Image credits: NASA/JHUAPL/SwRI.NASA’s New Horizons spacecraft spied several features on Pluto that offer evidence of a time millions or billions of years ago when — thanks to much higher pressure in Pluto’s atmosphere and warmer conditions on the surface — liquids might have flowed across and pooled on the surface of the distant world. “In addition to this possible former lake, we also see evidence of channels that may also have carried liquids in Pluto’s past,” said Alan Stern, Southwest Research Institute, Boulder, Colorado—principal investigator of New Horizons and lead author of the scientific paper.
This feature appears to be a frozen, former lake of liquid nitrogen, located in a mountain range just north of Pluto’s informally named Sputnik Planum. Captured by the New Horizons’ Long Range Reconnaissance Imager (LORRI) as the spacecraft flew past Pluto on 14 July 2015, the image shows details as small as about 430 feet (130 metres). At its widest point the possible lake appears to be about 20 miles (30 kilometres) across.
Ceres, the largest minor planet inside the orbit of Neptune, passed closest to Earth on the evening of 22 October — the night of the last quarter Moon. With the lunar crescent now confined to the morning sky, grab your binoculars or telescope, print out some star charts from our online guide and track down the brightest of the dwarf planets while at its best.
NASA’s New Horizons probe, three years outbound from Pluto, has woken from electronic hibernation, healthy and on course for a New Year’s Day flyby of an even more remote Kuiper Belt object nicknamed Ultima Thule.
Astronomers searching the outer solar system for signs of a super Earth-size world beyond Pluto have found another small body in an orbit consistent with the presumed gravitational influence of the presumed Planet X.
