The moon is tidally locked with Earth, meaning the same side always faces our planet. The far side is less explored than the near side. Only two landers, both from China, have made it to the moon's far side.

In a study published Nov. 15 in the journal Science, researchers analyzed rock samples returned to Earth by the Chang'e 6 lander. The 2024 mission brought back a little over 4 pounds (1.9 kilograms) of rock from the South Pole-Aitken basin — the first samples ever brought to Earth from the moon's far side.

Zexian Cui of the Chinese Academy of Sciences' Guangzhou Institute of Geochemistry and colleagues analyzed the isotopes in these samples, as well as their chemical makeup, to find their age and source. Isotopes are atoms of an element that have the same number of protons in their nuclei but a different number of neutrons. The number of neutrons changes over time during radioactive decay, making the ratio of different isotopes in a sample a good way to measure how old that sample is.

Related: The oldest evidence of Earth's atmosphere may be hiding in rocks on the moon

The study found that the rocks — hardened lava called basalt — were 2.8 billion years old. Previous research had found volcanism on the near side of the moon until at least 2 billion years ago, and the new dates reveal that the far side of the moon was volcanically active as well. Another recent study of samples from the Chang'e 5 rover, which landed on the near side of the moon in 2020, even hints that volcanoes may have been erupting on the moon as recently as 120 million years ago.

The researchers also found that the lava that made the basalt came from a part of the moon's mantle that was low in potassium, rare Earth elements and phosphorus. These elements are widespread in the lava on the near side of the moon. The puzzling imbalance may be due to the impact crater that made the South Pole-Aitken basin, Cui and his colleagues wrote. The impact, which was large enough to reverberate all the way across the moon, may have redistributed rocks containing those elements, as well as melted the mantle directly below the impact site, depleting it of those elements.

The elemental imbalance may explain another odd difference between the two sides of the moon: Giant lava flows called mare basalts cover 30% of the near side but only 2% of the far side. Some of the missing elements on the far side, such as potassium and uranium, are radioactive and give off heat as they decay, the authors said. Their absence in the mantle under the moon's far side could explain the lack of these melty basalts.

The analysis, which looked at nearly 6 million galaxies and quasars spanning 11 billion years of cosmic time, found that even at colossal scales the force of gravity behaves as predicted by Albert Einstein's theory of general relativity.

The result validates cosmologists' leading theory of the universe and appears to limit alternative theories of gravity, the researchers said. Where the results leave room for new explanations to strange discrepancies in the model, such as the universe's divergent expansion rates at different stages of its life, remains unclear. The researchers published their findings today (Nov. 19) in several papers on the preprint server arXiv and will present them in January at a meeting of the American Astronomical Society in National Harbor, Maryland.

"General relativity has been very well tested at the scale of solar systems, but we also needed to test that our assumption works at much larger scales," Pauline Zarrouk, a cosmologist at the French National Centre for Scientific Research (CNRS) who co-led the analysis, said in a statement. "Studying the rate at which galaxies formed lets us directly test our theories and, so far, we're lining up with what general relativity predicts at cosmological scales."

Cosmologists have long debated the behavior of gravity at large distances. The predominant theory, called the lambda cold dark matter model, builds out from Einstein's theory to offer the most comprehensive view of a wide range of astronomical phenomena.

Related: Researchers spot rare 'triple-ring' galaxy that defies explanation

But doubts about some elements within the model, such as dark matter and dark energy — two mysterious entities that do not interact with light but account for a majority of the mass and energy in the universe — along with the model's inability to predict some observations, have led rival factions to champion alternative explanations.

One of these is modified Newtonian dynamics (MOND), which proposes that for gravitational pulls 10 trillion times smaller than those felt on Earth's surface, such as the tugs between distant galaxies, Newton's laws (which general relativity builds upon) break down and must be replaced by other equations.

To search for clues on how gravity behaves at large scales, the researchers turned to data from the first year of the Dark Energy Spectroscopic Instrument (DESI) mounted on the Nicholas U. Mayall 4-meter Telescope in Arizona, which pinpoints the monthly positions of millions of galaxies to study how the universe expanded up to the present day.

