This week’s biggest science news took us to a region 140 million-light-years away, where scientists have discovered the largest spinning object in the known universe. The enormous rotating filament is wider than the Milky Way and is linked to a daisy-chain of 14 galaxies, which is how astronomers found it. The filament is whirling at around 68 miles per second (110 kilometers per second).

Closer to home, researchers looked to southern Africa, where a human population was genetically isolated for 100,000 years.

The study looked at a number of human skeletons that were up to 10,000 years old and were found south of the Limpopo River, which begins in South Africa and flows east through Mozambique to the ocean. All of the remains from people who lived more than 1,400 years ago had a dramatically different genetic makeup than modern humans. These people “form an extreme end of human genetic variation,” the researchers wrote in the study.

On the other side of the world, archaeologists in China unearthed a massive pit of skulls outside the gates of a 4,000-year-old city. What puzzled archaeologists, however, was that almost all the skulls were from males — a big departure from the human sacrificial pattern found in other nearby settlements. Archaeologists were also baffled by a 2,700-year-old elaborate tomb in Greece that contained a woman wearing an upside-down crown.

In some disconcerting modern-day news, a massive ecosystem engineering project initiated in China decades ago had some unintended consequences. As part of the Great Green Wall, China initiated a major tree-planting project to stave off desertification. But while the efforts worked, they also changed rainfall and evaporation patterns across the country, leading to lower water levels in some of the most populous parts of the country, a new analysis revealed.

Speaking of deserts, the world’s hottest temperature record, set in Death Valley in 1913, may have been due to human error, new research finds. And in Europe, the collapse of a key Atlantic current could lead to centuries of drought.

The world has been fascinated by interstellar visitor comet 3I/ATLAS since it zoomed into our consciousness in July. Since then, we’ve learned tons about the cosmic interloper, which is not an alien spacecraft. Now researchers have trained their sights on the speedy space rock using the Joan Oró Telescope at the Montsec Observatory in northeastern Spain, and paired its observations with those made by other observatories in the region. The team noticed that the comet heated up and brightened rapidly as it approached the sun, which is a clue that ice is sublimating from its surface. That would make 3I/ATLAS similar to other objects in our solar system, such as the dwarf planets that orbit beyond Neptune.

Discover more space news
—James Webb telescope spots strange ‘super-puff’ planet frantically chasing its own atmosphere through space
—An extra solar system planet once orbited next to Earth — and it may be the reason we have a moon
—Russia accidentally destroys its only working launch pad as astronauts lift off to ISS

Dreaming is a nearly universal human experience. But there can be huge variations in how vivid, realistic or memorable different people’s dreams are. But what about the dreams of the same person — do they change as a person ages?

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Researchers at MIT have found a way to suck the water out of the air and turn it into drinking water — and the process takes just minutes. Past evaporation water harvesting systems cool moist air or use spongy materials to absorb water vapor and condense it into droplets. Past versions typically rely on sunlight to power the evaporation, which can take hours or days and doesn’t work in dry regions.

The new method uses sound waves to shake the liquid from the sponges and is 45 times more efficient than relying on evaporation alone, the researchers say. One challenge of the new device, however, is that it needs a power source, but the researchers think they can get around this problem by pairing their device with a solar cell.

Discover more technology news
—When an AI algorithm is labeled ‘female,’ people are more likely to exploit it
—New ‘physics shortcut’ lets laptops tackle quantum problems once reserved for supercomputers and AI

—Law of ‘maximal randomness’ explains how broken objects shatter in the most annoying way possible
—Injecting anesthetic into a ‘lazy eye’ may correct it, early study suggests
—Anacondas became massive 12 million years ago — and it worked so well, they haven’t changed size since
—Volcanic eruption triggered ‘butterfly effect’ that led to the Black Death, researchers find

Helium is used in MRI machines, superconductors and quantum computers — and there’s a massive shortage looming. Historically, helium was only found in tiny quantities alongside natural gas, which made extracting usable helium a huge source of carbon emissions. But as Live Science staff writer Sascha Pare discovered, a handful of enormous, highly concentrated, carbon-free helium reservoirs have changed the geological picture.

Can that help us find other massive helium caches — and solve the helium shortage?

While excavating in Bolivia’s Carreras Pampa tracksite, scientists found more than 18,000 fossilized dinosaur footprints and swim marks. The vast trail of ancient footprints spans an area of 80,570 square feet (7,485 square meters), and the sheer size of the area is visible in a video the researchers took of the site.

If you’re looking for something a little longer to read over the weekend, here are some of the best interviews, opinion pieces and science histories published this week.

—‘Intelligence comes at a price, and for many species, the benefits just aren’t worth it’: A neuroscientist’s take on how human intellect evolved [Interview]
—Your AI-generated image of a cat riding a banana exists because of children clawing through the dirt for toxic elements. Is it really worth it? [Opinion]
—Science history: Computer scientist lays out ‘Moore’s law,’ guiding chip design for a half century — Dec. 2, 1964 [Science history]

Tia is the editor-in-chief (premium) and was formerly managing editor and senior writer for Live Science. Her work has appeared in Scientific American, Wired.com, Science News and other outlets. She holds a master’s degree in bioengineering from the University of Washington, a graduate certificate in science writing from UC Santa Cruz and a bachelor’s degree in mechanical engineering from the University of Texas at Austin. Tia was part of a team at the Milwaukee Journal Sentinel that published the Empty Cradles series on preterm births, which won multiple awards, including the 2012 Casey Medal for Meritorious Journalism.