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Posts by Larry Sessions

Antares and M4 image by stargazerbob@aol.com
Tonight | Jul 02, 2015

Antares is Heart of the Scorpion

The ruby Heart of Scorpius is the 16th brightest star in our sky and one of the most gigantic stars known.

clock_almost_midnight
Science Wire | Jun 29, 2015

Leap second scheduled for June 30

World timekeepers will add one extra second on June 30, 2015. Meanwhile, a proposal to dump the leap second has been deferred until October.

Telescopic view of daytime Venus (l) and moon via NASA
Science Wire | Jun 19, 2015

Venus and Jupiter dance in daylight

Most of us think only of viewing planets at night, but sometimes you can catch them in broad daylight! The next great chance to do that is Saturday, June 20.

The sun in extreme ultraviolet, false color green
Science Wire | Jun 14, 2015

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!

Artist's concept of Kochab seen from its planets via ESky
Tonight | Jun 10, 2015

Kochab and Pherkad

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

Alpha Centauri
Tonight | May 19, 2015

Alpha Centauri, closest star system 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.

Arcturus.
Tonight | May 13, 2015

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.

2015-april-24-jupiter-castor-pollux-moon-night-sky-chart
Tonight | Apr 24, 2015

Moon near Gemini stars on April 24

Tonight’s moon is approaching the stars Castor and Pollux in the constellation Gemini the Twins. These stars represent twins in many cultures.

Artist's concept of Spica from hypothetical planet
Tonight | Apr 22, 2015

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.

Image via New Scientist
Science Wire | Apr 14, 2015

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!