Comet Pan-STARRS (C/2011 L4) is now inside the orbit of Mercury and it is brightening as it approaches the sun. Observers in the southern hemisphere say the comet can be seen with the naked eye even through city lights. Currently, it is about as bright as the stars of the Big Dipper (magnitude +2 to +3). The comet could become even brighter when it moves into northern hemisphere skies in the second week of March. Checkhttp://spaceweather.com for current images and updates.