For the first time in my life, I looked up at the night sky last night and saw the Triangulum Galaxy with my naked eye.
This might not seem like a big deal for most people, but it really is; At 3 million light years away Triangulum, or Messier 33, is one of the most distant permanent objects that can be seen without the aid of a telescope. As a diffuse object, M33 is incredibly difficult to see if you’ve got even a little bit of light pollution and being able to eyeball it without having to use averted vision is one of the benchmarks of the Bortle Dark-Sky Scale, the quick-and-easy way to determine if you can look up at the sky and see the entire cosmos or just a handful of stars.
The Bortle Scale is great for determining exactly what you can expect to see in the night sky. Created by John Bortle in 2001, it features an easy-to-understand scale ranging from 1 to 9, with lower numbers better for night viewing. It’s nearly impossible to find a 1 on the Bortle Scale nowadays unless you’re perched atop a glacier somewhere in Alaska; most you can really hope for is somewhere between 2 and 4, thanks to the amount of light pollution we all have to live with due to urban sprawl.
Growing up on Long Island less than 50 miles away from New York City meant that most of the night sky I saw was pretty washed out. Sure, I could make out constellations like Orion, Cassiopeia, and the Big and Little Dippers, but that was about it – otherwise the sky was devoid of any sort of detail. I remember being floored at how full the sky looked when I went away to school at New Paltz; it wasn’t until then that I actually saw something resembling the Milky Way. Still, even that experience pales in comparison to where we are now.
You remember that scene at the end of 2001: A Space Odyssey? You know, where Dave Bowman touches the Monolith and says, “My God, it’s full of stars?” Yeah, it’s kind of like that. We’ve got to be around a 4 or a 3 on the Bortle Scale, which is pretty damn good for being within 25 miles of a major population center like Lake George. It’s certainly the clearest sky I’ve ever seen in my entire life. I can’t even imagine what a 2 or a 1 would look like. Probably terrifying.