The second wet dress rehearsal for the Artemis II mission continues as teams power up the rocket’s core stage — which contains propellant tanks — and charge the Orion spacecraft’s flight batteries.

Tomorrow, teams will practice fueling the rocket. go.nasa.gov/4qIwL40

A new technology developed at NASA’s Jet Propulsion Laboratory in Southern California enables Perseverance to figure out its whereabouts without calling humans for help. Dubbed Mars Global Localization, the technology features an algorithm that rapidly compares panoramic images from the rover’s navigation cameras with onboard orbital terrain maps. Running on a powerful processor that Perseverance originally used to communicate with the Ingenuity Mars Helicopter, the algorithm takes about two minutes to pinpoint the rover’s location within some 10 inches (25 centimeters). Mars Global Localization was first used successfully in regular mission operations on Feb. 2, then again Feb. 16.

“This is kind of like giving the rover GPS. Now it can determine its own location on Mars,” said JPL’s Vandi Verma, chief engineer of robotics operations for the mission. “It means the rover will be able to drive for much longer distances autonomously, so we’ll explore more of the planet and get more science. And it could be used by almost any other rover traveling fast and far.”

The upgrade is especially valuable given how well Perseverance’s auto-navigation self-driving system has been working. Enabling the rover to re-plan its path around obstacles en route to a preestablished destination, AutoNav has proved so capable that the distance Perseverance can drive without instructions from Earth is largely limited by the rover’s uncertainty about its whereabouts. Now that it can stop and determine its exact location, Perseverance can be commanded to drive to potentially unlimited distances without calling home.

Implementation of Mars Global Localization comes on the heels of another innovation from the Perseverance team: the first use of generative artificial intelligence to help plan a drive route by selecting waypoints for the rover, which are normally chosen by human rover operators. Both technologies enable Perseverance to travel farther and faster while minimizing team workload.

Beyond visual odometry
Unlike on Earth, there is no network of GPS satellites in deep space to locate spacecraft on planetary surfaces. So missions — whether robotic or crewed — must come up with other ways to determine their location.

As with NASA’s previous Mars rovers, Perseverance tracks its position using what’s called visual odometry, analyzing geologic features in camera images taken every few feet while accounting for wheel slippage. But as tiny errors in the process add up over the course of each drive, the rover becomes increasingly unsure about its exact location. On long drives, the rover’s sense of its position can be off by more than 100 feet (up to 35 meters). Believing it may be too close to hazardous terrain, Perseverance may prematurely end its drive and wait for instructions from Earth.

“Humans have to tell it, ‘You’re not lost, you’re safe. Keep going,’” Verma said. “We knew if we addressed this problem, the rover could travel much farther every day.” After each drive comes to a halt, the rover sends a 360-degree panorama to Earth, where mapping experts match the imagery with shots from NASA’s Mars Reconnaissance Orbiter (MRO). The team then sends the rover its location and instructions for its next drive. That process can take a day or more, but with Mars Global Localization, the rover is able to compare the images itself, determine its location, and roll ahead on its preplanned route.

How Ingenuity helped
Key to Mars Global Localization is the rover’s Helicopter Base Station (HBS), which Perseverance used to communicate with the now-retired Ingenuity Mars Helicopter. Equipped with a commercial processor that powered many consumer smartphones in the mid-2010s, the HBS runs more than 100 times faster than the rover’s two main computers, which, built to survive the radiation-heavy Martian environment, are based on hardware introduced in 1997...

Scientists have created a three-dimensional "heart-on-a-chip" (HOC) that could provide a breakthrough in the fight against the world's leading cause of death, cardiovascular disease.

One major challenge is that we cannot easily test how a human heart will react to a drug or disease without putting someone at risk. This engineered heart tissue beats on its own, it mobilizes calcium to initiate muscular activity, and it responds predictably to common drugs.

It's the first to incorporate a dual-sensing platform that provides real-time tracking of activity throughout the heart tissue down to the cellular level.

In a recent paper, scientists from multiple Canadian institutions describe how they achieved this "significant advance in cardiac tissue engineering and pharmacological testing."

The key advance here is the integration of sensors that can detect both macro-scale and micro-scale cardiac activity. Both current HOC platforms and the research team's previous iteration, described in a 2024 paper, lack high-resolution cellular-level sensing.

