0
The exact number is not known. But it does seem that most stars have at least one planet, and probably several planets, at least on average. Not even the number of stars in the immediate neighborhood can be known for sure, since red dwarves are quite hard to detect.
Here is an estimate. The Wikipedia article on "List of nearest stars" lists 56 hydrogen-fusing stars at a distance up to 5 parsec, or 16.3 light-years. Assuming the density of stars is more or less constant at distance up to 100 light-years, that would mean that for a volume 231 times larger (up to 100 light-years), there would be about 12,930 stars. Assuming that each of them has 1-10 planets on average, and doing some rounding, that would mean there are between 13,000 and 130,000 planets at that distance. Please note that despite the fairly large range, there is still a lot of guesswork involved.
Wiki User
∙ 10y ago
Add your answer:
Earn +20 pts
How many planets Earth signal reaches?
All of them in our solar system, plus all others within a distance of about 100 to 120 light years from us.
Are all stars the same distance from the earth?
No two planets within our solar system have the same exact size. However, Earth and Venus are quite close - their diameters differ by only 652km.
What planet is 1000 light years away?
Because planets are rather small on astronomical scales - or at least, when compared to stars, and not luminous like stars, it is very hard to see them at great distances. NASA's Kepler spacecraft, which was launched to detect planets within habitable zones of stars, detected in 2011 a couple planets orbiting a star roughly 1000 light years distance. The planets, designated Kepler 20e and 20f, are part of an unusual solar system, and are roughly Earth-sized and 'rocky' but orbiting their host star within the distance of Mercury to our Sun, which would make them too hot for life.
What is the distance between planet earth and planet Kepler?
There is no planet Kepler. Designations such as Kepler-69c are given to planets discovered by the Kepler spacecraft. This spacecraft has discovered planets ranging from 100 to 7,000 light years away.
As we can see planets galaxies light years in the past with telescopes couldn't we send spacecraft far enough into space to record to see Earth light years in the past to settle creation argument?
That would involve building spacecraft to exceed the speed of light, which at the moment is impossible.
When should you use light years?
Light years are used to measure distance from Earth to distant stars and planets.
How many planets Earth signal reaches?
All of them in our solar system, plus all others within a distance of about 100 to 120 light years from us.
Are Kepler and earth in the same galaxy?
Yes. Anything within 25,000 light years is within our Galaxy.
Is there any planets just like earth?
that remains to be seen. although the chances are slim, there might be an earth-like planet millions of light-years away!
Are all stars the same distance from the earth?
No two planets within our solar system have the same exact size. However, Earth and Venus are quite close - their diameters differ by only 652km.
How many light years to the Saturn?
The distance from the Earth to Saturn varies - depending on whether both planets are on the same or opposite sides of the sun. At their nearest the distance is approx 0.000127 light years.
How many years does starlight travel?
It depends on the distance of the star to Earth. The distance to the star in light years is the number of years the light took to get here. Most of the stars we see at night are within a few hundred light years of Earth. The closest star other than the sun is about 4.2 light years away.
Do All stars in a constellation have to be within a light year?
No. No star other than the sun is within a light year of Earth. Most of the stars in constellations are dozens to hundreds of light years away.
Did the NASA ever sent a robot out space to find another sun and earth billions of lightyears away?
No. We cannot detect stars and planets at such distances. The Kepler telescope searches for planets in a region of space that is generally within an few hundred light years of us. The telescope itself orbits the sun and remains much closer to us than a light year.
How long are the planets years?
Uranuses year is 84.3 Earth years
What planet is 1000 light years away?
Because planets are rather small on astronomical scales - or at least, when compared to stars, and not luminous like stars, it is very hard to see them at great distances. NASA's Kepler spacecraft, which was launched to detect planets within habitable zones of stars, detected in 2011 a couple planets orbiting a star roughly 1000 light years distance. The planets, designated Kepler 20e and 20f, are part of an unusual solar system, and are roughly Earth-sized and 'rocky' but orbiting their host star within the distance of Mercury to our Sun, which would make them too hot for life.
How many light years away is the closest planet to earth?
Every planet in the Solar System is closer than one light year to the Earth. In fact, when you travel at the speed of light on January first departing from our own star (the sun) it is still January first when you pass Pluto...
