Air temperature is measured about 6 feet above the ground in a ventilated shelter that is painted white. This method allows the temperature “in the shade” of air passing through the shelter.

Using this process Death Valley, CA is known as the hottest place on Earth due to the Furnace Creek, CA temperature of 134.1°F (56.7°C) recorded on July 10, 1913.

That’s air temperature, ground surface temperatures are a different beast.

Over the past 20 years NASA has been using satellites equipped with a Moderate Resolution Imaging Spectroradiometer (MODIS) to measure the infrared heat emitted by surfaces like dirt, rocks, etc. to see how hot they get. You’ve certainly experienced touching really hot surfaces during a sunny day (think metal car door). Radiation from the sun mercilessly heats these objects on sunny days.

Using the MODIS data there are two places that have leaped to the top of the surface heat heap; the Lut Desert in Iran, and the Sonoran Desert along the U.S.-Mexico border where temperatures have reached 177.4°F (80.8°C).

The Lut Desert has a larger area with these scorching surface temperatures and is now considered to be the “Hottest Place on Earth”.

In this Month’s Bulletin of the American Meteorological Society researcher Yunxia Zhao of the University of California, Irvine reveals other mind-bending facts about temperatures here on planet Earth:

The biggest temperature swing in a single day : 147.3°F (81.8°C), from –10.7°F (–23.7°C) to 136.6°F (58.1°C) on July 20, 2006 in China’s Qaidam Basin, a crescent-shaped depression hemmed in by mountains on the Tibetan Plateau.

And the coldest place? No shocker here; with a satellite reading of -167.6°F (-110.9°) recorded in 2016 Antarctica reigns supreme.