Astronomers find a planet through a never-before-used method
They used pulsation to confirm a long-period planet around a Kepler candidate world.
Astronomers find a planet through a never-before-used method | Astronomy.com
http://www.astronomy.com/news/2016/10/astronomers-find-a-planet-through-a-never-before-used-method
Astronomers find most exoplanets from indirect signals, noticing changes in the light of the planet’s host star instead of by seeing the planet itself.
But some stars’ light changes all on its own, making these methods tricky at best. KIC 7917485b is the first exoplanet identified around a main sequence
A-type star from its orbital motion, and the first found near an A -typestar’s habitable zone.
A-type stars are bigger and hotter than most stars in the Kepler catalog and tend to be noisy, changing brightness at regular intervals. This dimming and
brightening can be hard to untangle from, for instance, a planet transiting and dimming its light. As such, while there’s no reason for A-type stars not
to have planets, it’s been difficult for astronomers to identify them. So far, the few exoplanets found around A-type stars are either from direct imaging
(which can only, where the planets are very far from their star, or from transits where the planets are very close to the star, where the signal is strong.