The answer: Happy Birthday.
The question: What was the first song ever played on the planet?
That doesn’t seem possible. The song “Happy Birthday” only dates back to about 1893, and even then, it had different lyrics. The Earth, putting aside some existential arguments about reality etc., definitely existed in 1892, and there are plenty of famous musicians who were long-dead by the time Happy Birthday first graced the ears of those in its first audience.
But the question and answer above are correct, as far as we know. The trick?
The planet is Mars.
On August 5, 2012 (in the U.S., at least), NASA’s Curiosity rover landed on Mars. The rover’s ongoing mission on the alien planet is one of exploration, gathering data about Mars’ climate and geology. Because Curiosity’s voyage to Mars is intended to be a one-way trip — we don’t yet have a way to launch interplanetary shuttles from Mars to Earth — the rover acts as a mobile laboratory, able to perform varied experiments while on the Mars surface. Some of those experiments require geological samples, so Curiosity needs a way to collect the samples and then move them into the lab areas of its confines.
To do this, Curiosity is outfitted with a group of instruments known collectively as SAM, which stands for “Sample Analysis at Mars.” The SAM team, from Earth, instructs the rover to create a series of vibrations which manipulate the positioning of Curiosity’s collection devices. In turn, those devices — now moving at NASA’s command — collect samples from the surface and move the dirt into the analysis area of the device. As a side effect, like any other vibrations, the ones sent from the Earth to Mars result in a series of harmonics. Typically, the sounds are ear-jarring ones which could hardly be considered music. But August 5, 2013 was a special day.
On that day, as seen above, the SAM team sent a sequence of vibrations consisting of carefully planned peaks and valleys. Those vibrations weren’t intended to collect samples from the Mars surface. They were sent to mark the fact that Curiosity had landed there a year prior — in song. If you care to listen, that’s a screenshot from a NASA video available here, and you’ll immediately recognize the tune as that from Happy Birthday.
So unless an advanced civilization lived on Mars long ago, or unless Elvis truly isn’t dead and instead relocated to a place a little further from the Sun, Happy Birthday was the first song ever played on the planet Mars.
From the Archives: Happy Birthday (c): Why the Curiosity rover may have violated someone’s copyright (if such things apply on Mars).
Take the Quiz: Name these words that start with “MAR.”
Related: A Hot Wheels version of the Curiosity rover. It probably doesn’t play Happy Birthday but it’s pretty cool anyway.