"Impossible" Binary Stars Discovered

[LiminalMask]

"Astronomers working with the United Kingdom Infrared Telescope on Hawaii have discovered four pairs of stars that orbit each other in less than 4 hours."

Interesting tidbid from the article for Travellers: "It is possible that the magnetic field lines radiating out from the cool star companions get twisted and deformed as they spiral in towards each other, generating the extra activity through stellar wind, explosive flaring and star spots. Powerful magnetic activity could apply the brakes to these spinning stars, slowing them down so that they move closer together."

Also, I did not know that half of the Milky Way's star systems are binaries!

Article here.

 

[McPerth]

Interesting article.

About half of the stars in our Milky Way galaxy are, unlike our Sun, part of a binary system in which two stars orbit each other

Half of the stars, but that means about one third of the systems (as each binary system has 2 stars)...

 

[G. Kashkanun Anderson]

Half of the stars, but that means about one third of the systems (as each binary system has 2 stars)...

Chandra estimates that up to 80% of all stars in the Milky Way galaxy are a part of multiple systems.

I think the problem is that you are expecting a higher level of linguistic precision than the author intended. My guess is that he actually did mean 50% of all star systems by that statement.

 

[BlackBat242]

I know they have found trinary systems... have they found any quad or quint systems?

 

[aramis]

I know they have found trinary systems... have they found any quad or quint systems?

several suspected - but the orbits of the suspected hexinary system have the orbits of 4 suspected companions being measured in centuries and orbital distances measured in multiple hundreds of AU.

 

[Fritz_Brown]

Wonder if we'll see any rosettes? Or some of the other really odd ones?

 

[aramis]

Wonder if we'll see any rosettes? Or some of the other really odd ones?

Unlikely... the hextuple system of Castor is essentially, in traveller terms, a trinary composed of 3 close binary pairs.

Aa: A1 V
Ab: M5 V [or A Dwarf - not conclusively typed yet]
Ba: A2 Vm
Bb: M2 V
Ca: M0.5 Ve Red Dwarf
Cb: M0.5 Ve Red Dwarf

Aa to Ab distance: 0.022 AU - Orbit ≤-1, 9.21 day orbit.
Ba to Ba distance 0.030 AU - Orbit ≤-1, 2.93 day orbit
Ca to Cb distance 0.018 AU - Orbit ≤-1, 19.5 hour orbit.


Aab to Bab distance 107.0 AU - Orbit 10.5, 467 year orbit
AabBab barycenter to Cab: 1100 AU, Orbit ≥10,000. years...

http://www.solstation.com/stars2/castor6.htm
http://en.wikipedia.org/wiki/Castor_(star)

 

[saundby]

I know they have found trinary systems... have they found any quad or quint systems?

Here's one of my favorites to show the public at Star Parties:
Beta Scorpii.