A three-mile-wide asteroid is going to fly past our planet on Friday
Asteroid 1981 ET3 – also known as 3122 Florence – will fly past safely on September 1, 18 times further away than the moon. Named for Florence Nightingale, this asteroid is the biggest near-Earth object to pass this close since this category of objects was discovered over a century ago! It’s at least 2.7 miles (4.35 km) in diameter. It’ll safely pass by our planet on September 1, 2017 at over 18 times the Earth-moon distance.
Its size of about half the elevation of Mount Everest should allow it to reach a visual magnitude of +8.75 to +9, making it a relatively easy target for experienced observers at sites with dark skies. The cool thing is that the asteroid will certainly be visible in small telescopes and might even be visible in binoculars and for all sky enthusiasts should refer to the below picture to find Florence location:
Closest approach to Earth is expected to occur at about 8:06 am EDT on September 1, 2017, but backyard observers using a telescope can try to get a glimpse of the space rock a few nights before that date.
For all of us that don't have a telescope The Virtual Telescope Project will offer a live stream of the asteroid pass on August 31, 2017, beginning at 19:30 UTC:
https://www.virtualtelescope.eu/webtv/
Also Bareket Observatory in Israel will also host a webcast of this asteroid pass on September 1, 2017 beginning at 19:00 UTC:
http://www.bareket-astro.com/en/astronomical-webcasts/giant-asteroid-3122-florence-passes-earth-live-webcast.html