Planets outside the Solar System: EXOPLANETS

In the last couple of years, a number of planets have been discovered around nearby stars. Planets can be discovered by different means:

• Direct detection: the planet is actually seen.

• Indirect detection: the planet's existence is inferred from the observed motion of its parent star by observing the doppler shift of spectral lines or by seeing the star wobble around a center of mass.

The second method of discovery is much easier than the first - though both are TOUGH.

Different techniques for detection have produced discoveries at different wavelengths:

The planetary system around the pulsar PSR 1257+12, the first exoplanets to be discovered. Yes, that's right. The first planets outside the solar system were discovered first by radio astronomers. Who would have guessed?!

Recent optical/infrared discoveries.

External links to interesting pages

• The Marcy and Butler home page of latest results.

• The ExtraSolar Planets Encyclopaedia keeps track of the latest result. You can also read this in French, if you'd like.

• Extrasolar Visions.

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