Research on 100% renewable energy systems is a relatively recent phenomenon. It was initiated in the mid-1970s, catalyzed by skyrocketing oil prices. Since the mid-2000s, it has quickly evolved into a ...

It's an evocative idea that has long bedeviled scientists: a huge and mysterious planet is lurking in the darkness at the edge of our solar system, evading all our efforts to spot it.

Using the Dark Energy Camera astronomers have found a packed stellar nursery of infant stars in the dark nebula in the 180-light-year-wide Circinus West molecular cloud.

The supposed interstellar fireball detected over the Pacific Ocean in 2014 probably came from within our solar system, according to new statistical modeling of the meteor and others similar to it.

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Called "2I/Borisov" (formerly "C/2019 Q4" or "gb00234"), the object appears to be following a path originating from outside the solar system. It's expected to pass near Mars in October.

Plans are already emerging for a cavalcade of observations as C/2019 Q4 continues its journey through our solar system. “It’s going to be around for a comparatively long time,” says Matthew ...

It’s thought to be about a quarter-mile long, and about 10 times longer than it is wide. That makes it unlike any asteroids seen in our Solar System, none of which are so elongated.