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The best time to spot Comet Lemmon is upon us. The bright green comet made its closest approach to Earth on Tuesday (October 21) - and it won't return for more than a thousand years.
The comet can mostly be found in the very distant outer Solar System, but its rare close approach to our home planet could give sky gazers the chance to see Comet Lemmon with the naked eye.
Comets are icy, dusty objects in space. As they move closer to the Sun in their orbits, the warmth of our star causes the ices on their surface to go from a solid to a gas, forming glowing tails as its dust scatters sunlight.
Comet Lemmon was only discovered in January this year at the Mount Lemmon Survey, in Arizona. It has been making its way towards Earth ever since - and this is the best week to see