New research shows that when an asteroid slammed into the moon billions of years ago, it carved out a pair of grand canyons on the lunar far side.

That's good news for scientists and NASA, which is looking to land astronauts at the south pole on the near, Earth-facing side untouched by that impact and containing older rocks in original condition.

Using satellite trackers, scientists have discovered the whereabouts of young sea turtles during a key part of their lives.

"We've had massive data gaps about the early baby to toddler life stages of sea turtles," said Kate Mansfield, a marine scientist at the University of Central Florida. "This part of their long lives has been largely a mystery."

NASA's two stuck astronauts took their first spacewalk together Thursday, exiting the International Space Station almost eight months after moving in.

Commander Suni Williams and Butch Wilmore removed a broken antenna and wiped the station's exterior for evidence of any microbes that might still be alive after launching from Earth and escaping through vents.

Asteroid samples fetched by NASA hold not only the pristine building blocks for life but also the salty remains of an ancient water world, scientists reported Wednesday.

The findings provide the strongest evidence yet that asteroids may have planted the seeds of life on Earth and that these ingredients were mingling with water almost right from the start.

The winter solstice is Saturday, bringing the shortest day and longest night of the year to the Northern Hemisphere — ideal conditions for holiday lights and warm blankets.

For those who would rather have more sunlight, you can try to make your way to the Southern Hemisphere, where it is summer. Or be patient: Starting Sunday, days will get a little bit longer in the Northern Hemisphere every single day until late June.

The U.S. has updated a decades-old science and technology agreement with China to reflect their growing rivalry for technological dominance. The new agreement, signed Friday after many months of negotiations, has a narrower scope and additional safeguards to minimize the risk to national security.

The State Department said the agreement sustains intellectual property protections, establishes new guardrails to protect the safety and security of researchers and "advances U.S. interests through newly established and strengthened provisions on transparency and data reciprocity."

Scientists suspect the first complete specimen ever recorded of the world's rarest whale died from head injuries, an expert said Friday.

The first dissection of a spade-toothed whale, a type of beaked whale, was completed last week after a painstaking examination at a research center near the New Zealand city of Dunedin, the local people who led the scientific team, Te Rūnanga Ōtākou, said in a statement issued by the New Zealand Department of Conservation.

Distant, ancient galaxies are giving scientists more hints that a mysterious force called dark energy may not be what they thought.

Astronomers know that the universe is being pushed apart at an accelerating rate and they have puzzled for decades over what could possibly be speeding everything up. They theorize that a powerful, constant force is at play, one that fits nicely with the main mathematical model that describes how the universe behaves. But they can't see it and they don't know where it comes from, so they call it dark energy.

A small, bright meteor lit up skies over the northern Philippines early Thursday as it burned up entering the Earth's atmosphere, the European Space Agency and witnesses said.

A spacecraft carrying European and Japanese probes passed closer to Mercury than originally planned overnight after thruster problems delayed the mission to study the little-known, Sun-scorched planet.