We can never be too careful.
On July 20th Asteroid 2017 001 w came within 123,031 kilometers (or 76,448 miles) from Earth. The asteroid was approximately 37 to 77 meters (121 to 252 feet) across and was travelling at 6.4 miles per second at the time it passed our orbit.
And we didn’t spot it until July 23rd.
Thanks to the ATLAS-MLO telescope in Hawaii, data was uncovered that shows the near-miss.
If you compare this to other asteroids that have impacted our atmosphere, such as the the Chelyabinsk incident that exploded over russia in 2013, we see the significance of 2017 001 w. The meteor at Chelyabinsk was approximately 20 meters long (or 65 feet) and caused damage that included injuries to civilians and shattered glass across the region.
Below you can find a diagram that shows all near-earth asteroids larger than 1 kilometer (or 0.6 miles), these are the asteroids that could cause an extinction level event.
Thankfully Asteroid 2017 001 w made a safe pass, but it remains a present reminder that our asteroid detection technology can never be too advanced.