ancient Egyptians, it was the sacred home of Wadjet, the cobra goddess of Lower Egypt, and one of the most religiously important cities in the pharaonic landscape.

Archaeologists have excavated its upper layers for decades, finding remains from the rule of the Macedonian Ptolemaic dynasty (305 to 30 B.C.) and Roman era (30 B.C. to A.D. 395). But the deeper, older layers at the site — including a mound called Kom C, sitting below groundwater level in waterlogged delta clay — had stayed stubbornly out of reach. Kom C itself rises above the surface as a visible mound, but earlier excavations had reached only the Ptolemaic and Roman layers before hitting the water table.

Now, researchers have turned to noninvasive tools, including satellite imagery, to delve into the mysterious subterranean layers.

First, they turned to the European Space Agency's Sentinel-1 satellite, which can produce radar images by beaming down microwave pulses from orbit and then measuring how they reflect back; the returning signals can reveal subtle differences in surface moisture, elevation and reflectivity that can hint at buried structures beneath the ground. After looking at these radar images, the team spotted a large oval-shaped anomaly buried beneath Kom C that was 420 feet long and 203 feet wide (128 by 62 meters).

To learn more without disturbing the site, the team ran 15 parallel lines of electrical resistivity tomography (ERT) across an area of roughly 58,100 square feet (5,400 square meters). This technique reveals the underground landscape by passing electrical currents through the earth, measuring how they travel and creating a map that archaeologists can read.

The picture that came back was layered. Between the surface and 10 feet (3 m) down, the team found scattered Ptolemaic and Roman debris, including displaced mudbricks, pottery shards and broken limestone, which point to centuries of continued occupation and rebuilding on the site. Later residents dismantled older structures for reuse and left a scatter of displaced material behind.

Using pure sand as a stabilizing cushion was a brilliant, deliberate tactic — the ancient builders profoundly understood their environment.

Hussein Bassir, director of the Antiquities Museum at Bibliotheca Alexandrina

Deeper still, between 10 and 20 feet (3 and 6 m), the researchers found a large mudbrick structure from the 26th dynasty (688 to 525 B.C.), also known as the Saite period. They were able to date this discovery based on its layer, the unique shape of the mudbricks and other artifacts such as pottery, which the team dated by style and their archaeological layer, with carbon-14 dating applied to associated organic material. The large structure may be a tomb, a house for priests or a religious shrine, the team wrote in the study, published in March in the journal Acta Geophysica.

And below that, at 20 to 23 feet (6 to 7 m) underground, the researchers unexpectedly found a thick, clean layer of sand.

That sand is the discovery within the discovery, the team wrote in the study.

The Nile Delta's clay is notoriously treacherous to build on. It absorbs moisture and swells, and then contracts and shifts as it dries — posing a slow-motion threat to anything heavy sitting on top of it. The Saite builders, it seems, knew this. Before laying the foundations to their structure, they packed a cushion of clean sand beneath it. This sand would have spread the building's weight, let groundwater drain through, and stopped the clay from creeping. It is the same logic behind modern load-distributing foundations — applied here more than two and a half millennia ago.

"By combining satellite radar with deep ERT profiles, we didn't just map the walls of this massive Saite-era structure — we were also able to analyze the subsurface layers," study co-author author Abdelaziz Elfadaly, an associate research professor at Egypt's National Authority for Remote Sensing and Space Sciences, told Live Science. "The detection of a significant, clean sand foundation layer beneath the mudbrick walls explains how these heavy structures survived the high water table and shifting clayey soil of Buto."

The sand layer, in effect, acts as a barrier; it stops groundwater from wicking upward into the mudbrick, which would soften and dissolve it. The sand also lets water drain sideways instead of pooling against the foundation, according to Elfadaly.

A 3-by-3 foot (10 by 10 m) excavation trench that was around 20 to 23 feet (6 to 7 m) deep confirmed the presence of thick mudbrick walls resting on that sand layer, and nearby, a spread of objects that hint at the site's sacred function. According to Elfadaly, these finds included ushabti and shawabti figurines — small servant statues typically placed in tombs to serve the deceased in the afterlife — and a limestone altar whose carved channels bore dried residues consistent with animal blood, pointing to offering rituals performed at the site. The study also noted a rarer find: a faience baboon figurine, the kind associated with Thoth, the god of wisdom.

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The Saite period was a moment of cultural revival. After generations of Assyrian and Libyan domination, Egyptian pharaohs retook the throne and poured resources into restoring Egypt's religious landscape, particularly in the Nile Delta, which had been their power base. Buto, with its deep ties to Lower Egyptian identity, was a natural focus. The Saite kings ruled from the nearby delta city of Sais, so restoring Buto reinforced their roots and their claim to the throne.

