The Dark Mystery of Dark Matter this week on planetary radio. Hi everyone, welcome to Public Radio's travel show that takes you to the final frontier.

I'm Ad Kaplan. What is it that can't be seen but makes up most of

the universe? Doesn't shine or reflect but bends light. Resapes galaxies but whose composition is a mystery.

If you know the answer, there are a few thousand scientists who'd love to hear from you.

In the meantime, they learn what they can about dark matter

by mapping its distribution in distant realms of the

Cosmos. Richard Massey of Caltech was one of the first to use gravitational

lensing to create such maps. They'll join us to comment on the most recent

announcement about dark stuff made just a few days ago. Emily is here too.

Ms. Lochawala answers a question about the Magellan spacecraft, now settling into orbit around

Mercury in the most indirect fashion imaginable.

And Bruce Batts points out the bright lights above our heads in this week's what's up. He'll also reveal how many of those

lights are rocks that get uncomfortably close to our little planet. That

number will win a planetary radio t-shirt for another trivia contest entrant.

Speaking of trivia, what happened on May 21st, 1927?

That's right, it was 80 years ago that Charles Lindbergh made the first solo transatlantic flight.

And 80 years later to the day, Sophia was dedicated by his grandson Eric.

Sophia is the stratospheric observatory for infrared astronomy, a nearly 100 inch

telescope mounted in a 747 aircraft.

It will soon begin flying at 40,000 feet in higher, above 90% of the Earth's atmosphere,

and almost all infrared absorbing water vapor.

Stay tuned for images.

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