Ice core may hold answers to mysteries of Earth’s past

By Ashley Strickland, CNN

(CNN) — One of the best ways to assemble the puzzle pieces of Earth’s past is hiding deep beneath its white polar sheets: ice cores.

These frozen time capsules preserve air bubbles from thousands of years ago, painting a picture of climate and environmental conditions at the time to reveal how much our planet has changed.

Ice cores can show how temperatures have fluctuated in the distant past and preview how quickly sea levels could rise in the future if warming caused by greenhouse gas emissions isn’t curbed.

The deeper the cores go, the more history they contain — and the icy layers could also solve some of the biggest questions about mysterious eras in Earth’s 4.5 billion-year history.

Once upon a planet

A research team has collected what may be among the oldest ice samples on Earth.

The team, with members from 12 European scientific institutions, drilled and retrieved a 9,186-foot-long (2,800-meter) ice core from the Antarctic ice sheet. The sample extended so deep that scientists reached the bedrock beneath it.

The ice core spans at least 1.2 million years of Earth’s climate history.

Air bubbles and particles trapped inside the ice could also reveal why the planet’s ice ages suddenly became longer and more intense about 1 million years ago, which may have caused ancient human populations to plummet.

Ocean secrets

Tahlequah, a mother orca, became known around the world in 2018 for the heartbreaking act of carrying her dead calf for more than 1,000 miles (1,600 kilometers) over 17 days. Now, she appears to be grieving a second tragic loss.

Her newest calf was spotted on December 20 in Washington state’s Puget Sound, but by New Year’s Eve, scientists confirmed the baby orca had died. As before, Tahlequah began carrying her lost calf.

The orca’s act of mourning, in which she nudges the deceased calf’s 300-pound (136-kilogram) body to prevent it from floating away, has raised concern among researchers — not only for the emotional and physical toll it could take but also its impact on Tahlequah as a member of a highly vulnerable killer whale population.

Defying gravity

The long-delayed maiden flight of a rocket that could challenge SpaceX’s dominance in the commercial space industry is set to blast off from a Florida launchpad as soon as early Sunday morning.

The uncrewed vehicle, named New Glenn after storied NASA astronaut John Glenn, will mark the first attempt by Jeff Bezos’ company Blue Origin to send a rocket into orbit.

The company’s most powerful rocket could one day be used to ferry Amazon internet satellites to space or assist in constructing a space station Blue Origin is developing with its partners.

When New Glenn launches, Blue Origin will attempt to guide its first-stage rocket booster back for a safe landing. But remember: Smooth flights are never guaranteed for inaugural missions.

Other worlds

Pluto is a bit of an outlier in our solar system because the dwarf planet has an unusually large moon. Astronomers have tried to solve the riddle of why Pluto shares an orbit with a satellite about half its size, and how the moon came to be in the first place.

New research suggests that the two icy, rocky bodies came together about 4 billion years ago in a newly discovered type of collision called a “kiss and capture.”

Rather than melting together or ricocheting, Pluto and Charon essentially merged in a cosmic snowman-like shape before gradually separating again into the orbit they share now.

Scientists think the odd collision may be responsible for the subsurface ocean suspected to exist beneath Pluto’s icy crust.

Dino-mite!

While extracting limestone from Dewars Farm Quarry in Oxfordshire, England, quarry worker Gary Johnson sensed “unusual bumps” on the ground. Detecting the bumps led to the unearthing of a “dinosaur highway,” a pathway of nearly 200 dinosaur footprints dating back 166 million years.

The astonishing find is the largest known dinosaur track site in the United Kingdom.

Some of the trackways belonged to lumbering long-necked dinosaurs such as Cetiosaurus and massive three-toed predators such as Megalosaurus, revealing insights about their behaviors as well as the speed at which the creatures moved.

“It’s like a snapshot into the day of the (dinosaurs’) life, and what they were doing,” said Kirsty Edgar, a professor of micropaleontology at England’s University of Birmingham.

Curiosities

Take a closer look:

— Sixteenth-century explorer Antonio Pigafetta described golden lion tamarins, found in eastern Brazil, as “beautiful, simian-like cats similar to small lions.” Once on the brink of extinction, the endangered small monkeys are making a comeback, thanks to conservation efforts.

— Retrieving crucial samples from Mars is a complex endeavor. By 2026, NASA will decide between two key proposals to return a cache that could help determine whether life ever existed beyond Earth.

— Water hyacinth, which can choke fish and trap boats, is the world’s most widespread invasive species. Now, a Kenyan company is turning the problematic plant into a bioplastic that could help with reforestation efforts.

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