With 10 times the mass of our planet, and spending only part of its orbit in the habitable zone, Kepler-725c is very ...

Simulations show that the stars’ tug could send Mercury, Venus or Mars crashing into Earth — or let Jupiter eject our world from the solar system.

Spacecraft that orbit around Earth do so in two types of orbits: circular and elliptical. In a circular orbit, the spacecraft is always at the same distance from the center of the Earth.

"And so it wasn't getting fast enough to reach escape velocity. And so it ended up in a big elliptical orbit around the Earth." Sponsor Message McDowell says it's hard to predict where exactly on ...