寻找行星的新方法

Detecting alien worlds presents a significant challenge since they are small, faint（模糊的）, and close to their stars. The two most prolific¹（丰富的） techniques for finding exoplanets are radial velocity² (looking for wobbling摇晃的 stars) and transits⁴ (looking for dimming stars). A team at Tel Aviv University and the Harvard-Smithsonian Center for Astrophysics (CfA) has just discovered an exoplanet using a new method that relies on Einstein's special theory of relativity. "We are looking for very subtle effects. We needed high quality measurements of stellar brightnesses, accurate to a few parts per million," said team member David Latham of the CfA.

 

"This was only possible because of the exquisite⁵（精致的，细腻的） data NASA is collecting with the Kepler spacecraft," added lead author Simchon Faigler of Tel Aviv University, Israel.

 

Although Kepler was designed to find transiting⁶ planets, this planet was not identified using the transit³ method. Instead, it was discovered using a technique first proposed by Avi Loeb of the CfA and his colleague Scott Gaudi (now at Ohio State University) in 2003. (Coincidentally, they developed their theory while visiting the Institute for Advanced Study in Princeton, where Einstein once worked.)

 

The new method looks for three small effects that occur simultaneously⁷ as a planet orbits the star. Einstein's "beaming" effect causes the star to brighten as it moves toward us, tugged⁸ by the planet, and dim as it moves away. The brightening results from photons "piling up" in energy, as well as light getting focused in the direction of the star's motion due to relativistic effects.

 

"This is the first time that this aspect of Einstein's theory of relativity has been used to discover a planet," said co-author Tsevi Mazeh of Tel Aviv University.

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