Binary and Multi-Star Systems

A binary is a pair of stars that orbit each other. A multi-star system consists of three or more stars. The stars in a binary or a multi-star system all formed from a single cloud of gas and dust, so they are true "siblings."

Featured Images

Hubble Space Telescope view of the Gliese 229 system
Faint Neighbors Sunday, February 7, 2016
Animated view of an erupting black hole
Big Gulp Aftermath Tuesday, September 15, 2015
The system V664 Cassiopeia is creating a planetary nebula
Bread Crumbs Thursday, July 23, 2015
Artist's concept of Alpha Centauri A and B, plus a planet
Busy Neighbor Monday, May 25, 2015
Artist's concept of MY Camelopardalis, a contact binary star system
Close Twins Sunday, March 15, 2015
Superflare on one of the stars of DG Canum Venaticorum
Tiny Star, Big Outburst Wednesday, December 3, 2014
Artist's concept of Epsilon Aurigae
Playing Frisbee Sunday, November 23, 2014
Hubble Space Telescope view of Eta Carinae
Future Fireworks Monday, June 16, 2014
Black-widow pulsar
Doomed Mate Thursday, April 10, 2014
Artist's concept of black hole binary star system in the galaxy M101
Brilliant Darkness Thursday, January 16, 2014
Illustration depicts the contact binary system W Ursae Majoris
Two-for-One Offer Wednesday, August 15, 2012
The Necklace Nebula, the remains of a dying star in Sagittarius
Ring of Fire Monday, August 15, 2011
Delta Lyrae and the Summer Triangle
Seeing Double Sunday, July 10, 2011

