First Binary-Binary Solar System Discovered

Posted: November 7, 2016 by oldbrew in Astrophysics
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A 'normal' binary system

A ‘normal’ binary system

Have fun trying to imagine how this solar system works, as iTech Post describes its unusual structure.

Astronomers have discovered the first binary-binary solar system. The discovery is said to have implications on the way people perceive the solar system was formed.

The discovered solar system has two stars as well and a planet revolving. The new binary system has been named HD 87646. It is made up of one star, a brown dwarf star, and a massive planet, according to Science Daily. The large planet is 12 times the mass of Jupiter while the brown dwarf is 57 times the mass of Jupiter. The two are in close proximity as well to the primary star.

What makes the system interesting is that it defies what people know how a solar system is. Typically astronomers think that the solar system formed out of a disk dust cloud, with the large outer planets farther out from the primary star. Yet with HD 87646 the objects are far closer than how the outer planets are in our solar system.

HD 87646 is a binary star system, but the two stars are in close proximity to each other. The larger star is 12 percent more massive than the Sun, while the second is around 10 percent less massive than the Sun, as Phys Org reports. The distance between the two stars is only 22 astronomical units away. That is equivalent to the distance between the Sun and Uranus.

It has been observed that such a distance in astronomical terms is quite close to a binary star system. This becomes even more complex when a planet is orbiting the primary star as well. The arrangement of HD 87646 then defines what people know a solar system to be since the two stars are too close to each other and with a planet revolving around it as well.

The discovery has been made by University of Florida Professor Jian Ge along with Bo Ma. The star system was first surveyed in 2006 during the Multi-object APO Radial Velocity Exoplanet Large-area Survey (MARVELS). It was discovered with the help of the Doppler instrument W.M. Keck Exoplanet Tracker, or KeckET. The large planet has been named MARVELS-7a while the brown dwarf is called MARVELS-7b.

Source: First Binary-Binary Solar System Discovered : Science : iTech Post

Talkshop note: there’s an interesting 4-minute video on binary stars at the end of the linked report.

  1. oldbrew says:

    Here’s Algol a boring old triple star system 😉

    It gave rise to the Algol paradox…

    ‘The paradox is resolved by the fact that in many binary stars, there can be a flow of material between the two, disturbing the normal process of stellar evolution.’

  2. oldbrew says:

    Exoplanet hunters are missing 75 per cent of two-star worlds

    ‘…binaries have more moving parts. The planet could orbit its stars in the same plane, or adopt its own separate plane. The angle of its orbit with respect to the stars’ plane shifts with each trip around the binary. Sometimes the planet will transit as it goes around. Sometimes it won’t.’