Mercury-bound spacecraft whizzes past the smallest planet for the 2nd time

All five naked-eye planets will appear lined up (in order) in the morning sky tomorrow (Friday, June 24). The last time this rare planetary alignment occurred was way back in 2004. And it won't happen again for nearly 20 years.

This is the best time to spot a rare alignment of five planets. Here's how to watch it.

For the first time, a small rocket will launch a private spacecraft to the Moon