No alien signal, says SETI astronomer

A strong signal from a sunlike star sparked speculation this week that we might - at last - have heard from an alien civilization. Now astronomers say ... no.

Watch spacewalk live September 1

NASA TV will broadcast live coverage on Thursday of a 6.5-hour spacewalk by 2 astronauts aboard ISS. Coverage will start at 6:30 a.m. EDT (1030 UTC). The spacewalk will begin about 8 a.m. EDT (1200 UTC).

Your cosmic suntan

Lie on the beach, and your body is bombarded by light from our sun, and from beyond our galaxy.

Watch SpaceX Dragon depart ISS Friday

Live coverage Friday of cargo ship's departure from International Space Station. Begins at 5:45 a.m. EDT (9:45 UTC).

Strong earthquakes rock Italy overnight

Dozens reported killed, and over 150 missing, in the earthquakes that shook Italy in the early morning of August 24. Searches ongoing.

Today in science: Gene Roddenberry

Happy 95th birthday to writer and producer Gene Roddenberry, creator of Star Trek.

Watch spacewalk live August 19

Two ISS astronauts will perform a spacewalk on Friday. NASA TV's live coverage starts at 6:30 a.m. EDT (10:30 UTC) and lasts about eight hours.

How did humans first reach America?

A new study suggests that the first people to reach America travelled via the Pacific coast rather than through a corridor between two giant ice sheets.

Atmospheric scientists say ‘no chemtrails’

Is there a large-scale, secret program to spray chemicals into Earth's atmosphere, resulting in "chemtrails?" Leading atmospheric scientists just say no.

Physicists confirm a possible 5th force

“If true, it’s revolutionary,” said Jonathan Feng, professor of physics and astronomy at University of California, Irvine and lead author of the new study.

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