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When a star strays too close to a supermassive black hole, extreme gravitational forces ravage it, shredding and stretching it into spaghetti. 

The term for this gruesome process is actually “spaghettification,” according to NASA, inspired by Stephen Hawking’s book, A Brief History of Time. In it, the late theoretical physicist first described what would happen to a person approaching a black hole’s “event horizon” — its point of no return — in space.

Astronomers used to think this was an immediate death sentence for a star. Now an international team, led by Tel Aviv University in Israel, has published the first confirmed case of a star surviving such a brush, only to return 700 days later for another go. 

The findings, which appear in The Astrophysical Journal Letters, don’t contradict the concept of spaghettification but show that it could be a repeatable process for some stars, said Iair Arcavi, who supervised the research.

“A star isn’t a uniform ball of matter,” Arcavi told Mashable. “The inner part is more dense, and the outer part is more ‘fluffy.’ So the outer part is more easily spaghettified. If the star kept to some distance from the black hole, it could avoid the denser parts from getting spaghettified, too.” 

Black holes are some of the most inscrutable phenomena in the universe. They are regions in space where gravity is so intense that nothing, not even light, can escape. About 50 years ago, they were little more than a theory — a kooky mathematical solution to a physics problem. Even astronomers at the top of their field weren’t entirely convinced they existed. 

Today, not only are black holes accepted science, they’re getting their pictures taken by a collection of enormous, synced-up radio dishes on Earth. Humanity got a clear view of Sagittarius A*, the black hole at the center of the galaxy, for the first time in 2022. 

Last year, Tel Aviv University researchers spotted a tidal disruption event (TDE) near the center of a galaxy about 400 million light-years away using the Las Cumbres Observatory, a network of robotic telescopes around the world, designed to keep a close eye on rapid cosmic events. These TDEs are bright flares that occur when a black hole is destroying a star. 

What shocked them was that the flare was almost identical to another that occurred two years earlier, called AT 2022dbl, from the exact same location. After analyzing the data, scientists ruled out other explanations, like unrelated flares or gravitational lensing, and concluded that the same star was partially torn apart twice.

Typically, when a star is pulled toward a black hole, its near side is stretched and pulled in while the far side is flung out. The resulting stream of gas and debris spirals around the black hole as it falls in — sort of like water circling a bathtub drain. These bursts of energy can outshine an entire galaxy, briefly illuminating the hidden black hole lurking at the heart of a galaxy.

Over the past decade, astronomers have observed dozens of these flares. But one thing has perplexed them: Based on computer simulations, most of these events seem kind of weak. Previously, scientists had assumed the discrepancy between real and virtual flares has been due to knowledge gaps or the limitations of computer models.

But AT 2022dbl’s repeating flare may offer a simpler explanation. The star may not have been completely annihilated on its first trip around the black hole. Then, like a masochist, it returned roughly two years later to be damaged again.

The study suggests it’s possible many of these flares, once thought the calling cards of stellar death, aren’t necessarily fatal events. The question now is whether this particular star is finally dead or if it’ll be back again next year for more abuse.

Either way, Arcavi said, astronomers will have to rethink these flares and what they say about the monsters lying in wait.

Nature has rewritten the rules of survival more than once throughout the history of existence, witnessing asteroid impacts, super volcanoes, and the causes of mass extinction. There are many reasons for the complete disappearance of species, and one of these silent killers is ocean acidification, which is due to the buildup of carbon dioxide (CO₂) in the atmosphere, which then dissolves into seawater and disrupts marine chemistry.While many people associate today’s rising CO₂ levels and warming oceans with modern industrial activity, similar events have happened in Earth’s distant past, even long before humans ever walked the planet.Scientists now believe that carbon-driven ocean acidification was a major factor in some of Earth’s most significant mass extinction events, and surprisingly, the patterns from the past look similar to what we’re experiencing today.A study that was published in Nature Communications sheds light on one such ancient crisis

Acidification of the ocean can be harmful to the Earth’s future

Roughly 201 million years ago, at the boundary between the Triassic and Jurassic periods, Earth’s oceans went through a major crisis. New research from the University of St Andrews and the University of Birmingham has confirmed that a sharp and prolonged drop in ocean pH, caused by a massive carbon dioxide surge, contributed directly to a global extinction event.

