Monolito 2001 -

It had been three days since the excavation team on the moon—funded by a silent coalition of space agencies—unearthed the impossible object from a crater floor. The Tycho Monolith, they called it. Blacker than any black, smooth as a frozen lake, and precisely four meters tall, two wide, one deep. Its edges were sharper than a scalpel's blade. It had been buried for four million years.

In the original short story by Arthur C. Clarke, The Sentinel , the object was a glittering pyramid. However, Kubrick opted for the minimalist rectangular slab to evoke a sense of uncanny perfection. The dimensions of the Monolith are famously set in a ratio of monolito 2001

When active, the Monolith emits a low-frequency vibration (sub-bass) that resonates in the human chest cavity. It is the sound of the background radiation of the universe, organized into a rhythmic, mathematical pulse—effectively the "heartbeat" of the galaxy. It had been three days since the excavation

She wrote it on the walls of every classroom, every council chamber, every launchpad: Its edges were sharper than a scalpel's blade

The Monolith appears at four pivotal moments in the film, acting as a catalyst for "evolutionary leaps":