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I have heard that the only planets able to be seen outside the Solar system are Jovian-sized planets with the occasional detection of planets three times the Earth's size. But, as far as I know, we haven't seen any Earth-sized (due to the range of our telescopes?) extrasolar planets. When will we be able to detect them?

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3 Answers 3

up vote 12 down vote accepted

The smallest detected exoplanet (Kepler-37-b) is actually smaller in mass and size than Earth, so we already have a limited ability to detect these size exoplanets.

It is worth noting that there wasn't any new technology that allowed this advance, the paper linked to by NASA indicates that the same methods were used as they would usually use. Making it remarkable that they were even able to discover something this small.


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Maybe update this answer. There are now a number of confirmed Earth-sized planets and most of the small planetary candidates found by Kepler will be real planets. So the answer is indeed that we already can and have. What there isn't yet - is an Earth-like planet in an Earth-like orbit around a sun-like star. –  Rob Jeffries May 3 at 14:16

Perhaps after the launch of ESA's PLATO space observatory, currently slated to be launched in 2024.

Planetary Transits and Oscillations of stars (PLATO) is a planned European Space Agency space observatory that will use a group of photometers to discover and characterize rocky extrasolar planets of all sizes around red dwarf stars, yellow dwarf stars like our Sun, and subgiant stars where water can exist in liquid state. . . . The goal is to find planets like Earth, not just in terms of their size but in their potential for habitability.

See also Jeremy's answer to this question.

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We can find Earth like Extra-Solar Planets, but they just might be too close to their star, and therefore, life might not be in the planet. We are right now living in a "Goldilocks Planet". Goldilocks planets are in the habitable zone, where there is life, and H2O that is at the right temperature to be a flowing liquid.

Anyway, a planet such as Gliese 876 d, is WAY too close to the star it orbits, (Gliese 876) Which it is highly unlikely that life exists, considering it is 377'C (710.6'F)

If you want to see a full table of exoplanets, then go to


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You need to be much more detailed with your answers. The same goes for your others. –  HDE 226868 Oct 27 '14 at 22:51
Thanks HDE 226868, I will use this as a learning experience and I'll try doing that next time. –  Juka Oct 27 '14 at 22:56
No problem. By the way, I can see a good answer in here. Try talking more about why it would be hard to find planets this small. –  HDE 226868 Oct 27 '14 at 22:58
I'll try doing that :) –  Juka Oct 27 '14 at 23:00

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