The scientists conducted a "full-shape analysis" that made a precise measurement of the growth of galactic structures over time. It revealed that, while dark energy could be evolving over time, the universe's structure closely matches predictions made by Einstein's theory.

"This is the first time that DESI has looked at the growth of cosmic structure," Dragan Huterer, a professor of theoretical cosmology and astrophysics at the University of Michigan and the co-lead of DESI's group interpreting the cosmological data, said in the statement. "We're showing a tremendous new ability to probe modified gravity and improve constraints on models of dark energy. And it's only the tip of the iceberg."

It's too early to say exactly what this means for our overall view of the cosmos, but the next two years of DESI's collected data is set to be released in spring 2025. The experiment, which is now in its fourth of five years, will collect data from around 40 million galaxies and quasars by the time it ends. If the answers are out there, we may not have to wait too long to find them.

In 2018, astronomers discovered a quartet of identical bright points billions of light-years from Earth, later named J1721+8842. Initially, the scientists assumed that the four lights were mirror images of a single quasar — a luminous galactic core powered by a feeding black hole — that had been duplicated through a phenomenon known as "gravitational lensing."

Gravitational lensing happens when light from a distant object appears to get bent as it passes through warped space-time that has been pulled out of shape by the immense gravity of a lensing object — usually a massive galaxy or cluster of galaxies — located between the distant object and the observer. This warping effect can either duplicate the initial light source, as the light takes different routes around the lensing object, or stretch out the light into luminous halos, known as Einstein rings after Albert Einstein, who first predicted gravitational lensing with his theory of general relativity in 1915.

But in a 2022 study, researchers discovered that J1721+8842 had two additional points of light alongside the original quartet, as well as a faint red Einstein ring. The newly discovered points were slightly fainter than the other four points, which led researchers to suspect that the light show showed a pair of adjacent quasars, known as a binary quasar, that had been duplicated three times (rather than a single quasar that had been copied six times).

Related: Researchers solve mystery of inexplicably dense galaxy at the heart of perfect 'Einstein ring' snapped by James Webb telescope

However, in a new study, uploaded Nov. 8 to the preprint server arXiv, researchers reanalyzed J1721+8842 using new data from JWST and found that all six points of light are actually from a single quasar after all. The team also found that newly unveiled bright spots have been lensed around a second massive object farther away from the first, which is also responsible for the faint Einstein ring seen in more recent images. (The study has not yet been peer-reviewed but has been submitted for publication in the journal Astronomy & Astrophysics.)

After observing the light curves of each bright spot over two years, researchers showed that there is a slight delay in the time it takes the two faintest duplicate images to reach us, which suggests that the light in these copies has to travel farther than the other four bright spots. This is likely because the light in these images passes around the opposite sides of each lensing object (i.e. around the left side of the first lens and right side of the second lens).

The study team has dubbed this "extremely rare lensing configuration" an Einstein zig-zag because light from some of the double-lensed bright spots has swerved back and forth as it passed around both lensing galaxies, the researchers wrote.

Saving cosmology

Gravitationally lensed objects, such as Einstein rings, are treasured by astronomers and cosmologists because the warped light can help reveal the mass of the galaxies that lensed them. This, in turn, can help reveal secrets of the universe such as the secret identity of dark matter and how dark energy drives cosmic expansion.

JWST has been exceptionally good at finding these objects in parts of the universe where we have never been able to see them before. But unfortunately, the state-of-the-art telescope has also highlighted discrepancies we cannot currently explain.

For example, measurements from the telescope have confirmed that different parts of the universe are expanding at different rates, which threatens to "break" our understanding of cosmology. Researchers refer to this problem as the Hubble tension.

However, researchers believe that the newly confirmed Einstein zig-zag could help to smooth out this tension because its unique configuration will allow astronomers to precisely measure both the Hubble constant — the rate at which cosmic expansion is accelerating — and the amount of dark energy — the invisible force driving the universe's expansion — in this region of space. Normally, scientists can only determine exact figures for one or the other but detailed knowledge of both is needed to truly understand cosmic expansion, the researchers wrote.

