Models and lab tests suggest the asteroid could be venting sodium vapor as it orbits close to the Sun, explaining its increase in brightness.

PASADENA, Calif. (NASA PR) — As a comet zooms through the inner solar system, the Sun heats it, causing ices below the surface to vaporize into space. The venting vapor dislodges dust and rock, and the gas creates a bright tail that can extend millions of miles from the nucleus like an ethereal veil.

• In 2024, the Japanese-German space mission DESTINY⁺ will launch on a journey to asteroid 3200 Phaethon.
• The mission’s key instrument is the German DESTINY⁺ Dust Analyzer (DDA), which will collect and analyse cosmic dust samples during the entire flight of the spacecraft.
• The cooperation agreement for the bilateral mission was signed by DLR and JAXA on 11 November 2020 as part of a joint strategy dialogue meeting.

COLOGNE (DLR PR) — How did life arrive on Earth? To investigate this and to address fundamental questions about the evolution of celestial bodies in our Solar System, the Japanese-German space mission DESTINY⁺  (Demonstration and Experiment of Space Technology for  INterplanetary voYage with Phaethon fLyby and dUst Science), will launch in 2024 on a journey to asteroid 3200 Phaethon.