Explode into space
Against the inky blackness of space, anything lit up by the Sun can be seen at vast distances. I’ve watched objects in Earth orbit the size of a phone booth become the brightest light in the sky from 1000 miles away.
So on October 23rd, when a distant and obscure comet half way between Mars and Jupiter shed an amount of ice and dust roughly a fifth of the amount of material spewed out by Mount Saint Helens in its 1980 eruption, people noticed very quickly. What had been too dim to see in even large amateur scopes became a naked eye object in a few hours.
I first saw it two days into the outburst; it was the tail end of the week when Southern California was on fire, and I couldn’t even see the surrounding constellations to guide me to where it was. But a few seconds of scanning with binoculars and it popped right out; unlike anything I’d ever seen before, it was an obvious disk against the hazy sky. Day by day, it’s been growing and changing, slowly moving across Perseus. It’s becoming less obvious to the naked eye as it expands to the size of the Sun, but it’s still visible even from urban locations like mine.
Watching the sky is an endeavor that mixes the incredibly predictable with the utterly unexpected. I love it when something like Comet Holmes comes along.