NASA is tracking the path of an asteroid as it flies past the Earth closer than the moon's orbit on Nov 8.
The asteroid, called 2005 YU55, measures around 1,300 feet across and will make its closest approach to Earth at 6:28 p.m. EST (11:28 pm GMT).
At its closest approach, the asteroid will pass within 201,700 miles (325,000 kilometers). Scientists will use this as an opportunity to learn more about the asteroid's chemical composition, surface features, shape and dimensions.
The average distance between Earth and the moon is 240,000 miles (386,242 km).
"The last time a space rock as big came as close to Earth was in 1976, although astronomers did not know about the flyby at the time," NASA say in a statement.
"The next known approach of an asteroid this large will be in 2028."
Due to its size and proximity, YU55 was classified as a "potentially hazardous asteroid" several years ago, but it poses no threat of hitting the planet, NASA says.
Although 2005 YU55 is in an orbit that regularly brings it to the vicinity of Earth, this next encounter will be closest it has has come for at least 200 years.
"This is the first time we've known about one this size in advance, due to the work of our NEO [near Earth object] program over the last 12 years," said Lindley Johnson, NASA's NEO Observations program executive in the agency's Planetary Science Division in Washington.
"Object 2005 YU55 was found in December 2005, so we've had almost six years of advance notice."
NASA will track the asteroid from Nov 4, using the Deep Space Network antenna. Radar observations from the Arecibo Planetary Radar Facility in Puerto Rico will begin Nov. 8.