A Prediction for Pluto: More Moons

[MzKittyKath]

Scott J. Kenyon, an astrophysicist at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass., has a prediction about Pluto: NASA's New Horizons spacecraft will discover more moons.

A new paper by Dr. Kenyon and Benjamin C. Bromley of the University of Utah pinpoints places where moons — and even rings, like a miniature version of Saturn's — could be lurking around Pluto.

Within a week or so, Dr. Kenyon will likely know whether he is right or wrong.

Pluto has five known moons, more than Mercury, Venus, Earth and Mars put together. The biggest was discovered from a telescope on Earth in 1978; the four smaller ones were spotted in the last decade by the Hubble Space Telescope, which is in orbit around Earth.

The team working on New Horizons, which will fly by Pluto on Tuesday, has assiduously searched for additional moons and so far has found none. That is both a relief — moons and smaller debris are potential dangers to a spacecraft speeding at 31,000 miles per hour — and a surprise.

"It's as clean as a whistle," said S. Alan Stern, the principal investigator for New Horizons.

"Isn’t it just amazingly coincidental to you," Dr. Stern said, "like it is to me and others here, that we were just barely able to see the smallest satellite from Earth and there was nothing else?"

The telescopic camera on New Horizons can already spot objects as small as a mile across, and it will be even more eagle-eyed as it approaches.

Dr. Kenyon, who is not on the New Horizons team, has a second prediction about Pluto: "It will have a lot of craters."

That is not going out on a limb. Stuff runs into everything in the solar system, and Pluto is unlikely to have any geological processes that could erase impact craters like a shaken Etch-a-Sketch.

Tune in in the next few days to find out what reality has revealed.

--KENNETH CHANG

 

by NEWYORK TIMES http://www.nytimes.com/interactive/projects/cp/summer-of-science-2015/latest/a-prediction-for-pluto-moons