What was the study all about?

The study, led by scientists including Dr. James Rae and Dr. Sarah Greene, is the first to fully reconstruct ancient ocean pH levels using boron isotopes found in fossil oysters. These specimens were collected from Lavernock Point in Wales, which showed a significant drop in pH by at least 0.29 units, possibly more than 0.41. According to the researchers, this corresponds to a CO₂ level over 1300 parts per million (ppm). For comparison, current CO₂ levels are around 420 ppm.“The geological record tells us that major CO₂ release transforms the face of our planet, acidifying the ocean, and causing mass extinction,” said Dr. Rae in the university press release. “We have to act fast to avoid these outcomes in our future.”

The carbon release, estimated at over 10,000 gigatons, was likely driven by volcanic activity as the supercontinent Pangaea began to break apart. The resulting acidification devastated coral reefs and shell-forming marine life, creating a “reef gap” that lasted hundreds of thousands of years.Dr. Greene said, “This warning from the past should give us fresh cause to step up efforts to reduce human greenhouse gas emissions.”Today’s acidification is happening even faster, making this ancient event a chilling parallel and a reminder that Earth doesn’t need an asteroid to spark a mass extinction. Sometimes, it can only be rising carbon levels due to pollution.

Astronomers have potentially captured the HD 135344B planet during its formation process, allowing for a new understanding of how planetary systems like ours come into existence

Using the European Southern Observatory’s (ESO) Very Large Telescope (VLT) in Chile, researchers have observed a young star, HD 135344B, surrounded by a disc of swirling gas and dust, with clear evidence of a planet carving out spiral arms within it.

This discovery marks the first time scientists have directly detected a planet candidate embedded inside a spiral pattern in a protoplanetary disc, the material surrounding a young star from which planets form.

A planet carving spirals

The star HD 135344B, located 440 light-years away in the constellation Lupus, is enveloped by a dense protoplanetary disc. These discs often feature rings, gaps, and spiral structures believed to be shaped by the gravitational influence of forming planets. While previous studies had observed spiral arms in this system, none had successfully identified the presence of a planet causing the pattern until now.

Using the VLT’s state-of-the-art ERIS (Enhanced Resolution Imager and Spectrograph) instrument, scientists detected a compact, bright signal at the base of one of the disc’s spiral arms. This signal is believed to be the light emitted by a planet still embedded in the disc, suggesting it is actively shaping the surrounding gas and dust as it grows.

This planet candidate is estimated to be about twice the mass of Jupiter and lies at a distance from its star similar to Neptune’s orbit around the Sun.

Planet hunting

The ERIS instrument, installed on the VLT in 2022, is proving to be a game-changer for direct imaging of young planetary systems. It allows astronomers to look deeper into dusty regions around young stars and detect faint objects that older technologies may have overlooked.

In the case of HD 135344B, ERIS enabled astronomers not only to see the spiral structures in greater detail but also to identify the likely cause: a forming planet. This represents a key step forward in confirming long-standing theories about how young planets influence their birth environments.

A young system under the microscope

In a separate but relevant study, another group of astronomers used ERIS to investigate a young star known as V960 Mon, also surrounded by a spiral-patterned disc. This system has exhibited signs of gravitational instability, where clumps of gas and dust collapse under their gravity, potentially leading to the formation of planets or brown dwarfs.

The team found a compact, luminous object near one of the spiral arms. Though its exact nature is still uncertain, it could be either a forming planet or a brown dwarf, an object too large to be a planet but not massive enough to ignite as a star.

If confirmed, this would be the first clear evidence of such an object forming through gravitational instability.

These observations open up new opportunities to witness planet formation as it happens, offering clues to understanding how planets, including those in our own solar system, form and evolve.