The interplanetary interloper won’t come closer than 1.25 million miles to Earth, but it will present a valuable scientific opportunity for astronomers.

The largest asteroid predicted to pass by our planet in 2021 will be at its closest on March 21, providing astronomers a rare opportunity to get a good look at a rocky relic that formed at the dawn of our solar system.

Called 2001 FO32, the near-Earth asteroid will make its closest approach at a distance of about 1.25 million miles (2 million kilometers) – or 5 1/4 times the distance from Earth to the Moon. There is no threat of a collision with our planet now or for centuries to come.

The latest hypothesis that the demise of the dinosaurs was precipitated by a cometary fragment that slammed into the Gulf of Mexico some 66 million years ago is being met with skepticism in the Earth sciences community.

A fragment of a large, long-period comet was most likely responsible for the impactor that killed off the dinosaurs.