Since August, Mars has been drifting farther away from us and getting dimmer in our sky as Earth pulls ahead of it in our course around the Sun. But a large, regional dust storm has popped up on the planet, causing Mars to brighten slightly again. The storm was first reported to the International Astronomical Union (IAU) on December 13 by planetary observer Don Parker of Florida. According to IAU Circular 8256, issued on Sunday morning, the dust storm appeared to extend over 3,000 kilometers (over 1,800 miles) of longitude (in the east-west direction) and about 1,800 km (over 1,100 miles) in latitude (in the north-south direction). It covered most of Chryse Planitia (a low-elevation plain where Viking 1 landed), extending west into Candor Chasma and south into Eos Chasma and Margaritifer Sinus. On Sunday, observations by Parker revealed that the cloud seemed to be spreading even farther south and into Argyre Planitia.