Moment of Wonder: Spinning Around Two Suns

An artist's impression of a stellar eclipse and planetary transit events on Kepler-1647. Credit: Lynette Cook

NASA has announced its discovery of the largest known planet that orbits two suns. These bodies are known as circumbinary planets, or “Tatooine planets,” after Luke Skywalker’s home world.

The planet Kepler-1647b — roughly the mass and radius of Jupiter — is 3,700 light-years away and an estimated 4.4 billion years old, about the same age as Earth. The stars it orbits are similar to our own sun, with one slightly larger and the other a little smaller.

A team led by astronomers from Goddard Space Flight Center in Greenbelt, Maryland, and San Diego State University (SDSU) in California identified the planet using NASA’s Kepler Space Telescope. The discovery was announced this week in San Diego at a meeting of the American Astronomical Society.

“(Finding) circumbinary planets is much harder than finding planets around single stars,” said SDSU astronomer William Welsh, one of the coauthors of the NASA study on the planet. “The transits are not regularly spaced in time and they can vary in duration and even depth.”






Moment of Wonder: The Shock Breakout of a Supernova

NASA has shared some amazing footage of Mars, Pluto and the moons of Saturn. But this may be its recent money shot.

The space agency’s planet-hunting Kepler Space Telescope has for the first time captured the flash of an exploding star’s shockwave using optical wavelength, or visible light. Astronomers call this brilliant flash a “shock breakout.” They only last about 20 minutes and are essentially the opening salvo of a dying star going supernova.

A team led by Peter Garnavich, an astrophysics professor at the University of Notre Dame, analyzed light captured by Kepler every 30 minutes over a three-year period from 500 distant galaxies to obtain the the photometric observations used to create this video animation.

“In order to see something that happens on timescales of minutes, like a shock breakout, you want to have a camera continuously monitoring the sky,” Garnavich says. “You don’t know when a supernova is going to go off, and Kepler’s vigilance allowed us to be a witness as the explosion began.”

Sit back and enjoy the light show.