Astronomers Snap Images of Near-Earth Asteroid 2019 OK | Astronomy – Sci-News.com
Using several telescopes of the International Scientific Optical Network (ISON), astronomers have captured a series of images of the recently-discovered near-Earth asteroid 2019 OK.
The 330-foot- (100 m) wide asteroid 2019 OK passed just 43,500 miles (70,000 km) from Earth on July 25, 2019.
The object was discovered by the Southern Observatory for Near-Earth Asteroids Research (SONEAR) just a day before its close approach.
Observations of 2019 OK were independently confirmed by other observatories, including the Arecibo radar in Puerto Rico and the ISON network.
Since the discovery, with knowledge of where the asteroid would have been and by searching for it by eye, existing images were found in the Pan-STARRS and ATLAS sky survey archives.
Both surveys had in fact captured the asteroid in the weeks before the flyby, but this slow space rock appeared to move just a tiny amount between images, and was therefore not recognized.
With these observations, asteroid experts were able to extract precise measurements of the position and movement of 2019 OK.
“With the ISON observations we were able to determine the distance of the close approach incredibly accurately,” said Dr. Marco Micheli, an astronomer with ESA’s Near-Earth Object Coordination Centre.
“In fact, with a combination of observations from across the globe, the distance is now known to better than one kilometer.”
2019 OK travels in a highly elliptical orbit, taking it from within the orbit of Venus to well beyond that of Mars. This means the time it spends near Earth and is detectable with current telescope capabilities is relatively short.
Asteroids the size of 2019 OK size are relatively common in the Solar System, but hit Earth on average only every 100,000 years.
Traveling in a highly elliptical orbit that takes it within the orbit of Venus, this asteroid wont come close to Earth again for at least 200 years.