Do they come in peace? Depends who you ask. Stories abound of unidentified flying objects, some of which have even been investigated by secretive government agencies (paging Fox Mulder!). In March 2018, an FAA recording revealed two airline pilots having close encounters of the UFO kind. Those reports have yet to be explained, though it's worth noting that previous UFO reports, like those surrounding Area 51 in Roswell, New Mexico, have their roots in experimental military technology.
True's beaked whale is another deep-sea creature that's rarely seen. But in 2017, researchers captured this elusive creature on video for the first time. The True's beaked whale can dive as deep as 10,000 feet (3,000 m) and needs to surface for only brief periods to take a breath. Scientists estimate they spend 92 percent of their time under water.
True's beaked whales are one of 22 known species of beaked whale. They get their name thanks to their pointed, almost dolphin-like snouts.
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Denise Chow was the assistant managing editor at Live Science before moving to NBC News as a science reporter, where she focuses on general science and climate change. Before joining the Live Science team in 2013, she spent two years as a staff writer for Space.com, writing about rocket launches and covering NASA's final three space shuttle missions. A Canadian transplant, Denise has a bachelor's degree from the University of Toronto, and a master's degree in journalism from New York University.