Thomas Collett, an astrophysicist at the University of Portsmouth in the U.K. who was not involved in the study, told Science magazine that studying the zig-zag will "shine a light on whether the expansion rate of the universe is consistent with the cosmological model or not." However, it could take researchers more than a year to resolve the figures they need from the tangled images, he added. "So we might have to wait a while [for an answer]."

Where it is: 80 million light-years away, in the constellation Canis Major

When it was shared: Oct. 31, 2024

Why it's so special: This eerie scene, a composite of images captured by both the James Webb Space Telescope (JWST) and the Hubble Space Telescope, features a pair of spiral galaxies with bright cores that resemble a spooky set of "blood-soaked" eyes. These galaxies grazed each other millions of years ago and are currently colliding.

That's because millions of years ago, the smaller spiral galaxy on the left, IC 2163, slowly crept behind the larger spiral galaxy on the right, NGC 2207. Because of their close encounter, the galaxies' spiral arms may have developed tiny, tail-like extensions, both between IC 2163's core and its far left arm and between the two galaxies' bright cores. Another similar extension stretches from the top of the larger spiral, which is drifting away from the eerie scene.

The two galaxies' materials may have also collided during the graze, which might explain the thick and bulging arms, including the “eyelid” regions, highlighted in bright red.

Related: 42 jaw-dropping James Webb Space Telescope images

Both galaxies are efficient star factories, producing nearly two dozen new sunlike stars each year. This star formation rate is much higher than that of the Milky Way, which produces only two or three new sunlike stars annually. And while our galaxy produces one supernova every 50 years, both of these galaxies have hosted seven known supernovas in recent decades. These supernovas may have fueled new star formation by clearing out space in the galaxy's spiral arms, thus redistributing gas and dust. Once the material cooled down, new stars could form.

This incredibly detailed image combines mid-infrared observations from JWST with ultraviolet and visible-light observations from Hubble.

The star-forming regions scattered throughout the spiral arms are represented in bright blue in the Hubble data and in pink and white in the JWST data. The areas with large groups of stars are super star clusters. Some of the bright regions might also be mini-starbursts, in which stars form at an exceptionally high rate.

What's next? Over the course of millions of years, the orbits of these galaxies will become tighter, and they will continue to swing past each other in a spectacular cosmic dance. As they inch closer to each other, they will merge into a single galaxy with reshaped arms and a single brighter core. Finally, in the next billion years or so, this eerie scene will have a single "eye."

For more sublime space images, check out our Space Photo of the Week archives.

The Martian new year begins with data from a now-defunct rover spotting what appears to be an ancient shoreline streaking through Mars' northern hemisphere. Scientists studying data sent home by China's Zhurong rover say the findings offer fresh support to the decades-old hypothesis that an ancient ocean covered the Martian north billions of years ago.

Since Zhurong landed in 2021 — in one of the largest and oldest impact basins on Mars, known as Utopia Planitia — the rover has traveled about 1.24 miles (2 kilometers) studying the geology of its surroundings in search of signs of water or ice.

By combining observations from the rover's onboard cameras and ground-penetrating radar with remote sensing data from orbiting satellites, Bo Wu at Hong Kong Polytechnic University and his colleagues spotted several water-related features around the rover's landing area. They included crater-like pitted cones, troughs, sediment channels and mud volcano formations that the team interprets as evidence of an ancient coastline.

Based on the composition of surface deposits in the area, the ocean likely existed around 3.68 billion years ago, according to a paper describing the findings, which was published in the journal Scientific Reports.

The team thinks a variety of water-related minerals such as hydrated silica started forming on the ocean bed around this time. "The water was heavily silted, forming the layering structure of the deposits," study co-author Sergey Krasilnikov of the Hong Kong Polytechnic University told Reuters.

The ocean then froze for about 10,000 to 100,000 years — a relatively short period in geologic timescales, etching out the observed coastline before drying out, roughly 260 million years later.

"The findings not only provide further evidence to support the theory of a Martian ocean but also present, for the first time, a discussion on its probable evolutionary scenario," Wu told New Scientist.

