Two reasons.
(1) Such planets are very dim, from our point of view. Some of the planets in our own Solar System look roughly as bright as the brightest stars; now imagine them at least 100,000 times farther - that would make them 10 billion times dimmer, from our point of view.
(2) Such planets are very close to their star - once again, from our point of view, i.e., considering the angular distance.
Mainly because astronauts don't look for them. Astronomers do.
there is no life on extrasolarplanets
That doesn't make sense. There are stars, and there are planets. If you mean "planets around stars, other than the Sun", those are usually called "extrasolar planets" or "exoplanets".
Well, to explore space ofcourse. Astronauts go to space to find new planets or such. They observe what is happening.
mercury
Astronauts go to different planets etc and collect specimens and other things so that scientists can research and find out more about our solar system.
Astronauts who do their homework and learn what they're supposed to learn are rewarded with a flight into space.
Light from the stars they orbit makes it difficult to see them.
Its simple! They use telescopes instead!
Planets are considerably smaller than their parent stars, also they emit no light and are very close to the star. With all this combined, separating between the two with a telescope is very difficult.
light from the they orbit makes it difficult to locate extrasolar planets with telescope
light from the they orbit makes it difficult to locate extrasolar planets with telescope
Planets are considerably smaller than their parent stars, also they emit no light and are very close to the star. With all this combined, separating between the two with a telescope is very difficult.
Planets are considerably smaller than their parent stars, also they emit no light and are very close to the star. With all this combined, separating between the two with a telescope is very difficult.
I would suppose that the scientist with the super powered telescopes would discover planets before the astronauts would.
Extrasolar planets are planets found orbiting stars other then our own.
extra solar planets are not bright compared to the stars they orbit
Yes. So far nearly 2,000 extrasolar planets have been discovered.
extrasolar planers are not bright compared to the stars they orbit For approximately the same reason that it's difficult to spot a mosquito circling a street light that is 5 miles away, with a telescope.