Last week heralded as largest known asteroid to pass Earth until 2027. Swept within 1.3 times the moon's distance on October 31. Now thought to be a comet!
A black hole may flare when its corona - a mysterious source of highly energetic particles - launches away from the hole at close to 20 percent of light speed.
On Sunday, the craft that explored Pluto successfully executed the 2nd of 4 maneuvers designed to aim it toward a small Kuiper Belt object called 2014 MU69.
Evidence that Earth was hit by two solar storms - 10 times larger than those observed recently - 1,000 years ago. If they occurred today, they'd have devastating effects on power supplies, satellites and communications.
SOHO - Solar and Heliospheric Observatory - is the greatest comet-discoverer of all time. It has found 3,000 comets ... but our sun has destroyed nearly all of them.