2,000 Comet Collisions Happen Every Day in the Fomalhaut System
Written by Colin Devroe · 19 February 2015
Every now and then the human family holds their collective breath as an asteroid whizzes by Earth in what, in astrological terms, could be called a near miss. A near miss is whenever a large space object comes within a few distances of the moon’s orbit; or roughly 250,000-750,000 miles from the top of your head. Some, like 2014 DX110, have even come within the moon’s orbit.
Most recently 2004 BL86 came within a few times the distance of the moon and zinged by while we all carried on with our daily lives; eating, drinking, complaining on Twitter. You likely didn’t even hear about it. (Side note: Isn’t it cool that 2004 BL86 has a moon?)
GIF below: 2004 BL86 and its cute little moon. Credit NASA/JPL-Caltech.
It is fairly rare, though, that these same pieces of space junk — of which there are literally millions flying around within our solar system — collide together in any way that we take much notice. While there are bits of junk bumping into each other every moment of every day out there we don’t really pay much attention.
There have been times, though, when we have taken noticed of stuff smashing into each other. You may remember our bit here about the closely observed surface of Mars and its impact craters. I also think back to when I saw Shoemaker Levy 9 striking into Jupiter’s surface. The images may not look all that spectacular but, man oh man, the numbers are staggering.
Image left: Pieces of Shoemaker Levy 9 barreling towards Jupiter like the projectiles from a Tommy Gun. Image right: The impacts as they collided with the gas giant’s surface appear to wrap around as Jupiter spins. Credit: JPL/Monde.
It is estimated that the energy from this repeated impact on the Jovian surface raised the temperature of the atmosphere at the impact sites to roughly 42,000 degrees fahrenheit. It is incredibly difficult to even try to get any perspective on that type of energy output.
The Fomalhaut System
There is a solar system in our Milky Way, about 25.1 lightyears from our own, that has an incredible show happening every single day. One that would make Shoemaker Levy 9 colliding with Jupiter look like a pillow fight.
Every single day there are 2,000 comet collisions in the Fomalhaut system.
2,000 Comets. Colliding. Every. Single. Day.
We’ve seen our fair share of comets from here on Earth. Even in my lifetime. Just this past month I thoroughly enjoyed observing Comet Lovejoy (C/2014 Q2) on each clear night. Especially while I was in Mexico where I was able to see it really clearly. But we’ve never seen anything on the scale of what is commonplace in the Fomalhaut system.
Most comets have a core at least 6 miles across. In other words, they are pretty big. And they are moving really, really fast. Lovejoy is moving at roughly 85,000 miles an hour as I write this.
Imagine a bulbous ball of ice, rock, and metal that stretches at least 6 miles across moving at 85,000 miles an hour smashing into another bulbous ball of ice, rock and metal traveling at similar speeds. It would create an explosion that, if it were to happen in our atmosphere, would do some serious damage to our planet. Now, imagine this happening 2,000 times a day every day for millennia.
To gain some perspective on this, watch this orbit simulation video from the perspective of Fomalhaut b, an exoplanet that was somewhat recently discovered in the Fomalhaut system that has, what could easily be called, the best seat in town for this comet-sized pinball show.
I’ll be 35 this year. Since my first breath there have been more than 25,550,000 comet collisions that have happened in the Fomalhaut system. And today, if we were to observe this system through a remarkably good telescope, we’d be seeing this enormously destructive comet show play out as it happened from the year 1990 or so. (Because that is how long light takes to get here.)
To flip this around, however, the Fomalhaut system is about to start receiving some of the best rap music that Earth has ever produced. But I digress.
We’re pretty fortunate to be living in a solar system that is relatively quiet, calm, and even peaceful rather than in a system that leaves an imprint on the back of our eyelids similar to what Bilbo Baggins sees every time he closes his eyes.