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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.

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.

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.

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?

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?

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.

Today in science: Launch of Sputnik

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

Clues to ancient earthquakes in caves

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