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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.

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.

Mammatus clouds in New Jersey. June 21, 2016. Image via Phil Chillemi.

Check out these mammatus clouds

Mammatus clouds can appear ominous. But, in a way that’s so common in nature, their dangerous aspect goes hand in hand with a magnificent beauty.

Lead study author Josh Stewart follows a giant oceanic manta ray at Bahia de Banderas off mainland Pacific Mexico. Image via Scripps Oceanography/ Octavio Aburto/ PBS

Surprise! Some mantas are homebodies

Oceanic manta rays have long been thought to migrate great distances. But Indo-Pacific mantas, at least, are more local commuters than long-distance travelers.

Red Phoenix, aka Vermilion Bird. Image via fantasticanimals.wordpress.com.

A Chinese perspective on summer

In Chinese thought, summer has been associated with the color red, the sound of laughing, the heart organ, the fire element and a red phoenix bird.

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Summer solstice tale of 2 cities

On the June solstice, the sun sets at the same time in New York City and St. Augustine, Florida. But New York has an hour more of daylight. How’s that happen?

EarthSky Facebook friend Jüri Voit Photography wrote on May 30, 2016: "Season of noctilucent clouds is open!"

The secrets of night-shining clouds

People at high latitudes are seeing glowing clouds in a dark night sky. They’re called noctilucent or “night-shining” clouds.

View larger. | Climatic cycles of ice and dust build the Martian polar caps, season by season, year by year, and periodically whittle down their size when the climate changes. This image is a simulated 3-D perspective view, created from image data taken by the THEMIS instrument on NASA's Mars Odyssey spacecraft. Image via NASA/JPL/Arizona State University, R. Luk.

Ice ages, and ice at Mars’ polar cap

Confirmation that Mars came out of its last ice age 400,000 years ago. Plus insights into the water cycle on Mars, a possible help to future space colonists.

Sunrise Stripe Hospital Hill, Mutare Zimbabwe 5-28-2016 Peter Lowenstein sq

Sunrise stripes on Hospital Hill, Zimbabwe

A rare combination of light and shade over a hillside in Mutare.

View larger. |

Old under-ice volcanoes on Mars

An oddly textured region of southern Mars is not ice-covered today. Yet landforms here – and now certain minerals – are associated with under-ice volcanoes.