Fields of sea ice melt in northeastern Canada’s Hudson Bay in this true-color Aqua MODIS image acquired on July 5, 2003. During the winter, sea ice accumulates to the point where the ice is so thick that it prohibits the passage of all but the sturdiest of ice-breaking ships, and oftentimes prohibits even them. But as the spring and summer seasons heat the water and air, the ice melts and breaks up, leaving what looks like slush on the water surface. The Bay is generally ice-free and navigable from mid-July to October.
In fact, what looks like slush in this image could well be huge ice floes; MODIS flies at an altitude of 705 kilometers, and this perspective can make large objects appear quite small. Hudson Bay is a huge body of water; it covers 1,230,000 square kilometers (about 475,000 sq mi), is almost 1,400 kilometers long and over 1,000 kilometers wide. Almost all of Texas, Oklahoma, New Mexico, and Mississippi cover as much area as Hudson Bay, which is actually an inland sea.