Brightening a millionfold since its discovery in June 2011, the icy interloper has already become easily visible by the naked eye from the Southern Hemisphere as a distinct tail of gas and dust. (Related: "New Comet Found; May Be Visible From Earth in 2013.")
Astronomers originally stumbled upon the comet nearly two years ago while searching for potentially hazardous asteroids. Using one of the world's largest digital cameras, on Hawaii's Pan-STARRS telescope—the comet's namesake—the team snagged a faint image of the comet while it was still more than 700 million miles (1.1 billion kilometers) away, between the orbits of Jupiter and Saturn.
What gave it away was its fuzzy appearance, which is caused by the melting ice and released gases forming a hazy shell around the comet's nucleus.
In the past few weeks the comet has made its way into the inner solar system, and it will reach perihelion—its closest approach to the sun—at a distance of 30 million miles (48 million kilometers) from the sun on March 10. (Video: Sun 101.)
There's no chance of collision with Earth however, as the body has already gotten as close it will get to our planet, at about 100 million miles (160 million kilometers) away.