However, not everyone is convinced yet that Zhurong's data conclusively points to an ancient shoreline. Benjamin Cardenas of the Pennsylvania State University, who has studied evolution of Martian landscapes, told AFP that erosion taking place over billions of years would most certainly destroy fragile, eons-old signs of a shoreline. Wu agreed, though noting it is nevertheless possible that subsequent asteroid strikes resurfaced bits of the shoreline spotted by Zhurong.

The presence of water, a key ingredient for life as we know it, and an ancient ocean on Mars suggests the Red Planet was once capable of harboring conditions friendly toward microbial life. Scientists continue to piece together just how all that water began disappearing into space approximately 3 billion years ago. Much of its escape is known to have been accelerated by a young sun's frequent solar storms that stripped away Mars' once-thick atmosphere.

Related: Tiny photosynthetic aliens could be lurking in hidden bubbles in Mars' ice — and could soon be replicated on Earth

Scientists also think, at least some of the ocean must have disappeared underground. Data from NASA's Insight lander recently found enough water to cover Mars with an ocean between one and two kilometers deep (0.62 and 1.2 miles) had percolated into the planet's crust, where it got stored in tiny cracks and pores. While Insight did not find any evidence for Martian life, "at least we have identified a place that should, in principle, be able to sustain life," Michael Manga of the University of California, one of the study authors, said in a previous statement.

Scientists stress that incontrovertible ground truth about Mars' water history can be established only after some of the samples from the planet are brought back to Earth, where scientists can perform the kind of detailed analysis not possible with instruments onboard the rovers.

Such analyses — and answers to the decades-old mystery of disappearance of Martian water — might be possible as soon as 2031. China recently announced it has advanced its Tianwen 3 Mars sample return mission by two years, to 2028, meaning the nation could bring 500 grams (17.6 ounces) of Martian surface samples to Earth by 2031.

If the mission goes to plan, the samples could be delivered to Earth well before the joint NASA-European Space Agency Mars Sample Return (MSR) program does so. The complex U.S. MSR program is in the midst of a major overhaul after severe cost and schedule overruns made the original mission framework unaffordable. NASA is aiming to determine by the end of the year how to simplify the mission's architecture and reduce costs such that it can bring samples scooped by the car-sized Perseverance rover to Earth before 2040, agency officials said late last month.

However, the entire MSR program is likely to soon get a hard look by the President-elect Donald Trump's administration. SpaceX, whose owner Elon Musk is Trump's wealthiest supporter and is gaining influence within the federal government, is one of the seven companies that submitted a proposal to NASA outlining a simpler sample return mission plan using SpaceX's megarocket Starship. Experts say it now makes little sense to spend billions of dollars on an independent robotic sample return mission when astronauts can simply bring the samples inside Starship.

"I see a very dim future right now for MSR as an independent project managed by NASA," Casey Dreier, who is the chief of space policy at The Planetary Society, told Space.com in a recent interview.

A study about these results was published on Nov. 7 in the journal Scientific Reports.

Originally posted on Space.com.

The Lafayette meteorite is a glassy chunk of space rock about 2 inches (5 centimeters) long. It was found at Purdue University nearly a century ago, and no one knew who discovered it or where it came from. It wasn't until the 1980s that researchers discovered that the gasses trapped inside the mysterious rock matched the Martian atmosphere as measured by NASA's Viking landers, according to Purdue University.

Researchers also learned in early studies of the meteorite that its minerals had interacted with liquid water during their formation. No one knew when those minerals had formed, though. Now, a new study, published Nov. 6 in the journal Geochemical Perspectives Letters, finds that they are less than a billion years old.

"We do not think there was abundant liquid water on the surface of Mars at this time," study lead author Marissa Tremblay, an assistant professor with the Department of Earth, Atmospheric, and Planetary Sciences at Purdue University, said in a statement. "Instead, we think the water came from the melting of nearby subsurface ice called permafrost, and that the permafrost melting was caused by magmatic activity that still occurs periodically on Mars to the present day."

