Ashley Dove-Jay: "Both solutions are promising. Both have significant financial support. But which approach is more economically sound? Will one solution render the other obsolete? Using the best information available, with support from BBC Sky at Night Magazine, I’ve tackled this question."
The supermassive black hole is 40 million times as massive as the sun and powers a quasar that existed 700 million years after the Big Bang.
The asteroid zoomed by Earth at a perfectly safe distance of around 1.8 million miles (2.9 kilometers).
Images show surprise changes to the spacecraft as it interacted with the atmosphere.
Spaceplanes sound cool!