Right now, the Mars rover Curiosity is trudging through the dusty terrain of the red planet, where it’s been hard at work for over ten years. Among its many onboard devices, the car-sized robot has a machine on its belly called the “sample-analysis unit.” Curiosity uses its mechanical arm to put soil in the sample-analysis unit, which then vibrates at different frequencies to sort the dirt into different little cups. Then the cups heat up to release gasses, which are studied in different ways.
2013 marked the first anniversary of Curiosity’s arrival on Mars, and the scientists at NASA thought of another way to use the sample-analysis unit. They programmed it to vibrate out a little tune. There, all alone on a planet 236.6 million miles from home, Curiosity sang happy birthday to itself.
Curiosity has had ten birthdays since then, but the power used up for singing is a limited resource. NASA only let Curiosity sing to itself that one time. On a less tragic note, robot lawnmower company Husqvarna had a fleet of its machines use their alarm systems to sing happy birthday to Curiosity in 2022, celebrating the rover’s big ten.