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What lies beneath the waves is one of the greatest mysteries of our planet.
About half of the Earth’s surface remains unknown and unexplored, partly because humans have only mapped a quarter of the seafloor, which covers about 70% of the planet, in high resolution.
So how do you find things you can’t see? Technologies like sonar and remote-operated vehicles, which use sound waves to identify objects in the water, have helped explore the dark ocean depths, revealing unknown species, geological features, and mysterious phenomena.
Oceanographers aim to have a precise map of the seafloor by 2030, and a thrilling underwater discovery announced this week brings that goal a little closer to reality.
Ocean Secrets
Many of the world’s tallest mountains cannot be seen from land; they rise thousands of feet above the sea floor.
An expedition to the Nazca Ridge, 900 miles off the coast of Chile, has mapped and studied a newly discovered underwater mountain that is four times higher than the world’s tallest building.
What’s more, the underwater mountaintops, cliffs and ridges are home to coral gardens that are home to rare deep-dwelling octopuses, squid and creatures known as flying spaghetti monsters—some of which had not been well documented before this research.
The Nazca Ridge is one of several ocean areas considered for recognition as an offshore marine protected area under a newly adopted United Nations treaty.
Defying gravity
Polaris Dawn, the ambitious mission to fly four civilians in a SpaceX capsule to perform the world’s first commercial spacewalk, failed to launch this week.
Problems with equipment on the launch pad at NASA Kennedy Space Center in Florida first caused a 24-hour delay, followed by another delay caused by unfavorable weather conditions for landing.
Earlier in the week, the Federal Aviation Administration’s investigation into SpaceX’s Falcon 9 rocket, which will power the first leg of the Polaris Dawn crew’s journey into orbit, added another layer of uncertainty. Another rocket in the same family failed to land properly and exploded on Wednesday after launching a Starlink satellite, prompting the FAA to ground the craft.
The Falcon 9 has been cleared to fly again, but it’s not yet clear when the Polaris mission will lift off. For now, four crew members, including billionaire Jared Isaacman, remain in quarantine.
Dino-mite
Paleontologists have found matching dinosaur footprints on different continents and in an ocean 4,000 miles apart.
Although the 260 footprints preserved in mud and silt in what are now Brazil and Cameroon are similar in age, shape and geological context, it is not possible to know for sure whether they were made by the same species.
Most of the fossilized footprints belong to three-toed theropod dinosaurs, while a few are thought to belong to sauropods, which were bulky quadrupeds with long necks and tails, or ornithischians with pelvic structures similar to birds.
The discovery is clear evidence that 120 million years ago, the Earth was home to a massive landmass known as Gondwana, which created ideal conditions for dinosaurs before supercontinents broke apart and became the seven continents we know today.
Other worlds
The James Webb Space Telescope has detected six irregular planets larger than Jupiter that do not orbit a star.
Astronomers discovered these celestial objects in a star-forming nebula, or cloud of gas and dust, called NGC 1333. The nebula lies 960 light-years away within a larger region of gas and dust called the Perseus molecular cloud.
Observations with the telescope will help astronomers understand how these free-floating worlds evolved.
It is possible that planet-like objects initially formed around and in orbit around stars, but were thrown into space as a result of gravitational interactions with other objects.
Long ago
Paleontologists have solved a prehistoric cold case by revealing how the manatee, a creature resembling a sea cow, met a violent end some 15 million years ago.
Bite marks on the unusual fossil, found in what is now Venezuela, suggest the ancient marine mammal was killed by a crocodile, which sank its teeth into the manatee’s snout, sending it into a downward death spiral – a tactic that modern crocodiles also use to incapacitate their prey.
Later, paleontologists believe a shark fed on the remains of the sea cow. Smoking gun? A tooth belonging to a tiger shark, a scavenger, was found lodged in the fossil’s neck.
Discoveries
Check out these mind-expanding stories:
— NASA’s DART mission may have created the first man-made meteor shower. But it will take years to know for sure.
— A sunken bridge could reveal when the islands of the Mediterranean were first inhabited.
— Marmosets use their names to communicate, joining the short list of species that exhibit complex behaviors in this way.
— Boeing’s troubled Starliner spacecraft finally has a return date. But it will return to Earth without its crew.
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