"A monumental building of this scale underscores the Saite pharaohs' intense commitment to glorifying the Delta region," Hussein Bassir, director of the Antiquities Museum at a cultural research center known as Bibliotheca Alexandrina who wasn't involved with the study, told Live Science in a WhatsApp message. "Using pure sand as a stabilizing cushion was a brilliant, deliberate tactic — the ancient builders profoundly understood their environment."

The team is planning a return visit, this time using wider-spaced electrical resistivity surveys to reach deeper layers, along with specialists who study ancient plants and also understand how geological features changed over time, which may help reconstruct what the landscape around Buto looked like when these walls were first laid.

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'> Buried for 2,600 years beneath Nile mud, a massive ancient Egyptian complex was just found — from space

The idea is not new. It's been discussed in the past, but it was difficult to get a consensus on what goes in and what should not go in. That's still going to be tricky, but at least there's a broad acknowledgement that the time is ready to start introducing biology into the DSM.

It's very likely that, at the end of it, there will be meaningful changes in a positive kind of way. It's not going to make everyone happy. There are going to be gaps, but the idea is to incrementally improve this and make it more modern as we go along.

KHC: What sort of biological markers have you seen that we can actually correlate with these disorders?

AK: What the committee is doing is taking a more nuanced approach. Outside the realm of Alzheimer's disease, which I'll get into in a minute, there are no clear-cut diagnostic biomarkers — meaning no blood tests or brain scans that you can look at and say, "This person has a diagnosis of depression," or "This person has PTSD," or "This person has schizophrenia."

The committee talked about how, in addition to biological biomarkers, there's a concept of biological factors. What I mean by that is biological pathways and mechanisms that have a role in the development of a particular disorder, but the findings have not crystallized into a laboratory test.

For example, immunology — the study of the body's response to a variety of stresses, including infections and others — has been shown to be impactful in about 30% of cases of major depression. Yet there is no single biological laboratory test that is currently available that can be used [to diagnose immune-mediated depression] in clinical practice. So these come under the category of what we call biological factors.

In the Alzheimer's disease field there are clear-cut biomarkers. There are now blood tests for proteins called tau and amyloid that have been approved by the FDA [Food and Drug Administration] as biomarkers for Alzheimer's disease. Meaning, if you have a clinical picture and a mental-status exam consistent with intellectual decline, you must have a positive biomarker test to be categorized as having definitive Alzheimer's disease.

And that's new. Ten or 15 years back, there were brain scans, and if you did a lumbar puncture, you could find these proteins in the spinal fluid. But those are invasive. Now you actually have a blood test.

But that degree of precision, for lack of a better term, is not available in the other branches of psychiatry. Nonetheless, there are clues that other pathways and mechanisms are involved.

I mentioned immunology as one. Another big elephant in the room is genetics.

Most people think of genetics as an abnormal gene or a mutation — meaning a gene switches or changes and confers increased risk — as one mutation causing one disease. That's how most people in the general public think about mutations: They cause disease.

But when you get into complex diseases like heart disease and diabetes, there are multiple genes involved. And diseases may or may not be caused by a gene. Abnormal genes may or may not cause the disease, but they increase risk.

With mental disorders, the situation becomes immensely more complicated. It's not just a few genes here and there. There are hundreds of genes, each increasing the risk for depression, schizophrenia and anxiety disorders by a small amount.

So while there is no single genetic test that can now be used, large numbers of genes have consistently been shown — and many of the recent studies are strong — to be associated with certain disorders. But because there's no single gene or small group of genes, we cannot walk away from the science. Complexity doesn't mean we throw our hands up and say, "Well, it's all too much."

It may seem overwhelming, but genetic profiles are better understood today than they were 20 years ago. So that's something else this committee is thinking about and I think should take into account going forward: to somehow incorporate that into the diagnostic categories.

KHC: Do you think there's any sort of risk with adding those biological factors into the DSM?

AK: I don't think so, because if you think about genetics, it's not going to be introduced as a biological test.

Most folks know that mental disorders, like other medical disorders, run in families. And genetics is the most plausible explanation for that. What this does, I hope, is introduce a degree of more comprehensive description of these disorders. So when a busy clinician looks at it, it confirms what they already suspected: There's a family history here, and family history means genetics.

It's complex, many genes are involved, and it produces a better characterization of this. The diagnosis is still going to remain clinical, but this provides a biological context, very much like, say, diabetes or heart disease.

