Antarctica’s Onyx River

The Onyx is a seasonal meltwater stream in the McMurdo Dry Valleys, flowing from Lake Brownworth to Lake Vanda. Sources give its length as roughly 28–32 km, rather than about 40 km. Microorganisms, including cyanobacteria and algae, live in the water and rocky streambed; there are no fish. In some years, flow does not reach the lake.