Question: What stratosphere pioneer studied Earth's upper atmosphere and cosmic rays?
Sentence (from "Auguste Piccard"): Auguste Antoine Piccard (28 January 1884 – 24 March 1962) was a Swiss physicist, inventor and explorer, known for his record-breaking hot air balloon flights, with which he studied Earth's upper atmosphere and cosmic rays, and for his invention of the first bathyscaphe, "FNRS-2", with which he made a number of unmanned dives in 1948 to explore the ocean's depths.
Relevant evidence: Yes