Related: Elon Musk said he's 'definitely going to be dead' before humans go to Mars — and you probably will be too

Tremblay and her colleagues used variations in molecules of argon within the minerals to determine the most precise age yet for the minerals' formation. They also considered the heating that the meteorite would have experienced when it flew off of Mars after an impact 11 million years ago, as well as the possible effects of its transit through space and subsequent trip through Earth's atmosphere.

Though the meteorite's precise time of arrival on Earth isn't known, researchers reported in 2022 that trace amounts of a crop fungus on the space rock's surface, combined with unconfirmed reports that a student witnessed the meteorite land during a fishing trip, suggest that the meteorite landed in 1919.

"The age could have been affected by the impact that ejected the Lafayette Meteorite from Mars, the heating Lafayette experienced during the 11 million years it was floating out in space, or the heating Lafayette experienced when it fell to Earth and burned up a little bit in Earth's atmosphere," Tremblay said. "But we were able to demonstrate that none of these things affected the age of aqueous alteration in Lafayette."

The confirmation of the date of the meteorite's interaction with liquid water doesn't just elucidate the past history of Mars. The same methods can also work on other meteorites found on Earth, or in samples brought back from missions to other planets, moons and asteroids.

"We have demonstrated a robust way to date alteration minerals in meteorites that can be applied to other meteorites and planetary bodies to understand when liquid water might have been present," Tremblay said.

Thanks to their fleeting nature, scientists have often had to rely on luck just to observe FRBs, let alone pinpoint where they come from or what causes them to behave the way they do.

Now, astronomers led by Kritti Sharma at the California Institute of Technology posit that such energy-packed light flashes tend to occur in massive, star-forming galaxies from powerful eruptions of rare, long-dead stars known as magnetars. These findings, the researchers say, also point to magnetars themselves being cosmic fusions of two stars, pinning down one potential formation pathway for the mysterious objects.

"Very little is known about what causes the formation of magnetars upon the death of massive stars," Sharma said in a recent news release. "Our work helps to answer this question."

Related: Strange radio bursts that outshine entire galaxies may come from colliding neutron stars, new study suggests

By analyzing the home galaxies of 30 FRBs recorded by California's Deep Synoptic Array-110, Sharma and her colleagues found that the bursts originated in massive, star-forming galaxies rich in "metals" — astronomer-speak for any element heavier than hydrogen and helium. Such metal-rich environments may be conducive to the formation of magnetars, which are the leading candidates for producing FRBs, according to the researchers.

Magnetars, a type of neutron star, may be the explosive remnants of stellar mergers, rather than the result of massive stars collapsing and exploding as supernovae, since the phenomena originate in different types of environments, the team suggested in a paper published Nov. 6 in the journal Nature.

Metal-rich stars that reside in pairs in such galaxies tend to become less compact as they evolve, accelerating the transfer of mass between them and effectively initiating the timeline for a stellar merger, the researchers say. The surviving star, usually the larger of the two, is rejuvenated by burning the fuel accreted from its companion, leading to amplified magnetic fields that are hundreds of trillions of times stronger than Earth's — a magnetar.

This scenario could also explain the occasional detection of FRBs in regions with old stars, as binary star systems typically live longer compared to isolated magnetars, Nature News reported.

Other questions linger about the nature of FRBs, including why a handful seem to go off multiple times a day while others flash only once.

"We have no idea what's causing them," Ayush Pandhi of the University of Toronto in Canada told Astronomy.com. "It's one of the big mysteries in astronomy right now."

Originally posted on Space.com.

Our team has now provided tentative evidence for a sulfur-rich atmosphere on a world that's 1.5 times the size of Earth and located 35 light years away. If confirmed, it would be the smallest known exoplanet with an atmosphere. The potential presence of the gases sulfur dioxide (SO₂) and hydrogen sulphide (H₂S) in this atmosphere hint at a molten or volcanic surface.

In our solar system, we have two distinct categories of planets — the small rocky ones, including Earth and Mars, and the gas giants such as Jupiter and Saturn. However, exoplanets span a great spectrum of sizes. Our solar system lacks a planet whose size falls into the range between Earth and Neptune, but it turns out that's the most common type of planet we have seen around other stars in our galaxy.