For years, scientists have agreed on a broad explanation for how complex life first appeared on Earth, yet one critical question remained unanswered. Plants, animals, and fungi, collectively known as eukaryotes, are thought to have emerged when two very different microbes joined forces. One depended on oxygen to survive, while the other was believed to live only in oxygen-free environments. What puzzled researchers was how these two organisms could have encountered each other in the first place.

A new study from The University of Texas at Austin, published today (February 18) in the journal Nature, offers a compelling answer. Researchers focused on a group of microbes called Asgard archaea, widely considered close relatives of the ancestors of complex life. Although most known Asgard archaea inhabit deep-sea, oxygen-free settings, the team discovered that some members of this group can tolerate or even use oxygen. This finding strengthens the theory that complex life evolved in oxygen-rich conditions.

“Most Asgards alive today have been found in environments without oxygen,” explained Brett Baker an associate professor of marine science and integrative biology at UT. “But it turns out that the ones most closely related to eukaryotes live in places with oxygen, such as shallow coastal sediments and floating in the water column, and they have a lot of metabolic pathways that use oxygen. That suggests that our eukaryotic ancestor likely had these processes, too.”

The gut microbiome, also called the gut flora, is essential to human health. This vast and constantly changing community of microorganisms depends on a web of chemical exchanges. Microbes communicate not only with one another but also with the human body that hosts them. To function properly, gut bacteria must detect nutrients and signaling molecules in their surroundings. However, scientists still do not fully understand the wide range of chemical signals that bacterial receptors are able to recognize.

A key question remains: which of these signals are most important for beneficial gut bacteria?

Moving Beyond Pathogens in Bacterial Research
Most research on bacterial sensing has focused on model organisms, particularly disease-causing microbes. Far less attention has been given to commensals, the non-pathogenic and often beneficial bacteria that naturally live in humans. This has left an important gap in understanding what kinds of chemical signals these helpful microbes actually detect in the gut.

An international team led by Victor Sourjik sought to answer that question. The researchers, from the Max Planck Institute for Terrestrial Microbiology, the University of Ohio, and Philipps-University Marburg, investigated Clostridia. These motile bacteria are abundant in the intestinal flora and play a major role in maintaining gut health.

Gut Bacteria Recognize a Wide Range of Nutrients
The team found that receptors from bacteria in the human gut microbiome respond to a surprisingly broad range of metabolic compounds. These include breakdown products of carbohydrates, fats, proteins, DNA, and amines. Through systematic screening, the scientists observed that different types of bacterial sensors show clear preferences for specific classes of chemicals.

This indicates that gut bacteria are selectively tuned to certain metabolic signals rather than reacting randomly to everything in their environment.

In the BioAsteroid project, University of Edinburgh’s Professor Charles Cockell and his colleagues used the bacterial species Sphingomonas desiccabilis and the fungus species Penicillium simplicissimum to see which elements could potentially be extracted from L-chondrite asteroidal material.

But understanding how the microbes interact with rocks in microgravity was equally important.

“This is probably the first experiment of its kind on the International Space Station on meteorite,” said Dr. Rosa Santomartino, a researcher at Cornell University and the University of Edinburgh.

“We wanted to keep the approach tailored in a way, but also general to increase its impact.”

“These are two completely different species, and they will extract different things.”

“So, we wanted to understand how and what, but keep the results relevant for a broader perspective, because not much is known about the mechanisms that influence microbial behavior in space.”

People cannot survive without lungs. Yet one of Ankit Bharat’s patients did so for two full days.

In a study published in the Cell Press journal Med, surgeons detailed how they extracted a patient’s severely infected lungs and relied on a custom-built “artificial lungs” setup to sustain him until donor organs became available. The team describes the strategy as a potential bridge to transplantation for patients who would otherwise die waiting.

“He was critically ill. His heart stopped as soon as he arrived. We had to perform CPR,” recalls Bharat, the lead author and a thoracic surgeon at Northwestern University. “When the infection is so severe that the lungs are melting, they’re irrecoverably damaged. That’s when patients die.”

