Doctor Kathy Sullivan, a former NASA astronaut and geologist, has broken a world record by diving 35,000 feet underwater to the lowest point on Earth.

Sullivan and her pilot Victor Vescovo reached the Challenger Deep in a DSV Limiting Factor, which specializes in deep ocean dives. The Challenger Deep in the southern part of the Pacific Ocean's Mariana Trench, 124 miles east of the Mariana Islands off the coast of the Philippines.

In 1984, Sullivan (68), who has completed three space shuttle flights, became the first American woman to walk in space. 

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Now Dr. Sullivan has become the 8th person to reach the bottom of the Challenger Deep. The feat was also completed by Don Walsh and Jacques Picard in 1960, and film director James Cameron, in 2012. 

Congratulations Kathy Sullivan! The first American woman to walk in space is now the first woman to the Challenger Deep. Thanks for taking OMEGA with you to the deepest place on Earth! #Seamaster pic.twitter.com/WefFUajcLb

— OMEGA (@omegawatches) June 10, 2020

Having completed the dive and returned to the LF mothership, DSSV Pressure Drop, Sullivan and Vescovo phoned the International Space Station. 

She told the Daily Mail "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."

36 years after my space walk, I became the first woman to dive to the deepest known spot in the ocean - the Challenger Deep. #WorldOceansDay pic.twitter.com/KWJxx4fBYR

— Kathy Sullivan (@AstroKDS) June 9, 2020

She added "We made some more history today and then got to share the experience with kindred spirits in the ISS,' added Victor Vescovo, an American undersea explorer who made previous trips to the Mariana Trench.

"It was a pleasure to have Kathy along both as an oceanographer during the dive, and then as an astronaut to talk to the ISS."

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