Jian-Rong Gao and his team are working very hard on project GUSTO. If all goes to plan, GUSTO (a helium balloon the size of a soccer stadium with a NASA telescope) will lift off from Antarctica in December 2021, reaching an altitude of 36 kilometers.
TU Delft wrote an interesting article about this project, where they elaborate about the project and the techniques and detectors used in the project. You can find the story here!