Le Poids du Réel

June 6, 2006—Our solar system could have its own "mini-me" floating in the vast reaches of space.

That's the theory being proposed by a team led by a University of Toronto astronomer, whose latest research reveals that planetary nurseries could exist not only around stars, but also around planet-size objects about a hundred times less massive than our sun.

The work focused on newly formed planetary mass objects, or planemos—objects with about the same masses as planets that do not orbit stars—as envisioned by this artist's conception.

Young planemos are similar to stars in that they are still very hot from the energy it takes to form and are surrounded by disks of debris. The disks contain the raw materials for planet-making, suggesting to scientists that miniature versions of the solar system could orbit planemos that are not much larger than Jupiter.

The finding complements previous research showing a potentially planet-forming disk around a brown dwarf—a star that didn't grow large enough to ignite. (Read "'Diamond Planets' Hint at Dazzling Promise of Other Worlds.")

But the researchers note that as planemos age and cool, prospects for life on the objects' tiny progeny would be dim.

Without the heat radiated by a fully formed star, "any kind of planet that forms around them is committed to an eternal freeze," lead author Ray Jayawardhana told the Reuters news agency.

—Victoria Gilman

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