Today is the first day that we in Maine may see Comet Panstarrs 2011L4. The Sun sets at 5:38pm. The comet will be where the Sun was, skimming the horizon until it, too, sets at 6:33pm. You’ll need a good vantage point with a clear view, but with any luck, the comet will be visible to the naked eye. Bring optics just in case; they will certainly help in the time before darkness.
Google “Panstarrs 2011L4” for more information. Or, here’s a quick link to Wikipedia.