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WASP-17b

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description WASP-17b Overview

WASP-17b is a giant exoplanet announced in 2009 by the Wide Angle Search for Planets consortium. It holds the distinction of being the first exoplanet confirmed to orbit in a retrograde direction, moving in the opposite direction of its host star's rotation. Classified as a hot Jupiter, it is also notable for its extremely low density and heavily inflated radius, making it one of the largest planets ever discovered. The planet orbits an F-type star and completes a full transit every 3.7 days.

help WASP-17b FAQ

Why is WASP-17b considered a unique exoplanet?

WASP-17b is famous for being the first exoplanet confirmed to orbit its host star in a retrograde direction, meaning it moves opposite to the star's rotation. This bizarre orbital behavior was announced by the WASP consortium in 2009.

How was WASP-17b's retrograde orbit discovered?

Astronomers detected the retrograde orbit using the Rossiter-McLaughlin effect during a planetary transit. By measuring how the planet distorted the star's spectral lines as it passed across the surface, they could determine the angle of its orbit.

What is the physical size of WASP-17b compared to Jupiter?

WASP-17b is categorized as a 'puffy' or 'hot Jupiter' and is remarkably large, having a radius up to twice that of Jupiter. Despite its massive size, it has an incredibly low density, making it one of the least dense planets ever discovered.

Does WASP-17b orbit a star similar to our Sun?

WASP-17b orbits a yellow-white main-sequence star located about 1,000 light-years away in the constellation Scorpius. The host star, WASP-17, is slightly hotter and more massive than our own Sun.

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