The ones closer to Neptune's size are called sub-Neptunes and the ones closer to Earth's size are called super-Earths. L 98-59 d is a super-Earth, slightly bigger and heavier than the Earth. The composition of the atmospheres of these planets is still an open question, one that we are only starting to explore with the James Webb Space Telescope (JWST), launched in 2021.

L 98-59 d was discovered in 2019 with Nasa's Tess space telescope. Most exoplanets, including L 98-59 d, have been detected using the "transit method". This measures the tiny dips in starlight when the planet passes in front of the star. This dip is more pronounced for larger planets and enables us to figure out the size of a planet.

Related: 32 alien planets that really exist

Even JWST can't separate these tiny planets from their host stars — as they orbit their stars too closely. But there is a way to "see" the planet's atmosphere from this entangled light. When a planet passes in front of its star, some of the starlight filters through a planet's atmosphere, hitting the gas molecules or atoms present there, on its way to us on Earth.

Every gas modifies the light in its own signature manner. From the light we receive from that star system, we can infer what the composition of that atmosphere might be. This is called transmission spectroscopy, a proven technique that has previously been used to confirm the presence of CO₂ in an exoplanet's atmosphere.

I am part of an international team of scientists who used JWST to observe one transit of L 98-59 d across the disc of its host star. We then obtained the transmission spectrum of the atmosphere of the exoplanet from these observations. This spectrum hinted at the possible presence of an atmosphere filled with sulfur dioxide and hydrogen sulphide.

This discovery was surprising, as it stands out in stark contrast to the atmospheres of rocky planets in our own solar system, where water vapour and carbon dioxide are much more prevalent. Earth's atmosphere, for example, is rich in nitrogen and oxygen, with trace amounts of water vapour. Meanwhile, Venus has a thick atmosphere dominated by carbon dioxide. Even Mars has a thin atmosphere dominated by carbon dioxide.

We then used computer models that incorporate our understanding of planetary atmospheres and the light coming from L 98-59 d to come up with a potential picture of the composition of this planet's atmosphere. The absence of common gases such as carbon dioxide and the presence of SO₂ and H₂S suggests an atmosphere shaped by entirely different processes to those we're familiar with in our solar system. This hints at unique and extreme conditions on L 98-59 d, such as a molten or volcanic surface.

Additional observations will be necessary to confirm the presence of these gases. JWST observations had previously spotted signs of SO₂ on an exoplanet, but this was a gas giant, not a potentially rocky world such as L 98-59 d.

Exo-volcanoes?

The potential presence of SO₂ and H₂S raises questions about their origin. One explosive possibility is volcanism driven by tidal heating, much like what is observed on Jupiter's moon Io. The gravitational pull of the host star on this planet stretches and squeezes it as it goes along its orbit. This motion can heat up the centre of the planet, melting its interiors and producing extreme volcanic eruptions and possibly even oceans of magma.

Combined with its close proximity to the star (one year on this planet is seven and half Earth days), truly hellish temperatures can be reached on the surface. If future observations support the presence of such an atmosphere, not only would it be the smallest exoplanet to have a detected atmosphere, but also a crucial step towards understanding the nature of such planets.

Detecting atmospheres on small, rocky planets is exceptionally difficult, as the planets are very small compared to the host stars, and also as intense radiation from their host stars often strips the atmospheres away. These observations, while tantalising, are only from a single transit. That means instrumental noise and other factors prevent us from making statistically strong claims. Future JWST observations will be key in confirming or refuting our analysis.

L 98-59 d may not be a candidate for life as we know it, but studying its sulfurous atmosphere and potential volcanism provides valuable insight into worlds around other stars. Extreme worlds like these help us understand the diversity of planetary evolution across the galaxy.

This edited article is republished from The Conversation under a Creative Commons license. Read the original article.

The standard model of galaxy formation predicts that only dim light should be seen from the primitive galaxies that took shape in the first billion years after the Big Bang. The unusually large and bright galaxies detected by JWST bolster predictions made by a rival theory known as modified Newtonian dynamics (MOND). The researchers published their findings Nov. 12 in The Astrophysical Journal.