Genes and environment cause a variety of medical disorders. With heart disease, there's no one gene. When cardiologists develop a risk profile for heart disease, it includes genes, other physiological factors such as BMI, which is the weight-height ratio, diet and a variety of environmental factors.

That degree of classification is missing today in mental health and psychiatry. We hope this is a first step in correcting, if you will, those conceptions about what causes these disorders.

KHC: How would you end up using this in a psychiatrist's office to guide treatment?

AK: I can give you one possible example. I'm reaching a bit.

There's a term commonly used in clinical psychiatry and psychology called comorbidity. What it means is that people who are diagnosed with depression also have anxiety, or people who are diagnosed with an anxiety disorder also have substance abuse or alcoholism in general.

That is not coincidental. It's not something that we just somehow find. A lot of these disorders share genes.

For example, about 45%, roughly, of patients diagnosed with a major mood disorder also have an anxiety disorder. And you flip that around: About 45%, roughly, of patients diagnosed with an anxiety disorder — it could be generalized anxiety disorder, what we call PTSD, or a phobia — also have a mood disorder.

I think when clinicians classify them together, not as the same disorder but as sharing a lot of psychological as well as genetic risk, clinicians should be on the lookout for both. A patient with a mood disorder, for example, could either now or at some later point develop an anxiety disorder. Or someone with an anxiety disorder is at risk for substance abuse.

So treatments need to be tailored a little more broadly. I'm hoping that'll be something clinicians think about when they talk to patients and their families.

KHC: What do you think is the most unique aspect, from your perspective, of this upcoming DSM-6?

AK: My bias is the biology. I say this because a lot of the other things, the cultural factors, etc., are largely appreciated, and they'll be better characterized. Some things like cognitive changes, such as working memory and attention [tests], are not unique to any given disorder.

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Biology will be qualitatively new when introduced into the DSM, and I hope it's done well. I hope that they do it appropriately, and I think they will [do it] correctly.

It's not going to be perfect, but it's going to be a first step. I think introducing the idea that genetics, immunology and other factors are very important in the causation of mental disorders, and explain some of the phenomena that we previously could not find an explanation for, is — I hate to use the word "leapfrog" — but that's kind of what it is.

It moves the field conceptually forward, and not as a slow, steady, gradual increase. For the DSM, it would be an important step forward.

This interview has been condensed and edited lightly for clarity.

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'> 'Now you actually have a blood test': Psychiatry's bible, the DSM, is getting upgraded to include biological markers. A psychiatrist explains what...

The Lycurgus Cup is a Roman-era glass goblet that changes color from jade green to ruby red depending on if a light is shining on its front or back. But experts are unsure where the cup was found, where it was made, or whether the glassblower who made it created the color-changing effect on purpose.

In 1958, the British Museum acquired the cup from the Rothschild banking family, which had owned the artifact since the mid-19th century. Known colloquially as the Lycurgus Cup for its depiction of the mythical king who angered the god Dionysus, the glass is about 6.3 inches (15.9 centimeters) tall and weighs around 1.6 pounds (700 grams).

The glass is a remarkably well-preserved example of a Roman "cage-cup," according to a 1959 study of the artifact by archaeologists D. B. Harden and Jocelyn Toynbee. Only a handful of cage-cups still exist, and experts believe the goblets were made by cutting and grinding decoration into thick glass. Because small bridges were left to ensure the decoration remained on the glass, the overall effect is like a cage. Harden and Toynbee estimated that the Lycurgus Cup was manufactured in the fourth century, likely in Italy, but they noted that the bronze frame that forms the stem and rim of the goblet is probably a 19th-century addition.

Depicted on the cup is the myth of the punishment of Lycurgus, king of the Thracian tribe called the Edoni (also called the Edonians). Lycurgus did not approve of the worship of Dionysus and banished the god into the sea with an ax. But one of Dionysus' priestesses, Ambrosia, decided to fight Lycurgus. Ambrosia changed herself into a vine and wound herself around Lycurgus, who was unable to escape. The other priestesses thronged around them and tormented Lycurgus. Given that Dionysus was a god of wine and merriment, the depiction of Lycurgus' punishment may have been particularly appropriate for this goblet. Additionally, the change in color from green to red may have been meant to mimic the ripening of grapes on the vine.

Color-changing cups, also called dichroic cups, were mentioned in ancient Roman historical records. For example, a second-century letter possibly penned by Emperor Hadrian to his brother-in-law mentions a gift of two dichroic cups to use during banquets. But very few fragments of this mysterious type of glass survive today, a 2007 study noted.

