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Image via NASA/SDO

Trio of solar flares

The sun emitted 3 mid-level solar flares on July 22-23, 2016. This is what NASA’s Solar Dynamics Observatory saw.

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Where are Ceres’ large craters?

There’s a curious lack of big craters on the dwarf planet Ceres, largest body in the asteroid belt between Mars and Jupiter. Why?

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New China telescope to search for aliens

A 1,600-foot (500-meter) dish called FAST – in southwest China – is now the world’s largest radio telescope. It’s expected to be fully operational in September.

An experimental rocket test over Scandinavia in 2009, which triggered many UFO reports. Read more about this photo.

If it’s not a UFO, what is it?

Most Unidentified Flying Objects aren’t unidentified at all. Here’s a list of natural and human-made objects in the sky that people frequently mistake for UFOs.

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Cloud study reveals Venus’ surface

Scientists had suspected that mountains on Venus affected weather patterns seen rippling across Venus’ cloudtops. A new study provides evidence of this connection.

Image via NASA

A year of Earth from a million miles

Watch a full year of Earth’s sunlit side, seen from a million miles away by the DSCOVR spacecraft.

WISE all-sky image of Milky Way galaxy. The circle is centered on the galaxy's central region. The inset shows an enhanced version of the same region that shows a clearer view of the X-shaped structure. Image via NASA/JPL-Caltech; D. Lang/Dunlap Institute.

The X at the center of the Milky Way

Computer models, and observations of our galaxy and others, suggested a Milky Way X, made of stars. An analysis of data from the WISE space telescope reveals it.

The lunar Mare Imbrium, or Sea of Rains, via Pete Lawrence's Moon guides.

Protoplanet blasted out Mare Imbrium

Mare Imbrium basin on the moon – the Man in the Moon’s right eye – might have been made by a protoplanet-sized impact, 3.8 billion years ago.

View full image. | First photograph ever taken from surface of Mars, by the Viking 1 lander shortly after it touched down on July 20, 1976. Image via NASA.

Today in science: 1st Mars landing

40th anniversary of the first fully successful soft landing on Mars’ surface, by the Viking 1 spacecraft. First images from Mars’ surface, here.

The world watched on television as Neil Armstrong took the first steps on the moon's surface on July 20, 1969.  It was the first time humans walked another world.  As he stepped onto the lunar surface, Armstrong said, "That is one small step for [a] man, one giant leap for mankind."

Today in science: 1st footsteps on moon

Today is the 47th anniversary of humanity’s historic first steps on the moon. The story in pictures, here.