As Johns Hopkins astrophysicist Carey Lisse, who led the Chandra team, put it: “Pluto is interacting with the solar wind in an unexpected and energetic fashion”.
Lisse, who also holds the laurel for discovering X-rays emanating from comets, says the solar wind's charged particles are probably the source of the necessary energy.
However, as NASA says in this
media release, there's somewhat more X-ray activity than scientists expected.
“Although Pluto is releasing enough gas from its atmosphere to make the observed X-rays, in simple models for the intensity of the solar wind at the distance of Pluto, there isn't enough solar wind flowing directly at Pluto to make them,” the statement says.
