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Posts by Larry Sessions

Photo Credit:  A. Dupree, R. Gilliland, NASA
Science Wire | Feb 05, 2016

How far is Betelgeuse?

Finding star distances isn’t easy. Here’s how it’s done, and why astronomers recently modified the distance estimate to the famous star Betelgeuse.

Canopus seen from ISS
Tonight | Feb 04, 2016

Will you see Canopus?

Canopus is sky’s second-brightest star and easy to spot on February evenings, if …

Betelgeuse imaged in ultraviolet light by the Hubble Space Telescope and subsequently enhanced by NASA. The bright white spot is likely one of this star's poles. Image via NASA/ESA.
Science Wire | Jan 26, 2016

Betelgeuse will explode someday

Someday, the star Betelgeuse will run out of fuel, collapse under its own weight, and then rebound in a spectacular supernova explosion. Someday … but probably not soon.

Capella system, via Atlas of the Universe
Tonight | Jan 15, 2016

Capella is two golden stars

We see Capella as the brightest star in the constellation Auriga the Charioteer. It is really two stars, each with a golden color similar to our sun.

11jan10_430
Tonight | Jan 10, 2016

Faint, fuzzy star cluster near Sirius

Throughout January, look for a faint fuzzy object near the bright star Sirius. It’s called M41, and it’s a star cluster masquerading as a comet.

Blue-white Rigel via Clark Planetarium
Tonight | Jan 06, 2016

Rigel in Orion is blue-white

We couldn’t live as close to Rigel as we live to our sun, because Rigel is nearly twice as hot – and about 40,000 times brighter – than our local star.

large_magellanic_cloud2
Tonight | Jan 04, 2016

The spectacular Large Magellanic Cloud

From tropical or Southern Hemisphere latitudes, the Large Magellanic Cloud is easy to see. Look for it in the evening from December to April.

Aldebaran-Sun_comparison_cropped
Tonight | Dec 29, 2015

Aldebaran is the Bull’s fiery eye

If Aldebaran were placed where the sun is now, its surface would extend almost to the orbit of Mercury.

Credit: Russell Croman
Science Wire | Dec 23, 2015

Was the Christmas Star real?

A wondrous star has grown to be a major symbol of Christmas around the world. But what was it, really?

capella-aldebaran-taurus-auriga-december-evenings
Tonight | Dec 09, 2015

Can you see stars’ different colors?

Winter is the perfect season for noticing the colors of the stars. Never noticed them? Our sky chart can help guide your eye.