Joshi is the author of a new report, released Monday with support from several environmental organizations, that attempts to quantify some of the most high-profile claims made about how AI will save the planet. The report looks at more than claims made by tech companies, energy associations, and others about how "AI will serve as a net climate benefit.” Joshi’s analysis finds that just a quarter of those claims were backed up by academic research, while more than a third did not publicly cite any evidence at all.

“People make assertions about the kind of societal impacts of AI and the effects on the energy system—those assertions often lack rigor,” says Jon Koomey, an energy and technology researcher who was not involved in Joshi’s report. “It's important not to take self-interested claims at face value. Some of those claims may be true, but you have to be very careful. I think there's a lot of people who make these statements without much support.”

Another important topic the report explores is what kind of AI, exactly, tech companies are talking about when they talk about AI saving the planet. Many types of AI are less energy-intensive than the generative, consumer-focused models that have dominated headlines in recent years, which require massive amounts of compute—and power—to train and operate. Machine learning has been a staple of many scientific disciplines for decades. But it’s large-scale generative AI—especially tools like ChatGPT, Claude, and Google Gemini—that are the public focus of much of tech companies’ infrastructure buildout. Joshi’s analysis found that nearly all of the claims he examined conflated more traditional, less energy-intensive forms of AI with the consumer-focused generative AI that is driving much of the buildout of data centers.

Preliminary analysis suggests CDG-2 has the luminosity of roughly 6 million sun-like stars, with the globular clusters accounting for 16% of its visible content. Remarkably, 99% of its mass, which includes both visible matter and dark matter, appears to be dark matter. Much of its normal matter to enable star formation—primarily hydrogen gas—was likely stripped away by gravitational interactions with other galaxies inside the Perseus cluster.

Just how small can a QR code be? Small enough that it can only be recognized with an electron microscope. A research team at TU Wien, working together with the data storage technology company Cerabyte, has now demonstrated exactly that. The QR code covers an area of just 1.98 square micrometers—smaller than most bacteria. The record has now been verified and officially entered into the Guinness World Records.

The technology has enormous potential for long-term data storage: Conventional magnetic or electronic data storage systems often have lifespans of only a few years. But if information is written bit by bit into ceramic materials, it can endure for centuries or even millennia.

People who live high in the mountains have long been observed to develop diabetes less often than those at sea level. Scientists have known about this pattern for years, but the biological reason behind it has remained unclear.

Researchers at Gladstone Institutes now believe they have uncovered the answer. Their findings show that in low oxygen environments, red blood cells begin absorbing large amounts of glucose from the bloodstream, effectively acting like sugar sponges.

In a study published today (February 19) in the journal Cell Metabolism, the team demonstrated that red blood cells can reprogram their metabolism under low oxygen conditions. At high altitude, this shift helps the cells deliver oxygen more effectively throughout the body. At the same time, it reduces the amount of sugar circulating in the blood.

John Glenn, the first American to orbit the Earth, made history 64 years ago on Feb 20, 1962, with his 5-hour spaceflight.

Despite a few problems with the Friendship 7 spacecraft, Glenn made 3 orbits (2 of them manually controlled), and splashed down in the Atlantic Ocean.

Some bacterial species possess an astonishing ability: They use Earth's magnetic field to orient themselves. To better understand this mechanism, the team led by Argovia-Professor Martino Poggio from the Swiss Nanoscience Institute and the Department of Physics at the University of Basel took a closer look at the "magnetotactic" bacterium Magnetospirillum gryphiswaldense.

Inside this bacterium is a chain of magnetic nanoparticles known as magnetosomes. These act like a biological compass and allow the bacterium to align with Earth's magnetic field.

In their natural habitat, bodies of water or moist sediments, this compass helps the bacteria to advance in a systematic manner when searching for the optimal living conditions. Without this orientation, their movements would be more random, requiring greater time and energy to locate optimal oxygen levels, for example.

The potential applications of these bacteria are considerable. For instance, they could be used in medicine as magnetically controllable "microrobots" for the targeted delivery of drugs. They could also be applied in wastewater treatment, with bacteria absorbing heavy metals and then being easily removed from the water using a magnet.

