Largest known near-Earth asteroid set to whizz past us in September

18 Aug 2017

A near-Earth asteroid (not Florence) passes Earth. Image: Flashinmirror/Shutterstock

Our planet is to be reminded just how vulnerable it is with the largest near-Earth asteroid ever detected due to pass us by quite soon.

For the past few years, with Asteroid Day, the world has been made aware of the potential catastrophe that could be brought on by a large asteroid finding itself on a collision course with Earth, something that has happened more than once.

Now we are getting a visual reminder, as NASA has revealed that we are soon to be passed by an enormous asteroid called Florence, named in honour of the most famous of nurses, Florence Nightingale, when it was discovered in 1981.

Future Human

Expected to pass by without incident on 1 September, Florence is among the largest near-Earth asteroids, with readings from the space debris putting its size at about 4.4km. It will fly past at a distance of 7m km from Earth.


Good opportunity for astronomers

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

“Florence is the largest asteroid to pass by our planet this close since the NASA programme to detect and track near-Earth asteroids began.”

While it might not be threatening the safety of our planet, NASA does plan to make the most of this opportunity, with the space agency’s ground-based radar set to track the flyby in the hopes of understanding more about it.

The next opportunity that astronomers would have to observe it from such a close distance on Earth won’t come again until after the year 2500.

The resulting radar images will show the real size of Florence and also could reveal surface details as small as about 10 metres, NASA said.

For any amateur astronomers out there, Florence will brighten to ninth magnitude in late August and early September, when it will be visible in small telescopes for several nights as it moves through the constellations Piscis Austrinus, Capricornus, Aquarius and Delphinus.

Colm Gorey was a senior journalist with Silicon Republic