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Great white shark and bluefin tuna, at Monterey Bay Aquarium. Courtesy of Niall Kennedy via Flickr.com

Shark and tuna convergent evolution

Lamnid sharks and tuna have similar physical traits that make them top ocean predators. But, a new study says, they took very different evolutionary paths.

Image via rapgenius.com

Today in science: E=mc2

Mass and energy are interchangeable.

Hoax image via social media.

No double moon in 2016, or ever

We thought we might get through this summer without the dumb hoax about Mars as big as a full moon rearing its head. But, no.

Kit Delauriers describes her self as a ski mountaineer. Image via The North Face.

Tallest peak in the US Arctic is …

No one knew whether Mount Chamberlin or Mount Isto was taller. Now an aerial study – and a ski mountaineer – declare a winner.

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Dates of lunar and solar eclipses in 2016

The next eclipse is an annular solar eclipse on September 1, 2016.

Total solar eclipse via Fred Espenak

How many eclipses in 1 calendar year?

Every calendar year has at least 4, but 5, 6 or even 7 eclipses are also possible. Why don’t we see them all?

Phobos, via Viking 1.  Image Credit:  NASA

Today in science: A moon for Mars

American astronomer Asaph Hall discovered Phobos, one of the two Martian moons, on this date in 1877. Did he imagine how well we’d see Mars’ moons today?

Image Credit: Jeffdelonge

Say hello to the death’s-head hawkmoth

It’s the insect star of The Silence of the Lambs.

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Upside down rainbow-like arcs

Circumzenithal arcs have been described as an “upside down rainbow” or “a grin in the sky.” They’re wonderful! See photos here.

Image via Michelle's blue planet

Lifeform of the week: Sea stars

You call them starfish? They’re brilliant by any name.