NASA’s first rover on Mars was a cute little bundle of robotic joy. Many thought it was likely to fail. Instead, Sojourner revolutionized how we explore Mars, and marked the start of 25 years of Mars rover adventures.

Episode one launches with Jennifer Trosper in the driver’s seat. As she looks in the rearview mirror at twenty-five years of exploring with NASA’s Mars rovers, she reveals how their progression has kept pace with milestones in her life.

In the fourth season of “On a Mission” we’ll be transported to the Red Planet with all five of NASA’s Mars rovers.

The Voyager 1 spacecraft has traveled farther away from Earth than any human-made object. Candy Hansen and David Grinspoon talk about the Voyager mission, and its humbling perspective of our planet as a tiny blue dot in the blackness of space.

We hike in the Australian Outback with Abigail Allwood to visit the most ancient fossils on Earth, and track the imprint of life over space and time with David Grinspoon.

From fires in outer space to raging wildfires on Earth, fire experts Gary Ruff and Natasha Stavros reveal how fingers of flame reach out around our world.

Get swept away as we fly into massive hurricanes, and hear how the rumblings of climate change will cause clouds to gather into ever more powerful storms.

As we fly around with NASA pilots, we’ll explore Earth’s air space with scientists Annmarie Eldering and Armin Sorooshian -- from wispy clouds high above, to tiny particles that make up air pollution.

Bundle up! We’ll be diving into ice-covered waters with an upside-down robot, and exploring Greenland’s massive ice sheet with oceanographer Josh Willis.

Dive to the deepest point of the ocean with an astronaut, brave the high seas with an oceanographer, and meander through sparkling rivers with a hydrologist.