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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?

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.

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 stripes on Hospital Hill, Zimbabwe

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

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.

Why Planet 9 shouldn’t exist

Earlier this year, scientists presented evidence for a Planet Nine in the far outer solar system. Scientists think it exists, but – if so – how did it get there?

Today in science: Neil Armstrong’s close call

On May 6, 1968 – more than a year before his famous first moonwalk – Neil Armstrong narrowly escaped disaster while training in the Lunar Landing Research Vehicle.

A pure methane sea on Titan

We knew that Saturn’s moon Titan had seas and lakes of liquid hydrocarbons, but their exact composition was unknown until recently.

Orbit like a comet, rocky like an asteroid

They’re calling it a Manx comet, after the cats with no tails. It may have formed in the inner solar system and been ejected outward.

Astronomical events in 2016

A month by month listing of major moon phases, conjunctions, oppositions, meteor showers and other important dates, from astronomer Fred Espenak.