Record Set for Hottest Temperature on Earth: 3.6 Billion Degrees F in Lab that's only 2 billion KelvinScientists have produced superheated gas exceeding temperatures of 2 billion degrees Kelvin, or 3.6 billion degrees Fahrenheit. This is hotter than the interior of our Sun, which is about 15 million degrees Kelvin, and also hotter than any previous temperature ever achieved on Earth, they say. They don't know how they did it. The feat was accomplished in the Z machine at Sandia National Laboratories. "At first, we were disbelieving," said project leader Chris Deeney. "We repeated the experiment many times to make sure we had a true result." let the speculation begin