For decades, experts have been working out how ancient Romans produced dichroic cups, and some have even replicated the Lycurgus Cup's color-changing effect. A 1963 study confirmed that the key seems to be the addition of microscopic nanoparticles of gold and silver during glassblowing that produce the appearance of milky-green glass when lit from the front and nearly translucent red glass when lit from behind. The metal nanoparticles are smaller than grains of sand and interact with light, creating the perception of a color change.

A replica of dichroic glass made by Corning Glassworks in the 1960s went from green to amethyst in the light, the 2007 study reported, and in 2020, researchers included silver and gold nanoparticles in 3D printing to replicate the color-changing properties of the glass.

More recently, experts at the University of Sheffield in the U.K. reproduced the dichroic glass by reverse-engineering the "recipe" from the original Lycurgus Cup. The team then commissioned a glass artist to create a Lycurgus-inspired design from the replica.

But because so few examples of dichroic glass exist, experts are still unsure whether Roman artisans created the color-changing effect on purpose or whether traces of gold, which would have been available in an ancient craft studio, slipped into the molten glass and made a rare and unusual material that mystified even the most skilled glassblowers.

For more stunning archaeological discoveries, check out our Astonishing Artifacts archives.

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The absence coincided with unusually warm ocean conditions during an El Niño event. Sea surface temperatures were as high as 82 degrees Fahrenheit (28 degrees Celsius), while at a depth of 330 feet (100 meters) water temperatures ranged from 66 to 67 F (18.9 to 19.4 C) — up to 9 F (5 C) warmer than usual for that time of the year.

This raised the possibility that El Niño changed where blue whales were finding food and, in turn, where they went. The researchers suspect the animals may be seeking colder, more productive waters. However, the whales themselves are still missing.

"The hypothesis is that the whales are staying in areas with greater productivity [more food] farther south, in waters with slightly cooler temperatures," Daniela Alarcón, the expedition's leader and a researcher at the Universidad San Francisco de Quito's Galápagos campus and the Galápagos Science Center, told Live Science.

As to where the missing whales have gone, possibilities include the waters off Peru and offshore areas where the animals could go undetected. In this scenario, the unusually warm waters around the Galápagos Islands would act as a "temperature barrier," Alarcón said, preventing them from feeding in the archipelago's waters.

Why water temperature matters

Blue whales (Balaenoptera musculus) can consume up to 12,100 pounds (5,500 kilograms) of krill — small crustaceans that make up the whales' primary food source — every day. That means they need to find areas with enough food to sustain them.

"These are very large animals that need to move to areas where they can keep feeding," Alarcón said.

It's not yet clear whether this year's El Niño caused a krill shortage in the waters off the Galápagos, but some indirect evidence points that way.

Past expeditions suggested that blue whales tend to feed in water layers around 71 F, which this season was identified around the Galápagos at a depth of about 197 feet (92 m). By contrast, peak chlorophyll concentrations, an indirect indicator of abundance of the krill's food source, phytoplankton ‪—‬ were recorded much higher in the water column, at between 39 and 121 feet (12 to 37 m) below the surface. Because krill abundance wasn't directly measured, that data suggests, but does not establish, that there was a mismatch between the whales' preferred feeding layer and the presence of their food.

"Honestly, we had never encountered such unusual conditions before," Juan Pablo Muñoz, a marine biologist at the Universidad San Francisco de Quito who was also on the expedition, told Live Science.

Continuation of a trend

The whales' absence did not come as a complete surprise to the team. Sightings had already begun to decline before the most recent expedition. Reports submitted through Cetácea Galápagos, a citizen science network, began to dwindle between August and September 2025. There were two isolated reports of blue whales, in May and June 2026, but the team could not confirm either one, despite intensifying its search.

"We knew conditions wouldn't be the same, but we thought that if we put in more effort, we might be able to find some individuals. But we searched, and searched, and searched — and found nothing," Alarcón recalled.

Part of that could be down to the elusive nature of the giant creatures. Humpback whales (Megaptera novaeangliae)are generally easier to spot, Muñoz noted. In some places, they can be seen from the shore or after a half-hour boat ride. Blue whales, by contrast, rarely approach mainland Ecuador's coast and tend to stay far from populated areas in the Galápagos.

Sensitive to temperature fluctuations

Fernando Félix, a marine biologist at the Pontifical Catholic University of Ecuador who was not part of the expedition, was unsurprised by the result.

"We already knew there wouldn't be any blue whales in the Galápagos," said Félix, who is also a researcher at the Whale Museum (Museo de Ballenas).

