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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.

Close and far moons in 2016

A little-known fact about the intriguing cycle of far and close moons, plus dates for 2016’s 14 lunar apogees (far moons) and 13 lunar perigees (near moons).

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.

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.

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.

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.


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.


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.

Pillars of Creation 1995, via Hubble

The awesome beauty of the Eagle Nebula

Here is the famous Pillars of Creation photo taken by the Hubble Space Telescope. It’s one of the features within the Eagle Nebula.

Realtime snapshot of wind currents over USA. July 15, 2016 at 9:35 EDT

Watch wind flowing across US in real time

The wind map updates every hour and lets you see the movement, flow, and speeds of wind across the United States. Go see it! It’s great!

Several Indian Ocean rockskippers (Alticus monochrus), on a rock at the intertidal zone in Mauritius. Image via Georgina M. Cooke.

Many fish evolved to survive on land

“A fish out of water might seem an extraordinary thing, but in fact it is quite a common phenomenon,” said these researchers.

The extra second - or leap second - is added to world clocks one second before midnight, UTC.

2016 will have a leap second

Delay those New Year’s plans. World timekeepers have announced they’ll add a leap second just before midnight on December 31, 2016.