Honolulu — There's been a rare sighting in Hawaii waters of what's believed to be the biggest great white shark on record, reports CBS Honolulu affiliate KGMB-TV. In incredible video taken by OneOcean Diving, a massive great white is seen off Oahu.

The shark in the video is believed to "Deep Blue," which is nearly 20 feet long. She's also believed to be more than 50 years old.

And the divers said she has markings indicating she could be pregnant.

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In the past few years, Blue has become so famous that she even has her own Twitter account.

A shark known as "Deep Blue" swims off Hawaii, U.S. on January 15, 2019 in picture obtained from social media on January 17, 2019 @JuanSharks/@OceanRamsey/Juan Oliphant/oneoceandiving.com via @JuanSharks/@OceanRamsey/Juan Oliphant/oneoceandiving.com via REUTERS

Deep Blue apparently had quite a meal a couple days ago, when she was spotted feeding on a sperm whale carcass about 20 miles off Oahu's southern shore.

In the videos, the shark exhibits calm behavior as divers bravely swam alongside, cage-free.

Deep Blue was last spotted in Mexico, in July.