The reason Asteroid Day falls on this date is because it’s the anniversary of the 1908 “Tunguska event” when scientists believe a 50 meter wide asteroid exploded over Siberia (see Earth Sky, Wikipedia).
In honor of Asteroid Day, the Science Channel posted this great 360° Video.
Here’s another interesting 360° Video that Scott Manley posted a few years ago in which he models the asteroids near the Earth, calculates their positions and places them on a virtual Sky sphere.
Of course, the real point of Asteroid Day is to remind people of the danger of earth being hit by Near-Earth Objects (see NASA, Wikipedia). If you are curious, here is a list of the known Potentially Hazardous Asteroids which is funded by NASA and maintained by the Minor Planet Center hosted by the Smithsonian Astrophysical Observatory (part of the Harvard-Smithsonian Center for Astrophysics).
Our understanding of the risk is actually an ever changing and moving target. For example, just last week news broke of a new and unexpected source of potentially dangerous asteroids hiding in the Taurid Meteor shower.
Massive asteroids in popular meteor shower pose major threat (Eric Mack, CNET)
If you are interested in learning a lot more about asteroids and what we may be able to do to protect ourselves, there is going to be an international a 24-hour Asteroid Day program from Broadcasting Center Europe, beginning at 1 am on June 30 (GMT).
Here are NASA’s and JPL’s Press Releases about the event.
NASA Celebrates International Asteroid Day with Special Broadcast (NASA Press Release)
NASA Celebrates International Asteroid Day with Special Broadcast (JPL Press Release)
You can watch the live stream here:
Asteroid Day Live Stream
Here are a few more articles articles published in honor of this year’s Asteroid Day.
Are asteroids leaving the spotlight? No way, say Asteroid Day activists (Chelsey Ballarte & Alan Boyle)
Could Asteroids Bombard the Earth to Cause a Mass Extinction in 10 Million Years? (Sanna Alwmark, Matthias Meier, Scientific American)
Find out more about asteroids…