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Larry Sessions
Artist's concept of Kochab seen from its planets via ESky

Kochab and Perked, guardians of north

Two noticeable stars in the Little Dipper are said to guard the north celestial pole because they circle so close to Polaris.

Nearly first quarter moon on the evening of June 11, 2016. The moon reached the first quarter phase on June 12, 2016 at 0810 UTC, or 3:10 a.m. CDT.  Translate to your timezone.

Quarter moon or a half moon?

Half the moon always faces us. And half the moon is always lit by the sun. But, in the language of astronomers, there are no ‘half moons.’

Stars. Image via NASA

Top 10 cool things about stars

Here’s a collection of 10 unexpected, intriguing facts about the stars of our universe – including our sun – that you probably didn’t know!

Alpha Centauri

Alpha Centauri, closest to our sun

Third star in the system, a red dwarf called Proxima Centauri, is our sun’s closest neighbor at about 4.22 light-years.

Artist's concept of the star Arcturus

Arcturus cuts through galaxy’s disk

Arcturus is cutting perpendicularly through the galactic disk at a tremendous rate of speed – some 150 kilometers per second.

alpha-beta-centauri-southern-cross

Hadar is a southern pointer star

Hadar, aka Beta Centauri, joins Alpha Centauri in pointing to the Southern Cross. It’s a triple system. Two of its stars will someday become nearby supernovae.

Artist's concept of Spica from hypothetical planet

Spica is a whirling double star

Spica is a binary star, with two stars larger and hotter than the sun, telescopically indistinguishable from a single point of light.

Crab Nebula

Crab Nebula was an exploding star

The Crab Nebula, located some 6,500 light years from Earth, marks the remains of a massive star observed to explode as a supernova in AD 1054.

Image via New Scientist

10 surprises about our solar system

A collection of 10 unexpected and intriguing facts about our solar system – our sun and its family of planets – you probably did not know!

2016-april-moon-castor-pollux-procyon

Moon near Gemini stars on April 13

Tonight’s moon is approaching stars Castor and Pollux in the constellation Gemini the Twins. Pollux is brighter and golden in color. Castor is pure white.