Radio Programs

Faint Neighbors Two close but faint neighbors Sunday, February 7, 2016
Moon and Regulus A stellar “king” and his entourage Monday, January 25, 2016
Procyon The revenge of the scrawny Saturday, January 23, 2016
R Sculptoris Stirring up a stellar bubble Friday, December 11, 2015
Capella A little goat crosses the sky Sunday, November 15, 2015
Runaway Star A stellar “runaway” in the charioteer Saturday, November 14, 2015
Moon and Spica Keeping away from a bright pair of stars Sunday, November 8, 2015
Sheratan The hidden nature of a binary star Sunday, October 25, 2015
Homunculus Nebula A giant star blows giant bubbles Wednesday, October 21, 2015
Rare Gems Yellow gems from the water bearer Saturday, October 3, 2015
Mirach Stars at opposite ends of the scale Tuesday, September 29, 2015
Dabih A dizzying system of stars Wednesday, September 23, 2015
More Andromeda Galaxy Getting ready to put on a show Thursday, September 17, 2015
Waking Up A black hole wakes up hungry Tuesday, September 15, 2015
Alpha Centauri Planet Taking the measure of a planet Saturday, September 12, 2015
Luminous Red Novae One star born from two Thursday, September 3, 2015
Making a Magnetar Making a powerful magnet Thursday, August 6, 2015
Delta Cephei A surprise from a well-known star Monday, August 3, 2015
Delta Cygni Spreading out a stellar trio Friday, July 31, 2015
Future Outbursts Setting up future outbursts Friday, July 24, 2015
Bread Crumbs Leaving a trail of breadcrumbs Thursday, July 23, 2015
The Stinger The scorpion’s bright stinger Sunday, July 19, 2015
Doomed Stars Two stars with a bright future Wednesday, June 17, 2015
Small but Bright Tiny stars put on brilliant displays Tuesday, June 16, 2015
Alpha Centauri Putting three stars on the scales Monday, May 25, 2015
Moon and Leo “Weighing” two giant stars Sunday, May 24, 2015
Future Quadruplets A star cloud prepares to give birth Thursday, April 16, 2015
Moon and Regulus The intertwined lives of two stars Monday, March 30, 2015
MY Camelopardalis A brilliant duet for the giraffe Sunday, March 15, 2015
Moon and Spica Safety first around an amazing star Sunday, March 8, 2015
Morning Moon A bright future for the scorpion Thursday, February 12, 2015
Bright Merger The fireworks of a hostile takeover Wednesday, February 11, 2015
Beta Monocerotis A brilliant set of triplets Tuesday, February 10, 2015
Procyon One dog leads another across the sky Saturday, January 24, 2015
Orion’s Head Heading for the top of the hunter Sunday, January 18, 2015
Robert Aitken An astronomer who saw double Wednesday, December 31, 2014
Alhena The bright foot of a celestial twin Sunday, December 28, 2014
Superflares A big outburst from a tiny star Wednesday, December 3, 2014
Rara Avis II Dancing with the firebird Sunday, November 30, 2014
Epsilon Aurigae Playing Frisbee with a bright star Sunday, November 23, 2014
Moon and Companions Feeble companions for a bright star Friday, November 14, 2014
Brighter A bright star gets even brighter Tuesday, November 4, 2014
More Capella Bright giants with a shared evolution Sunday, October 26, 2014
Fomalhaut II Faint companions for a bright star Thursday, October 2, 2014
Moon and Regulus Keeping an old star looking young Saturday, September 20, 2014
Rasalhague The head of the serpent bearer Sunday, September 7, 2014
Dabih Covering up a passel of stars Friday, September 5, 2014
Sigma Scorpii Impressive stars near the scorpion’s heart Saturday, August 9, 2014
Moon and Companions The scorpion’s southern claw Sunday, August 3, 2014
Different Explosions Exploding stars with a difference Saturday, July 19, 2014
Zombie Stars The night of the living dead stars Thursday, July 17, 2014
Alphecca Stellar siblings with different futures Saturday, June 28, 2014
Close Quartet A nearby stellar quartet Sunday, June 22, 2014
Eta Carinae II Aggravating a supergiant star Tuesday, June 17, 2014
Eta Carinae Building up to a big eruption Monday, June 16, 2014
Moon and Spica Two stars with big futures Sunday, June 8, 2014
Moon and Regulus A stellar whirling dervish Tuesday, June 3, 2014
Companionship Looking for stellar companions Thursday, May 29, 2014
Too Close Getting too close to a dark monster Sunday, May 18, 2014
Rasalhague A preview of coming attractions Saturday, May 17, 2014
Black Widow Pulsars Celestial creepy-crawlies Thursday, April 10, 2014
Heart of Charles Stirring up the Heart of Charles Saturday, March 22, 2014
Castor Rare sextuplets among the stars Saturday, March 1, 2014
Monoceros A vision in blue in the unicorn Tuesday, February 25, 2014
Moon and Spica A star of the first magnitude Tuesday, February 18, 2014
Dubhe A bright orphan in the Big Dipper Saturday, February 15, 2014
