New Horizons’ historic flyby of Pluto revealed a world far more complex and dynamic than expected. The spacecraft’s observations of the dwarf planet’s surface, atmosphere, and geological features showed signs of recent activity, including possible ice volcanoes, flowing nitrogen ice, and an atmosphere that is not as thin as initially thought.
The most surprising discovery was Sputnik Planitia, a region of smooth, crater-free plains that suggests Pluto has undergone significant resurfacing in the recent past. This finding contradicts the initial expectation of a heavily cratered surface, indicating that Pluto’s surface may be more youthful than previously believed.
New Horizons also provided evidence of nitrogen-rich ice moving around obstacles, filling basins, and behaving like a dynamic landscape. This phenomenon is unlike anything seen on Earth, where nitrogen is primarily thought of as a gas in the air.
The flyby revealed that energy and change do not require the warmth of Earth to shape a world’s surface. Weak sunlight, volatile ices, internal heat, seasonal cycles, and long-term orbital effects can still produce surfaces that look young and active.
While some claims, such as possible cryovolcanism, are still subject to interpretation, the overall picture presented by New Horizons is one of Pluto as a complex, dynamic world with an atmosphere and geological features that defy our initial expectations. The flyby has significantly changed our understanding of Pluto, showing that the outer Solar System can harbor surprising complexity in places once thought too cold to be interesting.
Source: https://spacedaily.com/t-scientists-expected-pluto-to-be-a-frozen-ancient-world-scarred-by-billions-of-years-of-impacts-but-when-new-horizons-finally-arrived-in-2015-it-found-something-stranger-smooth-young-plains-with-al