Félix told Live Science that there are historical precedents for this behavior in the southeastern Pacific. During the 1982-1983 El Niño, which also brought substantial ocean warming, blue whales and other species, including fin whales (Balaenoptera physalus) and Bryde's whales (Balaenoptera brydei), were recorded shifting southward.

"We might think that because they are 'just animals,' they lack memory or don't understand these processes — but we would be wrong," Félix said. "They can clearly sense that when temperatures are unusually high as they travel north from the south, vertical mixing has been disrupted and there is no food in the Galápagos. They perceive environmental conditions and naturally direct their movements toward areas where they believe feeding conditions are better."

Rather than indicating a mass die-off, the whales' disappearance may reflect a shift in their movements in response to changing ocean conditions, Félix said.

"I don't think the whales have died," Felix said. "They simply didn't go to the Galápagos region. They went elsewhere, where conditions were better."

This response to environmental conditions may also have impacted dolphin movements. Pods may have moved toward colder waters, where food could be more abundant, or may have even dispersed, Félix suggested.

When will blue whales return to the Galápagos?

El Niño's effects will likely persist over the coming months. "Between January and May 2027, we'll have warm water coming from the north and warm water coming from the west," Félix warned. "This is going to hit us extremely hard."

Blue whales, humpback whales and dolphins would likely return to Galápagos waters once El Niño subsides and ocean conditions begin to normalize. He said pelagic fish (species that live in the water column rather than on or near the seafloor) ‪—‬ including tuna, swordfish, anchovies and sardines, which have also moved toward colder waters ‪—‬ would return as well.

Muñoz agreed. Krill populations can rebound just one to three months after cold, nutrient-rich waters begin to rise to the surface. More whale sightings were recorded in the years following the 2015 and 2023 El Niño events. Based on these precedents, he suggested that 2028 could be a promising year if cold water returns to the surface. "The system bounces back," he said.

Félix compared El Niño to a computer restart. "It resets the environment, allowing ecological processes to begin again," he said. He's confident that blue whales will return to the area. "I can guarantee that there will be large numbers of blue whales at this time in 2028," he told Live Science.

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Rising from the cloudy Carina Nebula some 7,500 light-years from Earth, the Cat's Head Nebula is a column of star-sculpted gas and dust that vaguely resembles a feline sitting with its back to us, coyly turning its head to show off a single red eye. That eye is a young star that's embedded deep within the dust and possibly transforming it before our eyes.

Nebulas like these occur when the radiation from active young stars lights up and erodes the material around them. They are beautiful and easy to find; if this cosmic cat gets bored staring at us, it can just waltz over to the other side of the Carina Nebula and crawl into a similar globule of gas that looks exactly like a box with an open lid. (Cats will be cats, after all.)

In honor of Halloween, the European Space Agency (ESA) shared three competing views of the Cat's Head Nebula — one from the Hubble Space Telescope, which captures optical light, and two from the infrared instruments aboard the James Webb Space Telescope (JWST). The three views, shown below, reveal different features of the nebula in different wavelengths of light, getting progressively spookier as more color drains out of the scene.Take a look at all three images — and cast your vote for the spookiest in the poll at the end.

Hubble's view

Observing the nebula in the same visible wavelength range that you could see through a strong backyard telescope, Hubble highlights the dark pillar of dust that has survived the ultraviolet assault of nearby stars. The wispy edges at the right of the column show where starlight is evaporating the gas around it, slowly whittling it away to nothing.

The glow of blue, yellow, orange and red light around the dust pillar mark where starlight is interacting with different gas molecules, including oxygen, hydrogen and sulfur, according to ESA. The process is similar to how different molecules in Earth's atmosphere produce different-colored auroras when excited by solar radiation — just on a much grander scale.

JWST's near-infrared view

Switching to light human eyes cannot see, JWST's Near-Infrared Camera cuts through the wispier outer layers of dust to show the densest material at the column's center. Countless additional stars and galaxies appear in the field of view as their infrared glow penetrates the surrounding material.

Here we see a more complex, turbulent column, showing how stellar radiation is carving up the inside of the cat's head as well as its edges. JWST's view also illuminates a disembodied, hand-like structure to the left of the cat, reaching out as if to pet its cosmic companion.

JWST's mid-infrared view

The final view, taken with JWST's Mid-Infrared Instrument, cuts to the ghostly core of the nebula, showing little more than smoky, bluish light. According to ESA, these are the emissions of molecules called polycyclic aromatic hydrocarbons — typically colorless molecules of carbon and hydrogen related to combustion.

While most starlight disappears in this view, a strange new bright spot emerges to the right of the cat's head. This orange speck is a true mystery, according to ESA, and its relationship to the rest of the nebula is unknown.