# Mariner 10: First to Mercury and Venus

# Astronomy Tonight Podcast This is your Astronomy Tonight podcast. Welcome back, stargazers! Today we're celebrating one of the most triumphant moments in the history of space exploration that occurred on June 9th, and I have to tell you—this one still gives me goosebumps. On June 9, 1974, the Mariner 10 spacecraft made history by becoming the **first spacecraft to visit Mercury**, our solar system's scorching little speedster. But here's where it gets really exciting: this wasn't just a casual flyby. Mariner 10 had already visited Venus just months earlier, making it the first spacecraft ever to visit *two* planets in a single mission. Talk about an overachiever! Picture this: Mercury, a world we knew almost nothing about, suddenly revealed in stunning detail. Mariner 10 sent back the first close-up images of Mercury's cratered surface, showing us a world that looked remarkably similar to our Moon. The spacecraft discovered that Mercury had a magnetic field—completely unexpected for such a small planet. Scientists were blown away! It also revealed that Mercury's surface temperature swings from a blistering 430 degrees Celsius on the sun-facing side to a frigid -180 degrees on the dark side. That's a temperature range that would make any planet jealous. And Mariner 10 didn't stop there. It went on to make THREE flybys of Mercury before mission control finally said goodbye in 1975. The little probe that could became a legend. So make sure to **subscribe to the Astronomy Tonight podcast** so you never miss these incredible cosmic stories! If you want more information about today's astronomy event or any of our episodes, head over to **quietplease.ai**. Thank you for listening to another Quiet Please production!