Q&A with Scott Bolton, principal investigator on NASA’s Juno mission

After a six-month voyage from Earth, NASA’s InSight Mars lander, streaking through space at at some 12,300 mph, will slam into the thin martian atmosphere Monday afternoon to begin a nail-biting six-and-a-half-minute descent to the surface, kicking off a billion-dollar mission to probe the red planet’s hidden interior.

Five years after a balky valve kept it from entering orbit around Venus, Japan’s Akatsuki space probe is again approaching the sweltering planet for another shot at completing its science mission in December, officials said Friday.

After the threat of lightning kept the mission on the ground Thursday, Arianespace and the European Space Agency successfully launched an Ariane 5 rocket Friday from Kourou, French Guiana, with the Jupiter Icy Moons Explorer mission, a robotic spacecraft embarking on an eight-year journey to the solar system’s largest planet. Liftoff with ESA’s JUICE spacecraft occurred at 8:14 a.m. EDT (1214 UTC).