NASA’s New Horizons spots signs of liquid nitrogen flowing on Pluto

Scientists have found the first evidence that liquid may have flowed across Pluto’s surface in the recent past. Dark features on the enormous Sputnik Planitia glacier appear consistent with liquid nitrogen rising through cracks from deep beneath the ice. Computer models show that nitrogen could melt at the glacier’s base and travel upward like fluid through small conduits. The finding reveals that Pluto may be much more geologically active than its frozen appearance suggests.