by Two skyscraper-sized asteroids are zooming toward Earth this weekend, with one making its closest approach on Friday (July 29) and the other whizzing past on Saturday (July 30).
The first asteroidcalled 2016 CZ31, will fly by around 19:00 ET (23:00 GMT) on Friday, hurtling at an estimated 34,560 mph (55,618 km/h, according to NASA.
Astronomers estimate that the asteroid measures about 400 feet (122 meters) at its widest point, making it about as wide as a 40-story building is tall. The asteroid will safely miss our planet, passing approximately 1,740,000 miles (2,800,000 kilometers) from Earth — or more than seven times the average distance between the Earth and moon. According to NASA, this spacecraft approaches Earth every few years, with the next one scheduled for January 2028.
Related: Why are asteroids and comets such strange shapes?
On Saturday, a second, increasingly large asteroid will skim past our planet, albeit at a greater distance from Earth. That asteroid, called 2013 CU83, measures about 600 feet (183 m) at its widest visible point, and will pass about 4,320,000 miles (6,960,000 km) from Earth, or about 18 times the average distance between Earth and the moon.
This colossal space rock will travel at 13,153 mph (21,168 km/h) when it approaches Earth at 7:37 PM ET (11:37 PM GMT).
Both of these close encounters are significantly further away than asteroid 2022 NFwhich came within 56,000 miles (90,000 km)—or about 23% of the average distance between the Earth and the Moon—on July 7.
NASA and other space agencies closely monitor thousands of near-Earth objects like these. Even if an asteroid’s orbit puts it millions of miles from our planet, there is an extremely small chance that the asteroid’s orbit could change slightly after interacting with gravity of a larger object, such as a planet; even such a small shift could potentially put an asteroid on a collision course with Earth on a future flyby.
As such, space agencies take planetary defense very seriously. In November 2021, NASA launched an asteroid-deflecting spacecraft called the Double Asteroid Redirection Test (DART), which will slam directly into the 525-foot-wide (160 m) asteroid Dimorphos in autumn 2022. The collision will not destroy the asteroid, but it might change the space probe’s trajectory a little, Live Science previously reported. The mission will help test the viability of asteroid deflection, should a future asteroid pose an imminent danger to our planet.
Originally published on Live Science.
