Monster gravitational waves spotted

Gravitational waves are back, and they’re bigger than ever. Researchers have spotted hints of space-time ripples that are light-years long, and thousands of times stronger and longer than the first gravitational waves ever found, in 2015. The first detection used the ground-based Laser Interferometer Gravitational-Wave Observatory (LIGO) detector — this time, scientists tracked changes in the distances between Earth and beacon stars called pulsars to reveal how passing gravitational waves stretch and squeeze space. The waves’ most likely source is the combined signal from many pairs of enormous black holes slowly orbiting each other in the hearts of distant galaxies.

Ancient humans probably ate each other

A carved-up leg bone might be the earliest evidence that ancient humans butchered and ate each other’s flesh. The 1.45-million-year-old hominin bone features cuts similar to the butchery marks made by stone tools found on fossilised animal bones. The scrapes are located at an opportune spot for removing muscle, suggesting that they were made with the intention of carving up the carcass for food. It isn’t possible to say whether this is an example of cannibalism, because the bone belongs to an unidentified hominin species.

Physicists split bits of sound using quantum mechanics

Mechanical waves can be put into superposition, the ability of quantum systems to be in multiple states at the same time until they are measured. Superposition has been demonstrated for quantum particles such as electrons and photons. Quantised sound waves called phonons can also live parallel quantum lives when they’re faced with an acoustic beam splitter, a barrier that phonons can either pass through or bounce back from. It's a step towards building quantum computers that can encode and process information in phonons.

Another exoplanet with no atmosphere

The James Webb Space Telescope has failed, for the second time, to find a thick atmosphere on an exoplanet in the TRAPPIST-1 system, a planetary system that could be hospitable to life. Like its neighbour TRAPPIST-1 b, the planet TRAPPIST-1 c probably never had many ingredients for habitability. There is still a chance that some of the five other TRAPPIST-1 planets might have atmospheres containing geologically and biologically interesting compounds.

‘Breakthrough’ could explain why life molecules are left- or right-handed

Magnetic minerals that were common on ancient Earth might be why nature shows a preference for the ‘left handed’ or ‘right handed’ versions of certain molecules that are essential for life. Some molecules have two mirror-image ‘chiral’ forms, and biology chooses just one: DNA, RNA and their building blocks are all right-handed; amino acids and proteins are all left-handed. Researchers found that magnetic minerals could have created an early surfeit of one-handed versions by causing more of one type to settle on their surfaces, kicking off the biological bias towards a single chiral form.

Laos cave fossils prompt rethink of human migration map

Two human bone fragments — from a skull and a leg — have been unearthed in the Tam Pà Ling cave in Laos. The fossils are older than previous finds from the cave and suggest that early modern humans were in the area up to 86,000 years ago. That’s earlier than previously thought, and calls into question hypotheses that Homo sapiens dispersed out of Africa and through Asia in a single rapid event that happened after the ending of a geological period 80,000 years ago.

A New Experiment Casts Doubt on the Leading Theory of the Nucleus

The leading theory of what’s going on inside atoms can’t properly describe the strong nuclear force. This fundamental interaction binds together protons and neutrons inside an atom’s core. The results of an experiment that measured inflated atomic nuclei, contradicted the theory. It’s still unclear whether the discrepancy could be resolved by including commonly ignored factors in the theoretical calculations or whether there’s a fatal flaw in our understanding of the strong force.

A ‘lost world’ of early microbes thrived one billion years ago

Scientists have discovered a ‘lost world’ of early microorganisms that once thrived in the world’s oceans. Eukaryotes (the group that includes amoebae, mushrooms, plants and people) were thought by some to have become abundant only around 800 million years ago. That’s when ancient rocks bear the telltale signs of the organisms’ existence in the form of fat-like molecules called sterols. But it turns out that precursor ‘protosterol’ molecules are present in rocks dating back even further, to 1.6 billion years ago. The now-extinct eukaryotes that produced these protosterols lived in watery environments between 800 million and 1.6 billion years ago, but were replaced by modern sterol-producing eukaryotes by the end of that period.

JWST spots the most distant ‘smoke’ molecules ever seen in space

The James Webb Space Telescope (JWST) has spied a ‘smoke ring’ of polycyclic aromatic hydrocarbons in a faraway galaxy. The compounds, which are also found in soot and smoke, form near young, massive stars. Because the galaxy is so distant that it appears as it did when the Universe was just 10% of its current age, it must have been busy creating stars during that time.

This infinite tiling pattern could end a 60-year mathematical quest

After 60 years of searching, mathematicians might have finally found a true single aperiodic tile — a shape that can cover an infinite plane and never make a repeating pattern. In March, a team of hobbyist and professional mathematicians found a shape that, together with its mirror image, could be used to build infinite aperiodic tilings. The same team has now modified the shape so it doesn’t need its mirror image to create the never-repeating pattern.