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Where did Mars get its organic molecules?

New computer simulations indicate 1/3 of Mars’ organic molecules come from asteroids and comets.

Stunning Mars images, from Curiosity

The Curiosity rover has sent back some beautiful new images of the foothills of Mount Sharp in Gale crater on Mars.

Hubble finds relic galaxy close to home

The Hubble Space Telescope looks at a very rare and odd assemblage of stars that has remained essentially unchanged for the past 10 billion years.

Pluto craft’s next target is Ultima Thule

New Horizons passed Pluto in 2015. With public input, the mission team has nicknamed the spacecraft’s next target – on the fringes of our solar system – Ultima Thule.

A peculiar galactic clash

This pair of barred spiral galaxies have just begun a magnificent merger.

The most inspirational space video, ever

Worried that our human species is making a mess of things? Inspiration-less? Carl Sagan wants to tell you something.

360 video: Tour a Mars robot test lab

If your browser or smart phone is set up to view it, this 360 video will let you virtually explore a Mars simulation facility at NASA’s Jet Propulsion Laboratory, where engineers are practicing for an upcoming Mars lander mission.

Nature likes to make bow waves

Boats moving through water make bow waves. Objects in space, including Earth, make them, too. Even the moon’s shadow – penetrating Earth’s atmosphere during a total solar eclipse – creates moving bow waves.

Measuring universe expansion reveals mystery

Is something unpredicted going on in the depths of space?

Scientists expect 1st direct black hole image soon

This was the most popular post at EarthSky this week, and no wonder. It’s exciting! We’re holding our breaths for the 1st-ever direct image of a black hole’s event horizon, expected to be released in 2018.

Update on S2, the star plunging past the Milky Way’s black hole

Astronomers report no companion found for S2, the star orbiting near our Milky Way’s central black hole. It’s an “all-clear” for an exciting test of Einstein’s Theory of General Relativity.

Day meets night on Jupiter

The Juno spacecraft captured this image during its 11th close flyby of the planet. It shows swirling cloud formations around Jupiter’s south pole.

Send your name to the sun

NASA’s Parker Solar Probe, launching this summer, will travel closer to the sun than any spacecraft yet – and you can send your name along for the ride. Hear about it from William Shatner.

See asteroid 2017 VR12 as it swept past

Asteroid 2017 VR12 passed at 3.76 times the moon’s distance on March 7. Here are images and video of its sweep past Earth.

China’s Tiangong-1 due for uncontrolled re-entry, soon

The current estimated window for Tiangong 1’s re-entry is approximately March 29 to April 9, 2018. “This is highly variable,” according to ESA.

Views of home

Intriguing and inspiring perspectives of our home planet from spacecraft cameras looking back at Earth.

Today in science: Breakup of an asteroid

Scientists watched as, over a period of months, the asteroid known as P/2013 R3 broke into smaller pieces.

What is a runaway star?

For the most part, stars in our Milky Way galaxy move in a more or less orderly way. But some stars are runaways.

Why is Venus so bright?

Venus is the 3rd brightest object in the sky, after the sun and moon. Why?

A signal from the 1st stars

It’s potentially one of the most exciting astronomical discoveries of the decade. Astronomers have detected a signal from the 1st stars to form in the universe.