# Arecibo's Message: Humanity's Letter to the Stars
Published: January 15, 2026
Duration: 1:42
# This is your Astronomy Tonight podcast.
Good evening, stargazers! Today we're celebrating a truly cosmic milestone that occurred on January 15th, and boy, do we have a story for you!
On January 15, 1974, the legendary astronomer **Carl Sagan** and his colleagues sent humanity's first deliberate message to extraterrestrial intelligence into space. But this wasn't just any message – it was beamed from the Arecibo Observatory in Puerto Rico using the most powerful transmitter available at the time, pointed straight at the globular star cluster M13, about 25,000 light-years away.
The message itself was a masterpiece of cosmic di...
Good evening, stargazers! Today we're celebrating a truly cosmic milestone that occurred on January 15th, and boy, do we have a story for you!
On January 15, 1974, the legendary astronomer **Carl Sagan** and his colleagues sent humanity's first deliberate message to extraterrestrial intelligence into space. But this wasn't just any message – it was beamed from the Arecibo Observatory in Puerto Rico using the most powerful transmitter available at the time, pointed straight at the globular star cluster M13, about 25,000 light-years away.
The message itself was a masterpiece of cosmic di...