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Kepler finds 10 Earth-like exoplanets

NASA’s Kepler space telescope has identified 219 new exoplanet candidates, 10 of which are near-Earth size and in the habitable zone of their star.

Space gardening

Future space outpost dwellers will need to grow plants for food and to recycle air and water. Here’s what scientists are learning about space farming from plants grown on the ISS.

Video: Watching solstices and equinoxes from space

See how sunlight falls on Earth’s surface during the solstices and equinoxes, and get a better understanding of why Earth’s tilt causes the seasons.

Elon Musk’s Mars manifesto

What if the cost of going to Mars as a colonist were less than US $200,000, or about the median cost of a house in the U.S.? Would you go? Elon Musk thinks many would.

Today in science: Sally Ride in space

She was the 1st American woman in space, eventually flying on 2 shuttle missions. She played a key role in the investigation of the Challenger disaster. And she inspired people.

Does the North Star ever move?

It’s a symbol for constancy, but, if you took its picture, you’d find that the North Star makes its own little circle around the sky’s north pole every day.

Are asteroids hiding among the Taurids?

And, more to the point, are any asteroids that might be hidden in the Taurid meteor stream potentially hazardous to Earth?

10 space objects to see daytime

A rundown of the top 10 space objects you can see – under the right conditions – during the day.

Did our sun have a twin?

A new analysis suggests the likely answer is yes — though not an identical twin. And so did every other sunlike star.

Galaxies have aligned for 10 billion years

Most galaxies are randomly oriented in space, but the biggest ones often point toward their neighbors. A new study traces these alignments back into the early universe.

How much moon do we see?

One side of the moon always faces Earth. Even so, over time, it’s possible to see as much as 59% of the moon’s surface, due to lunar libration.

Amazing views of waltzing nearby stars

Astronomers used the Hubble Space Telescope to follow the 2 brown dwarfs in the Luhman 16AB system, as they move both across the sky and around each other.

Dwarf star bends light, confirms Einstein

Awesome observation! Astronomers used the Hubble Space Telescope to measure the mass of a nearby white dwarf, as it bent the light of a more distant star.

Wow! signal explained after 40 years?

New evidence suggests the well-known Wow! signal from 1977 – long thought by some to be a sign of extraterrestrial life – was in fact generated by a passing comet.

A planet hotter than most stars

Astronomers have discovered a Jupiter-like world hotter than most stars. The planet has a year only 1.5 days long and might have a tail like a comet.

How hard did it rain on Mars?

In a new study, geologists show there was rainfall on Mars in the past – and that it was heavy enough to carve out many of the features we see today on the planet’s surface.

What is the electromagnetic spectrum?

The electromagnetic spectrum describes all the wavelengths of light. From dark nebulae to exploding stars, it reveals an otherwise invisible universe.

Saturn’s moon may have tipped over

Scientists used Cassini spacecraft images to show that Saturn’s moon Enceladus may have tipped away from its original spin axis by 55 degrees – more than halfway toward rolling completely onto its side.

Cool preview of Pluto craft’s next target

On June 3, July 10 and July 17, astronomers will be watching as tiny MU69 in the outer solar system – the New Horizons spacecraft’s next target – occults or blocks the light from 3 different stars.

Your immune system in space

New video from NASA about studies looking at the effects of space travel on the human body’s immune system.