EX Hydrae Two small but busy stars Thursday, December 19, 2013
Super Origins A refugee from the planet Krypton Saturday, December 14, 2013
Sirius Rising The right season for the Dog Star Friday, December 6, 2013
Capella A pair of bright, “puffy” stars Tuesday, November 19, 2013
Andromeda A colorful stellar quartet Wednesday, November 6, 2013
Fomalhaut Surprises from a well-studied star Monday, October 14, 2013
Merging Stars Two stars that become one Saturday, October 5, 2013
ER Vulpeculae Two stars locked in a tight embrace Friday, September 27, 2013
Equuleus Two stars whose fates are intertwined Saturday, August 24, 2013
Sheliak A stellar tug-of-war Thursday, August 1, 2013
Black Hole Beacon A black hole announces its presence Thursday, July 25, 2013
Zubenelgenubi A complex claw for the scorpion Sunday, July 14, 2013
Moon and Regulus The lion’s quadruple heart Thursday, July 11, 2013
Albireo A colorful stellar duo Saturday, July 6, 2013
Northern Crown Crowning the night sky Wednesday, May 29, 2013
Moon and Spica Neighbors that stir things up Wednesday, April 24, 2013
Moon and Regulus Putting the squeeze on a star Saturday, March 23, 2013
Cracking Up A neutron star cracks up Friday, March 22, 2013
Four Suns A world with four suns in the sky Friday, March 8, 2013
Ringing Beat The beat of vibrating stars Wednesday, March 6, 2013
Moon and Antares Two stars with different fates Sunday, March 3, 2013
Moon and Regulus A different kind of star system Sunday, February 24, 2013
Procyon A pair of stellar light bulbs Friday, February 22, 2013
Castor Three sets of stellar twins Tuesday, January 15, 2013
Moon and Spica Giant tides on giant stars Friday, January 4, 2013
Capella Bright stars with a bright future Thursday, December 6, 2012
Venus and Spica A star that’s more than meets the eye Saturday, November 17, 2012
Triangulum Aging stars in the triangle Saturday, November 3, 2012
Halloween Star II A stellar cannibal for Halloween Wednesday, October 31, 2012
Halloween Star A two-headed stellar demon Tuesday, October 30, 2012
Tiny Black Hole A record-setting black hole Friday, October 26, 2012
Faint Triplets A faint set of stellar triplets Sunday, October 7, 2012
Gamma Cephei The top of the king’s starry house Sunday, September 2, 2012
Contact Binaries III A star system with a lot of variety Friday, August 17, 2012
Contact Binaries II Stirring up the family dynamics Thursday, August 16, 2012
Contact Binaries Stars that can’t let go Wednesday, August 15, 2012
Cygnus X-1 A giant star vanishes from view Wednesday, August 1, 2012
Colorful Beak The swan’s colorful beak Tuesday, July 31, 2012
Equuleus Drawing up a little horse Sunday, July 29, 2012
Moon and Spica Two bright stars for the price of one Wednesday, July 25, 2012
Zippy Planets Getting a big kick from a black hole Thursday, June 28, 2012
Capella A quick exit for a “heavy” star Friday, April 27, 2012
Supernova 1987A, III A picture-perfect stellar explosion Thursday, February 23, 2012
Sirius B A close companion for a bright star Tuesday, January 31, 2012
Moon and Hyades Staring into the face of the bull Thursday, January 5, 2012
More Moon and Companions An exciting future for a pair of stars Monday, December 19, 2011
Menkalinan The charioteer’s double-jointed shoulder Sunday, December 4, 2011
Rarae Aves II Dancing with the firebird Tuesday, November 29, 2011
Halloween Ghouls Ghoulish delights in the sky Monday, October 31, 2011
Too Close Getting too close to a black hole Tuesday, September 20, 2011
Evening Lineup II A pair of “pointy” stars Thursday, September 1, 2011
Scorpius Nova A bright stellar merger Monday, August 29, 2011
V404 Cygni A dark star system that puts on a show Sunday, August 14, 2011
61 Cygni Possible homes for neighbors Saturday, August 13, 2011
Moon and Companions Living under brilliant suns Thursday, August 4, 2011
Moon and Companions Stars and planets move apart Friday, June 10, 2011
Algieba The lion's double forehead Saturday, May 21, 2011
Castor The twins and triplets of Gemini Monday, May 16, 2011
Gamma Virginis A beautiful celestial double Thursday, May 12, 2011
Alphecca Overpowering a bright star Thursday, April 28, 2011
Alphard Getting dumped on by a neighbor Sunday, April 24, 2011
Moon and Spica Stirring up two stellar companions Sunday, April 17, 2011
Moon and Regulus Catching a stellar carnival ride Wednesday, April 13, 2011
Epsilon Aurigae A long-lasting stellar eclipse Monday, March 28, 2011
Dubhe Skies as different from ours as night and day Wednesday, February 23, 2011


Libra, the Scales Libra represents a balance scale. The name may...


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