When a team of scientists have launched a space probe to the heart of our solar system in brand-new mission to our Sun, it makes fresh discoveries reveal how it works; along the way, experts uncover a surprise find on Mercury.
| Name | Type | Role | |
|---|---|---|---|
| Eugene Parker | Guest Star | ||
| Nicola Fox | Guest Star | ||
| Suzanne Imber | Guest Star | ||
| Sten Odenwald | Guest Star | ||
| James Slavin | Guest Star | ||
| Lucie Green | Guest Star | ||
| James Green | Guest Star | NASA Chief Scientist | |
| Matthew Genge | Guest Star |