The deepest point in Earth's ocean has been visited by a woman for the first time.
On Sunday, former NASA astronaut Kathy Sullivan reached the bottom of the Challenger Deep, almost 6.9 miles (11,000 meters) below the surface of the Pacific Ocean, according to EYOS Expeditions. Challenger Deep is considered the deepest point in Earth's oceans and resides within the Mariana Trench, a mighty, sickle-shaped depression lying about 1,100 miles east of the Philippines. The pressure at the bottom is over 1,000 times the pressure at sea level.
Sullivan was accompanied by Victor Vescovo, an entrepreneur and deep sea explorer, in the deep sea submersible Limiting Factor. In total, the expedition lasted just under four hours.
The history-making dive was part of the Ring of Fire expedition organized by Caladan Oceanic, a deep-sea exploration company founded by Vescovo. Caladan and Vescovo also oversaw the Five Deeps expedition, whichin 2019. The new expedition is expected to provide the first 4K video of the Challenger Deep.
Upon the pair's return, EYOS coordinated a call between the duo and the International Space Station, allowing them to discuss their journey with another group of history-making explorers: the US astronauts recently.
"As a hybrid oceanographer and astronaut this was an extraordinary day, a once in a lifetime day, seeing the moonscape of the Challenger Deep and then comparing notes with my colleagues on the ISS about our remarkable reusable inner-space outer-spacecraft," she said in a statement.
Vescovo funded the new mission and sent a "big congratulations" to Sullivan in a tweet posted Sunday.
The word "challenger" has become a bit of a theme in Sullivan's expeditions off the surface of the Earth.
She was part of NASA's historic STS-41-G mission, the sixth flight of the space shuttle Challenger and first to include two women in the crew. On Oct. 11, 1984, she performed a three hour and 29 minute EVA -- a spacewalk -- the first ever by an American woman. The mission also carried Sally Ride, the first American woman in space, and Paul Scully-Power,.