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Posts by Larry Sessions

The sun in extreme ultraviolet, false color green
Science Wire | May 21, 2015

10 things you might not know 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
Tonight | May 19, 2015

Star of the week: 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!

You need a dark sky to appreciate the constellation Coma Berenices.  If you have one ... it's very beautiful.
Tonight | Apr 13, 2015

Leo loses his tail. We gain a constellation

A clump of faint stars trailing the constellation Leo once represented the Lion’s tail – but now these stars are known as Coma Berenices, the hair of a queen.

Coma Cluster of galaxies by Justin Ng.
Tonight | Apr 06, 2015

Coma Cluster of galaxies

The Coma Cluster is one of the richest galaxy clusters known. How many suns and how many worlds might be located in this direction of space?

Constellation Crux photo by Christopher J Picking in New Zealand.  More information about this photo here.  Used with permission
Tonight | Apr 01, 2015

Mimosa is second-brightest in Southern Cross

If you’re in the U.S., you must be at about New Orleans’ latitude to glimpse it. From the southern hemisphere, Mimosa is a prominent and beloved star.

Constellation Crux photo by Christopher J Picking in New Zealand.  More information about this photo here.  Used with permission
Tonight | Mar 24, 2015

Acrux, brightest star in Southern Cross

You have to be in the Southern Hemisphere to see Crux – the Southern
Cross – in all its glory. Bluish Acrux, aka Alpha Crucis, is its brightest star.