望住天空: NASA繃緊準備這週末三顆巨大的小行星掠過地球

望住天空: NASA繃緊準備這週末三顆巨大的小行星掠過地球
Keep Your Eye On The Sky: NASA Braces For Three Huge Asteroids To Skim The Earth This Weekend

Is it good or bad things that come in threes? We'll find out soon enough: according to data from NASA's Center for Near Earth Object Studies, there are at least three asteroids set to make close approaches to Earth this weekend, one of which has an estimated diameter between 14 and 30 meters (100 feet) wide – up to the size of a London bus.

The first of the set – 2018 VA2 – is due to zip by on Friday, with the others not far behind. It is estimated between 32 and 75 feet wide, has an approach distance around 446,000 miles, and is moving at a velocity of .6 miles per second relative to Earth. 2018 VR1 is the big daddy of the bunch, but it is estimated to have the furthest approach distance at around 3.1 million miles. Luckily, none of the other asteroids pose a threat of impact because of their trajectories – but NASA still classifies their approaches as "close." (Better safe than smashed.)

To you sky-watchers out there, unless you have a satellite handy, don't bother gazing upwards for any of the asteroids – they're just too small and too far away. That being said, the CNEOS near approach chart currently has 17 entries that will last us through January 4, 2019, so maybe there will be other opportunities for you to break out the 'scopes and lenses in the near future.

https://www.outerplaces.com/science/item/19049-nasa-three-asteroids-weekend