still have to travel the 70 light years. Another example closer to home is it takes light 8 minutes to reach the earth from the sun. If the sun were to turn off, like a gigantic light bulb, we wouldn't know about it for 8 minutes.
2006-09-04 15:03:49 · answer #3 · answered by Anonymous · 0⤊ 0⤋
It will still be visible for the next 70 years.
Most of what you see in the sky at night are stars, somewhat like our sun. Of course, there are various types such as white dwarfs, red giants, etc. If you notice something that looks like a star but does not twinkle and is somewhat red, you may safely assume it's a planet in our solar system. It gets its light from reflecting light form the sun. And yes, Earth would look like one of these planets if viewed from a very far distance (not from the moon; that's nearby).
2006-09-04 12:53:59 · answer #4 · answered by flandargo 5 · 0⤊ 0⤋
Yes, though I'm sure that the fact that it died can be detected despite the light we're receiving.
The gravitation of heavy-enough stars affect other objects around them, even other stars in some cases. When the star itself dies, even if it's light-years from us, and although it would take a certain amount of time for the final light that star emits to reach our eyes, the orbits of the matter which may have gotten caught within the star's graviational pull would be altered or even destroyed themselves.
I do suppose that this change in orbit which would otherwise be detectable, could not also be detectable due to the limited speed at which light travels, but it is something to think about. If in some way what we could notice about the orbits of planets and other objects which used to rotate about a star before it died could be detected outside our dependency upon the speed of light, we'd know precisely when a star has died despite the fact that we'd be observing the radiation it had emitted mere instants before it died in the first place.
Sorry for being so wordy, but I hope you understand the gist of what I was saying.
But in all essence in directly answering your question: Yes, because of the time it would take light to reach us is directly proportional to the distance at which the source emitting the light is located, it would take the 70 years for that source's radiation to reach our eyes.
2006-09-04 13:06:08 · answer #5 · answered by Angela 3 · 0⤊ 0⤋
It will take 70 yrs. No, the earth will not glow that way, stars are all like the sun, with their own planets to light up.
2006-09-04 12:58:54 · answer #6 · answered by Jilly B 2 · 0⤊ 0⤋
yeah, it takes 70 years to find out (i.e. last particles emmited by a dying star will reach us in 70 years).
No, the earth doesn't glow like a star because the earth doesn't emit light. It looks like a planet, not like a star. It reflects light. So if you have a good telescop, you see that it is a planet. If you have your naked eyes and nothing more, then it looks like a star. If you look at Mars from the Earth this is what you see. Mars is a planet not a star.
2006-09-04 12:57:23 · answer #7 · answered by Snowflake 7 · 0⤊ 1⤋
If you look at a star that is 70 light years away, what you are really seing is the star as it was 70 years ago. The light that is reaching your eye today started out on its journey 70 years ago. If the star suddenly dies and goes out, the light already in transit will continue along and continue to reach us here on earth for the next 70 years, at which time it will suddenly wink out.
2006-09-04 12:56:00 · answer #8 · answered by Kokopelli 7 · 1⤊ 0⤋
yes...it takes 70 years for the light to travel,
planets will reflect light to a certain extent....depending on there distance from a star or other light source.
yes the earth will glow because it reflects the sun's light, but once again ...the visibility of the earth will depend on the distance of the planet we are looking at earth from.
2006-09-04 13:41:52 · answer #9 · answered by banandmajid 1 · 0⤊ 0⤋
Precisely right ... we wouldn't know it was dead for 70 years. The light we see is from stars and some of the planets in our own solar system, and the occasional spacecraft decelerating towards us (those fusion drives can be easily confused with stars). See, planets are so dim that they are effectively "dark" outside the immediate solar system. The planets that have been detected have been noted through the wobble their mass causes in their parent star's motions.
2006-09-04 12:53:37 · answer #10 · answered by Grendle 6 · 0⤊ 0⤋
70 years. A light year is a unit of distance. It is measured as the distance lite travels in one year. So it would take a year for every one of those lightyears to be covered by the image of the star.
2006-09-04 12:59:44 · answer #11 · answered by haha10488 3 · 0⤊ 0⤋