Get your telescopes ready folks, because the night sky is slated to put on quite a show when the brilliantly green glowing remnants of a comet, cheekily nicknamed the “Incredible Hulk”, zips over the Northern Hemisphere on August 8.
First discovered in September 2017, PanSTARRS C/2017 S3 is an icy body falling toward the Sun from the outer Solar System’s Oort cloud. It began disintegrating as it got closer to the Sun this year, a process that was hastened by two dramatic explosions last month.
However, the massive dust cloud of its debris – estimated to be at least twice the size of Jupiter, the largest planet in our Solar System – remains on a trajectory that will bring it within 113.3 million kilometers (70.4 million miles) from Earth on Tuesday.
According to Popular Mechanics, the so-called Hulk’s remarkable hue is the result of cyanide and carbon molecules within the dust becoming ionized by solar winds. As the comet approaches the Sun, this effect is intensified, leading to a brighter glow; yet after this week, it will begin fading from our view. The celestial body’s perihelion – the point in its orbit that is closest to the Sun – is expected on August 16, at which time whatever remains of C/2017 S3 will be nearer to the Sun than Mercury. This event will be the first known instance of a comet passing through the inner Solar System.
Austrian comet expert Michael Jäger told Spaceweather.com that C/2017 S3 was initially expected to be visible with the naked eye when it flew by Earth, but that its subsequent breakdown has significantly dialed down its brightness.
"The comet is just a remnant of its former self. It is fading, becoming more diffuse and elongated each time I look," he said, noting that C/2017 S3 is now a 9th magnitude object – a classification that means it is still viewable with hobby telescopes and higher-powered binoculars.
Thankfully, if you miss the verdant display tonight due to cloudy skies or the lack of proper equipment, the perennial summer spectacular that is the Perseid meteor shower returns August 11-13. This year's display is expected to be particularly epic.
[H/T: The Weather Channel]