A planet outside the solar system was discovered using a new method based on Einstein's theory of relativity

A team of astronomers from Tel Aviv University and the Center for Astrophysics shared with Harvard University and the Smithsonian Institute (CfA) announced the discovery yesterday

A team of astronomers from Tel Aviv University and the Center for Astrophysics jointly with Harvard University and the Smithsonian Institute (CfA) announced the first discovery of a planet outside the solar system using a new method based on Einstein's theory of relativity. The new planet, Kepler-76b, is referred to by the team as "Einstein's planet"
For the past two years, Professor Zvi Maza and his PhD student Simhon Feigler from Tel Aviv University have been searching for planets using a new method. They probe the light intensity of tens of thousands of distant suns to find periodic changes caused by invisible planets orbiting them. The planets cause changes in the intensity of light by three effects:

The first effect stems from Einstein's theory of relativity and causes the distant sun, which appears as a star in the night sky, to direct part of its light towards the viewer as it moves towards us. As a result the intensity of the light rises and falls as the sun makes small movements caused by the star planet around it. The discovery of planets using this effect was proposed back in 2003 by Avi Leib and Scott Gowdy. Leib is the head of the Department of Astronomy at Harvard University who also serves as a Sackler Professor by special appointment at Tel Aviv University.

The second effect stems from the fact that the distant sun is stretched into an egg-like shape due to the tidal force exerted on it by the planet surrounding it. As a result, the same sun appears brighter when we observe it from the side, due to a larger surface area, and less bright when the "pointed" side is facing us.

The third effect comes from the light radiation of that sun reflected by its planet. Since the brightness changes are very small, the three effects can only be detected from observations made by telescopes in space. The team from Tel Aviv University, supported by an advanced grant from the European Research Council (ERC), analyzed the data of more than one hundred thousand stars observed by NASA's Kepler space telescope, and looked for the relativistic effect in combination with the two other effects .

When a candidate for a planet is discovered, an international collaboration begins with the team of Dr. Dave Latham (Dave Latham) from the CfA, which also includes Dr. Lars Buchhave, for spectroscopic observations from the ground, in order to verify the existence of the planet

On May 2012, 76, Feigler and Maza noticed the three effects in one of the stars observed by Kepler. Following this, observations were made by Dave Leitam and his team at the Observatory in Arizona, as well as by Lev Tal-Or, another PhD student from Tel Aviv, at the Observatory in Provence, France. The observations from both telescopes confirmed without a doubt the existence of the planet, now called Kepler-XNUMXb.

The team, which includes Feigler, Tal-Or, Maza, Leitam and Bohaev, announced the discovery last week in an article to be published in the scientific journal The Astrophysical Journal.
The planet Kepler-76b, which is in the constellation Cygnus at a distance of about two thousand light years from us, has twice the mass of Jupiter, and orbits very close to its sun, with a cycle time of one and a half days. Its proximity to the Sun apparently causes it to be locked by tidal forces, so that one side of the planet faces the Sun all the time. This side of the planet is heated by its solar radiation to a temperature of about two thousand degrees Celsius.

While carefully examining the star's brightness data, the research team discovered strong evidence that the heat absorbed by the planet's atmosphere was carried by a strong wind current to a distance of about 15,000 km. This phenomenon was previously observed only in the infrared range, by NASA's Spitzer Space Telescope. This is the first time such a wind stream has been observed in the visible light field on a planet outside the solar system. The study of such wind currents is very important for understanding the reaction of the planet's atmosphere to very high intensity radiation.

All the planets found so far with the help of the Kepler spacecraft data were discovered because their orbit creates an eclipse of the distant sun that they orbit. The special feature of the detection method developed by Feigler and Maza is that it is also possible to detect planets whose orbit does not create an eclipse. "The irony is that Kepler-76b's orbit actually creates a small eclipse that occurs on the rim of its sun," Feigler says. "This is why the system was initially classified as a double star. Only through the discovery of the three effects were we able to identify that it really is a planet."

"This is the first time that this aspect of Einstein's theory of relativity has been used for the purpose of discovering a planet," says Prof. Maza, who is also a member scientist of NASA's Kepler space program. "We've been looking for this elusive effect for over two years, and now we've actually found a planet with it! It's amazing that Leib and Gaudi predicted this more than a decade ago. Professor Shay Zucker from Tel Aviv University, a former PhD student of mine, drew my attention to this effect. At first I didn't think the effect was detectable, but later I was captivated by the idea. Fortunately, we received the support of the European Research Council for the purpose of carrying out the research, and we also collaborated with Dave Laitham who believed in the project and continued to make observations of wrong candidates that we forwarded to him at the beginning of the search. We finally discovered Kepler-76b! It's really a dream come true."
"This discovery proves the ability of the new detection method," says Feigler. "We hope to find many more planets using the same method. All of this is possible thanks to the high quality of data that NASA collects with the Kepler spacecraft for more than 150,000 distant suns."

The research was supported by: European Community's Seventh Framework Program (FP7/2007-2013) ERC advanced grant no. 291352 – BEAMING.
The observations in France were made possible thanks to the European association OPTICON, which enables the sharing of observation time in European telescopes between astronomers. OPTICON is supported by the European Community's Seventh Framework Program (FP7/2007-2013)