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Showing posts from January, 2015

Feeling the Love and Joy

Comet Lovejoy has been gracing the night skies for several months. As it travels north-ish across the background of stars, it's been getting higher in the sky for us in the northern hemisphere. It also recently completed perihelion (the point in its orbit when it's closest to the Sun) and its closest approach to Earth. These have all come together to make a pretty impressive showing for this comet discovered just last year.

As comets get closer to rounding the Sun, they typically get brighter. That's because the Sun heats up the comet's body, causing material on the comet to sublimate, which produces gas vents and loosens debris. The gas and other material fly off the comet body, which is what makes a comet "fuzzy" and usually produces a noticeable tail.

It's often mistakenly believed that a comet's tail indicates its direction of travel. When airplanes leave contrails or rockets take off leaving a stream of exhaust, we naturally understand that the t…