How to See The Biggest Asteroid to Pass Earth Since Records Began

Amateur astronomers have the chance to spot a huge asteroid flying past Earth over the next few days — all from their own backyards.

Asteroid Florence is quite big as far as asteroids go: at 2.7 miles across, it’s the biggest to pass earth since NASA started keeping records, according to the space agency.

“While many known asteroids have passed by closer to Earth than Florence will on September 1, all of those were estimated to be smaller,” Paul Chodas, manager of NASA’s Center for Near-Earth Object Studies, said in a statement.

It will cruise by at a safe distance of 4.4 million miles or about 18 times the distance between the earth and the moon, NASA said. This is the closest that Florence has been since 1890 on its travels through the solar system, according to the agency, and will not come this close again until after the year 2500.

The asteroid, which can be seen using a small telescope, will appear as bright as a 9th-magnitude star because its large surface means that it reflects almost twice as much light from the sun as the moon, according to Sky & Telescope.

The best moment to see the asteroid from the U.S. will be 8 p.m. EDT on Saturday, according to S&T, as this is when the asteroid will pass much dimmer stars.

S&T has made four detailed charts that show how the asteroid will be moving south to north through the Capricornus, Aquarius, Delphinus, Vulpecula, and Cygnus constellations.