Billions and billions of Earth's, maybe this week on planetary radio. Hi everyone, welcome to Public Radio's travel show that takes you to the final frontier.

I'm at Kaplan. There is evidence that many, maybe even most of the

stars in our galaxy have rocky planets whirling around them. We'll talk with astronomer

Michael Meyer, who led the international team that found this evidence in dust.

Emily Lachowala explains why a blue sunset in a red sky is perfectly normal on Mars and Bruce Bats will join us for a special

mobile edition of What's Up with our usual guide to the night sky a new space

trivia contest and much more.

Bill Nye the Science Guy has the week off, he'll be back with a new commentary next time.

Peggy Whitson has come home, the first woman to command the International Space Station and her Russian companions

plunked down to Earth in a Soyuz capsule on April 19.

That capsule missed its intended landing point by a few hundred kilometers, but all is well. The capsule 377 days. She got in five spacewalks, too. There are doubters but a team of scientists

at the University of Rome claimed to have discovered the theorized particles that might be the essence of dark matter, that mysterious material that appears to make up so much of the universe's mass.

They believe that their new and improved detector found weakly interacting massive particles, otherwise known as wimps.

That still leaves dark energy to be explained.

So far no one has come up with a theoretical force explaining

that mystery. When they do, I hope they call it Dweeb. Speaking if mysteries, Emily Lachtoala

has an update on the pioneer anomaly in her blog at

planetary.org. Slava Tura chef and his coworkers at JPL have come up with a partial

explanation for the weird acceleration of the old Pioneer 10 spacecraft

some of it could be caused by uneven heat radiation

but this thermal modeling doesn't provide a full explanation. Next up Michael Meyer.

What if most of the stars in our galaxy have rocky planets?

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