A nanodevice developed at EPFL produces an autonomous, stable current from evaporating saltwater by using heat and light to control the movement of ions and electrons. Previously, researchers in the Laboratory of Nanoscience for Energy Technology (LNET) in EPFL's School of Engineering reported a platform for studying the hydrovoltaic (HV) effect—a phenomenon that allows electricity to be harvested when fluid is passed over the charged surface of a nanodevice. Their platform consisted of a hexagonal network of silicon nanopillars, the space between which created channels for evaporating fluid samples.

Now the LNET team, led by Giulia Tagliabue, has developed this platform into a hydrovoltaic system with a power output that matches or exceeds similar technologies—with a major advantage. Instead of relying on heat and light to simply boost evaporation, the EPFL system generates current by harnessing heat and light to control the movement of ions in evaporating saltwater, and the flow of electrons in the silicon nanodevice.

"Heat and light imbalances will always affect a hydrovoltaic device, but we have discovered how these can be leveraged to our advantage," explains LNET researcher Tarique Anwar.

With three distinct layers dedicated to evaporation, ion transport, and electrical charge collection, the nanodevice's decoupled design allows the scientists to observe and finely tune each step in the process. 

The researchers believe their innovation will accelerate the development of hydrovoltaic devices, which have great potential to power battery-free small sensor networks wherever water, heat, and sunlight are available. Examples include self-powered environmental monitoring systems, wearable devices, and internet-of-things applications.

There are estimated to be between one and six million species of fungi. Take a moment to appreciate a few. 🍄

Most origin-of-life scenarios focus on environments such as drying and rewetting surfaces on land or hydrothermal vents on the ocean floor. This study suggests that icy regions could also have been significant. On the early Earth, freeze/thaw cycles likely occurred repeatedly over long timescales.

Scientists at Monash University, working with Harvard University, report they have found a way to permanently ‘switch off’ genes that help cancers survive. If the approach holds up in further testing, it could point to a new style of treatment that works with shorter courses and fewer of the harsh side effects that often come with long, continuous cancer therapy.

The team described the work in Nature Cell Biology. Their focus is epigenetic therapy, which aims to change how genes behave rather than rewriting the genes themselves. You can think of epigenetics as the cell’s operating instructions for when to read a gene and when to keep it quiet. Cancer mutations can corrupt those instructions, locking dangerous growth programs in the “on” position.

Intermittent fasting – periods of eating little or nothing interspersed with normal food consumption – isn't an effective way to lose weight, according to a review of 22 randomized controlled trials. It seems that assurances from celebrity weight-loss gurus and appeals to historical precedent aren’t enough make a practice work.

Religions have encouraged or directed their adherents to refrain from eating, and in some cases even drinking water, to mark holy days or show penitence for thousands of years. In recent times, social media has been filled with those who advocate engaging in fasts for weight loss instead. The fact the practice has been so widespread for so long has been touted as evidence of its effectiveness. Until recently, however, most fasts were conducted in a world where calories were harder to come by the rest of the time, and whatever people's reasons for fasting, shedding fat wasn't high among them.

The COVID-19 pandemic highlighted just how differently people can respond to the same infection. Some individuals experience mild symptoms, while others become severely ill. This striking contrast raises an important question. Why would two people infected by the same pathogen have such different outcomes?

Much of the answer lies in differences in genetics (the genes you inherit) and life experience (your environmental, infection, and vaccination history). These influences shape our cells through subtle molecular modifications known as epigenetic changes. These changes do not alter the DNA sequence itself. Instead, they control whether specific genes are turned “on” or “off,” helping determine how cells behave and function.

Researchers at the Salk Institute have introduced a comprehensive epigenetic catalog that separates the effects of inherited genetics from those of life experiences across multiple immune cell types. This new cell type-specific database, published in Nature Genetics on January 27, 2026, provides insight into why immune responses vary from person to person and could help guide the development of more precise, personalized treatments.

The Space Station rarely makes big changes to its orientation, but we were lucky to experience such maneuvers (flipping around to fly butt-first, then flipping back again) before and after each spacex CRS-33 reboost. This 60x speed timelapse was one of my favorites since it captures a little of everything - sunset, lightning storms, air glow, moon glint, stars, and sunrise - as we did one (actually very slow) orbital cartwheel from Atlantic to Pacific.