The gas composition of a planet's atmosphere generally determines how much heat gets trapped in the atmosphere. For the dwarf planet Pluto, however, the predicted temperature based on the composition of its atmosphere was much higher than actual measurements taken by NASA's New Horizons spacecraft in 2015. A new study proposes a novel cooling mechanism controlled by haze particles to account for Pluto's frigid atmosphere.
The trans-neptunian belt contains four dwarf planets, among which Haumea stands out for its extremely elongated shape and rapid rotation. A stellar occultation makes it possible to establish the main physical characteristics of this previously little known body -- among which most surprising was the presence of a ring.
It might be lingering bashfully on the icy outer edges of our solar system, hiding in the dark, but subtly pulling strings behind the scenes: stretching out the orbits of distant bodies, perhaps even tilting the entire solar system to one side. It is a possible "Planet Nine" -- a world perhaps 10 times the mass of Earth and 20 times farther from the sun than Neptune.
The Working Group for Planetary System Nomenclature of the International Astronomical Union has officially approved the naming of 14 features on the surface of Pluto. These are the first geological features on the planet to be named following the close flyby by the New Horizons spacecraft in July 2015.