Bonsoir,
A stellar occultation by Pluto in July 2019 allowed Japanese astronomers to observe its atmosphere and see a 20% decrease in its density compared to its value in 2016, during the meeting of NH and this dwarf planet.
Some uncertainties remain on these measurements and new observations with large telescopes could prove necessary to establish a definitive finding.
https://astronomy.com/news/2020/05/plutos-s...-just-collapsed
Full Version: Surprising collapse of the atmosphere of Pluto
You had naturally corrected. NH flew over Pluto on July 14, 2015. This is a rather special date, especially for a Frenchman. 
This is a "lo-fi" version of our main content. To view the full version with more information, formatting and images, please click here.