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Simulated image of moon on November 21, 2016 via the US Naval Observatory

Last quarter moon 3rd of 4 this season

Usually there are only 3 last quarter moons in a season. The November 21, 2016 last quarter moon, though, counts as the 3rd of four.

Birth of Surtsey in 1963 via NOAA.

Today in science: An island is born

On November 14 1963, crew aboard a trawler sailing near Iceland spotted a column of smoke rising from the sea surface. A new island, Surtsey, was being born.

Via Wikimedia Commons

Seeing things that aren’t there

Seeing animals in clouds, or a face in the moon, are examples of pareidolia. Look here for photos to test your own ability to see things that aren’t there.

A 1585 map of Iceland created by Abraham Ortelius. Image via Wikimedia Commons.

Mount Hekla was called Gateway to Hell

Mount Hekla is Iceland’s 3rd most active volcano. A large eruption in 1104 earned it the moniker Gateway to Hell. Is Mount Hekla overdue for another eruption?

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Can you see lights of Diwali from space?

The Hindu festival of Diwali was October 30, 2016. It’s a festival of light! But can you see the light of Diwali from space?

The moon's orbit around Earth is not a perfect circle.  But it is very nearly circular, as the above diagram shows.  Diagram by Brian Koberlein.

2016’s longest lunar month starts October 30

Lunar months vary in part because the moon’s orbit around Earth isn’t a perfect circle. Longest (and shortest) lunar months in 2016, here.

The general flow of global ocean circulation, with warm surface currents in red, and cold deep ocean currents in blue.Warm salty surface water from the Caribbean moves to the northern Atlantic Ocean, releasing heat to the atmosphere in those far nothern latitudes, then sinks to continue its journey as a cold south-moving current. Image via USGS.

Warm ocean currents are slowing down

Satellite data and ocean sensors show a definite slowdown since 2004 in ocean currents that warm eastern North America and western Europe.

Canela (left) and Blanquita (right) don’t need symbols to express their opinions. Image credit: Dominique Brand.

How to ask a horse what it wants

Do you want a blanket? Norwegian researchers recently described how they trained horses to use symbols to answer that question.

sputnik-1-technician-cp

Today in science: Launch of Sputnik

Sputnik’s unassuming beep ushered in the Space Age. Hear it here.

Donnehue's Cave in Indiana. Image Credit: Sam Frushour.

Clues to ancient earthquakes in caves

Stalagmites on the floors of caves in southern Indiana contain evidence of past earthquakes, scientists say.

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.