Mark Raymond on the dawn mission this week on planetary radio.

Welcome to the travel show that takes you to the final frontier. I'm

at the Planetary Society. Dawn's chief engineer and mission director returns

with news that the ion-engine-driven spacecraft is now closer to dwarf

planet series than ever. Mark will share the latest science. Commercial space

access reached two more milestones in the last few days.

We'll talk about them with Bill Nye.

And we're giving away one of the coolest prizes ever in What's Up Space Trivia Contest with Bruce Betts?

Emily Lochuwala is the Planetary Society's senior editor.

Emily, there is more news from Cassini this week.

Tell us why it is bittersweet.

Well, we got up toward the end of 2015, the beginning of this year some really wonderful icy

moon images from Cassini. And of course I've always loved processing these pictures.

Writing about Cassini is the first kind of science writing I did for the planetary

society. But it's bittersweet because Cassini just flew past Titan which it does a lot

but this particular Titan flyby tilted the orbit up and out of the

ring plane. And Cassini has to be in the orbit of the ring plane for frequent moon encounters.

This marked the very last time that Cassini will ever be in a ring plane orbit from now until the very end of the mission.

It's going to be diving up and below the rings.

And of course, that isn't a terrible thing.

Cassini will be getting fantastic views of the rings from here

on to the end of the mission, but this is pretty much it for dense moon

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