A few months after the Yellowstone Supervolcano had erupted, the US Geological Survey organized an overflight of the crater. While most US commercial aviation was still grounded due to ash in the air, the USGS managed to charter a Learjet for the mission. The aircraft carried a number of geology professors and their graduate students including Prof. Geoff Rheinburg and his student Kelly Birnbaum along with sensors and other equipment to analyze the crater.
The Learjet took-off from Oakland International Airport and the first part of the flight of about an hour and a half was routine. The aircraft flew smoothly at 40,000 feet and 500 mph. However, as soon as they flew over the edge of the crater, turbulence increased greatly due to the heat from the still molten interior. Looking down Birnbaum could see that parts of the floor had crusted over with dark rock but most of it remained glowing and bubbling lava.
Once they flew out of the hot air over the crater, the air became smooth once more. The jet took a long U-turn over Wyoming and headed back towards the crater for a second pass. Turbulence reoccurred and then stillness returned when the jet entered Idaho. Both Rheinburg and Birnbaum were sobered by the destruction they saw but pleased with the information they had collected.
Afterwards, Birnbaum showed pictures she had taken to her boyfriend Colin Ferguson who remarked they reminded him of Jupiter's sausage-and-anchovy pizza moon Io. Birnbaum was amused but at the time she had been reminded of the volcanic scenes in Return of the King from the movie version of Tolkien's The Lord of the Rings.