Watch 3-gigatonne asteroid Icarus make distant pass by Earth

As it passes by Earth at a distance of over 8 million kilometres, we are quite safe from "potentially-hazardous" asteroid 1566 Icarus. Courtesy: Celestia

Tuesday, June 16, 2015, 2:06 PM - Massive, "potentially-hazardous" asteroid 1566 Icarus is making its closest pass by Earth in nearly 50 years, and astronomers from the Slooh Observatory are tracking it with their telescopes!

Today, June 16, 2015, starting at 5 p.m. Eastern Time, the Slooh Community Observatory hosted a live internet broadcast featuring the flyby of Icarus - a "potentially-hazardous" asteroid, measuring around 1.4 km wide and tipping the scales at roughly 3 billion metric tons.

WATCH BELOW: Replay coverage of the Icarus flyby, presented by Slooh Host Eric Edelman, along with Slooh Astronomers Will Gater and Bob Berman, as they discuss this fascinating asteroid.

Although the perspective of the image above - viewing the flyby so as to include Earth and the Moon's orbit - perhaps does not accurately reflect the magnitude of scale of this flyby, the asteroid passes us at nearly 21 times the distance between the Earth ant the Moon.

Icarus (aka "1566 Icarus" aka "1949 MA"), which passes by the Earth at a distance of over 8 million kilometres today, is remarkable for a several reasons:

• Discovered in 1949 by German astronomer Walter Baade, the asteroid was named due to its orbit, which - like in the Greek myth - carries it very close to the Sun.
• An Apollo asteroid with an orbit that crosses Earth's orbit, Icarus is a "potentially-hazardous" asteroid (PHA), meaning that it sometimes comes within 7.5 million kilometres of Earth or closer.
• Today marks its closest pass since 1968, when it flew past at around 6.4 million km, and until the year 2090, when it will come within about 6.5 million km.
• These three passes - 1968, 2015 and 2090 - are its three closest approaches in the 300 years between 1901 and 2200.
• Icarus was the very first asteroid observed with radar, as astronomers bounced radio signals off of it as it flew past on June 14, 1968.
• This asteroid was the very first to be used in a planetary defense scenario, as a group of MIT graduate students developed "Project Icarus" in 1967, to explore the potential to deflect this massive asteroid with rockets, should it be headed straight for Earth.
• Project Icarus became the basis of the science fiction feature film Meteor, which showed for the first time in 1979.

Fortunately, the possibility of Icarus striking the Earth remains in the realm of science fiction.

"We’re perfectly safe of course," said Slooh astronomer Will Gater, "but close approaches like this one are always a reminder that our Solar System is a dynamic place, and that asteroids are thought to have played an important role in our past."

If you missed the live show, restart the video above for a replay of the event, and comment via social media with the #IcarusCloseUp hashtag!

Sources: Slooh | NASA JPL | NASA JPL News