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Catch Comet Encke this evening!

The comet’s orbital period is short – only 3.3 years – and the orbit is relatively close to Earth. Encke’s Comet is now on its 63rd known visit to our part of space.

What is the crater-dome illusion?

When you see spacecraft images of craters on other worlds, do you sometimes think they look like domes? Here’s how to change your perception.

This date in science: Supernova 1987A

Supernova 1987A first appeared in earthly skies 30 years ago today. It was the closest observed supernova since 1604.

Wow! Nearby TRAPPIST-1 has 7 planets

Big discovery! NASA’s Spitzer Space Telescope has revealed 7 Earth-sized planets orbiting a tiny star only 40 light-years away. Three of them are firmly in the habitable zone.

What would life be like near TRAPPIST-1?

The newly discovered exoplanets orbiting this nearby star are likely to be bathed in high-energy ultraviolet radiation. What would life be like there? An expert explains.

Brightest, farthest pulsar found!

In one second, this distant pulsar – the spinning remains of a once-massive star – emits the same amount of energy as that released by our sun in 3.5 years.

Help astronomers look for Planet 9

There might be an unknown 9th planet that orbits far from Earth, on the outer fringes of our solar system. You can help astronomers find it, if it exists!

Today in science: John Glenn

On February 20, 1962, John Glenn became the 1st American to orbit Earth and the first American space hero.

Watch SpaceX Dragon launch February 18

SpaceX is scheduled to launch its Dragon spacecraft resupply mission to the International Space Station no earlier than 10:01 a.m. EST (1501 UTC) on Saturday, February 18. How to watch.

Compare sizes of sun and stars

It’s hard to comprehend the sheer size of objects in space, but take 2 minutes and give it a try!

Slooh astronomers catch comet breakup

Will comet 73P/Schwassmann-Wachmann survive its March 16 sweep near the sun, or disintegrate into a trail of cosmic dust?

Round object crosses the moon

During Friday’s penumbral eclipse of the moon, an observer in Puerto Rico captured images of a black disk moving across the moon’s face.

Hints of a quiet, stray black hole

Theoretical studies predict 100 million to 1 billion black holes in our Milky Way galaxy. So far, astronomers have found about 60. A serendipitous discovery could lead to finding more.

Green Comet 45P: Photos and video

Green Comet 45P has been in our sky for months and passed closest on February 11, 2017. It’s a faint one, but intrepid astronomers have captured some wonderful images!

Full braking at Alpha Centauri

Space visionaries might have figured out a way to travel within decades to the nearest star system, Alpha Centauri. But, once we get there, how do we slow down?

Possible to have 3 eclipses in 1 month?

In 1 calendar month, 3 eclipses are rare. But in 1 lunar month, 3 eclipses are are more common. From 2000-2050, it happens 14 times.

Why no eclipse every full and new moon?

This year, in 2017, there are 12 full moons and 12 new moons, but only four eclipses – two lunar and two solar.

Northern U.S. meteor dazzles thousands

Early Monday morning, thousands of people across multiple northern U.S. states watched a brilliant meteor streak across the sky. It then plunged into Lake Michigan.

Today in science: Great Meteor Procession

The February 9, 1913 meteors crossed the sky in formation, on nearly identical paths. Their pace across the sky was described as “stately” and “measured.”

What is retrograde motion?

Retrograde motion of Jupiter or Mars or Saturn in our sky is an illusion, caused by Earth’s passing these slower-moving outer worlds. But there’s a real retrograde motion, too.