Kuiper Belt Gets New Notches

A telescopic sky survey finds 14 previously unknown objects in and around the Kuiper Belt. John Matson reports

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The map of the solar system may be due for a little updating. A telescopic sky survey has turned up 14 new objects in and around the Kuiper Belt, the icy debris field out past Neptune. [Scott Sheppard et al., "A Southern Sky and Galactic Plane Survey for Bright Kuiper Belt Objects"]

The new trans-Neptunian objects, as they're called, are just the latest to revise our view of the outer solar system. The first Kuiper Belt object was spotted in 1992, but it was not until the middle of the last decade that the belt got its biggest notches. That's when astronomers turned up a handful of large trans-Neptunian objects that led to the creation of the "dwarf planet" category.

Some of the newfound objects may be large enough to qualify as dwarf planets. The key is that they need to be several hundred kilometers across, large enough to have settled into a round shape. So far there are just five confirmed dwarf planets, including the most famous Kuiper Belt object, Pluto. The new potential dwarfs will join several other candidates awaiting confirmation and recognition.

Astronomers will need more detailed observations to determine if any of the newfound objects are truly round. If so, they may be able to slip past the velvet rope and into the exclusive dwarf-planet club.

—John Matson

[The above text is a transcript of this podcast.]

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