"Chaotic planets" that possess wildly unpredictable orbits and climates likely circle distant stars, suggesting that some alien worlds that look habitable might actually be hostile to life for millions of years at a time, a new study reports.
The supermassive black hole is 40 million times as massive as the sun and powers a quasar that existed 700 million years after the Big Bang.
The asteroid zoomed by Earth at a perfectly safe distance of around 1.8 million miles (2.9 kilometers).
Images show surprise changes to the spacecraft as it interacted with the atmosphere.