"What the theory of dark matter predicted is not what we see," study lead author Stacy McGaugh, an astrophysicist at Case Western Reserve University in Ohio, said in a statement. "The bottom line is, 'I told you so.' I was raised to think that saying that was rude, but that's the whole point of the scientific method: Make predictions and then check which come true."

MOND proposes that for gravitational pulls 10 trillion times smaller than those felt on Earth's surface, such as the tugs felt between distant galaxies, Newton's laws break down and must be replaced by other equations. First proposed by Israeli physicist Mordehai Milgrom in 1982, the theory first emerged as an attempt to explain the faster-than-expected rotations seen around the outskirts of distant galaxies.

Related: Researchers spot rare 'triple-ring' galaxy that defies explanation

MOND has had a number of successes, helping to unearth unexpected laws dictating how galaxies move through space. Yet the theory remains widely rejected by astronomers, who tend to favor cold dark matter theories, because it has yet to explain a wide range of cosmological phenomena. On the other hand, dark matter theories can explain a lot of observations, but they fail to do so for those accurately predicted by MOND.

To search for clues that could break the deadlock, the astronomers pored over data collected by JWST, capturing the dim signals of some of the earliest galaxies in the universe. According to their study, these ancient galaxies had grown significantly bigger and brighter than conventional dark matter models forecast, but they are exactly in line with the predictions made by MOND.

Exactly what could be causing the discrepancy remains an exciting mystery. It's possible that the additional brightness stems from supermassive black holes that are growing significantly faster than expected, but that idea presents problems of its own.

"We find ourselves caught between two very different theories that seem irreconcilable despite applying to closely related yet incommensurate lines of evidence," the astronomers wrote in the paper. "The simple force law hypothesized by MOND has made enough successful a priori predictions that it cannot be an accident: it must be telling us something. What that is remains as mysterious as the composition of dark matter."

The enormous galaxies — each 100 billion times the mass of our sun and nearly as massive as the Milky Way — are more than 12.8 billion years old, having formed within a billion years of the Big Bang.

This means that the stars within these galaxies coalesced at a bafflingly fast rate; so fast, they challenge existing models of how galaxies form. The researchers published their findings Nov. 13 in the journal Nature.

"Finding three such massive beasts among the sample poses a tantalising puzzle," study co-author Stijn Wuyts, a professor of astronomy at the University of Bath in the U.K., said in a statement. "Many processes in galaxy evolution have a tendency to introduce a rate-limiting step in how efficiently gas can convert into stars, yet somehow these Red Monsters appear to have swiftly evaded most of these hurdles."

The conventional view among astronomers is that galaxies form within gigantic halos of dark matter, whose powerful gravity sucks ordinary matter such as gas and dust inwards before compressing it to form stars.

Related: James Webb Space Telescope is 'science and magic rolled together,' says iconic astronomer Maggie Aderin-Pocock

Typically, this is seen as a fairly inefficient process, with just 20% of the infalling gas ending up as stars. The discovery of the red monsters confounds this view, with as much of 80% of their gas seemingly converted into bright young stars.

"These results indicate that galaxies in the early Universe could form stars with unexpected efficiency," study lead author Mengyuan Xiao, a researcher at the University of Geneva, said in the statement. "As we study these galaxies in more depth, they will offer new insights into the conditions that shaped the Universe's earliest epochs. The Red Monsters are just the beginning of a new era in our exploration of the early Universe."

The red monsters, which get their nickname from their distinctive red glow, were spotted using the JWST's Near Infrared Camera (NIRCam), a spectrograph that studies distant light by splitting it into its constituent parts. The JWST's infrared capabilities enable it to peer deeper and into more dust-obscured parts of the early universe than other telescopes.

The researchers' next steps will be to make further observations of the red monsters using both the JWST and Chile's Atacama Large Millimeter Array (ALMA) telescope. The discoveries also raise questions for astrophysicists working on models of how early galaxies evolved, who may have to consider unique processes that enabled giant galaxies to grow with such efficient star formation.

"Already in its first few years of operation, JWST has thrown us a couple of curveballs," Wuyts said. "In more ways than one, it has shown us that some galaxies mature rapidly during the first chapters of cosmic history."