Royer, JY., Olive, JA., Bazin, S. et al. Anatomy of a seafloor spreading event captured by in situ seismogeodesy. Nature, July 2026.
For billions of years, new ocean floor has formed where Earth’s tectonic plates slowly pull apart beneath the sea. Although scientists have long understood this process, they had never watched an entire seafloor spreading event unfold in real time. That changed when a network of underwater sensors happened to be in place as a major event occurred deep beneath the Southeast Indian Ridge.
On April 26, 2024, the instruments recorded earthquakes racing along the ridge as molten rock forced its way through cracks beneath the seafloor. As magma drained from an underground reservoir, the seafloor sank by more than four meters—most of it within the first 16 hours—while the ground stretched sideways by more than a meter. By comparing detailed maps taken before and after the event, researchers estimated that up to 160 million cubic meters of lava erupted over about 16 days, creating new ocean crust.
One of the study’s most surprising findings was that much of the movement occurred silently, without producing noticeable earthquakes. The researchers estimate that roughly three-quarters of the fault movement happened this way. Altogether, the event released an amount of strain that would normally build up over nearly 40 years as the tectonic plates slowly drift apart.
This study provides the clearest picture yet of how new seafloor is created. It suggests that the ocean floor grows not through steady, continuous movement, but through brief, dramatic bursts separated by long quiet periods. The findings also help explain why mid-ocean ridges produce fewer earthquakes than expected. Although some conclusions rely on computer models and measurements collected in a challenging underwater environment, the research offers an unprecedented glimpse into one of the Earth’s most fundamental geological processes.
Escaping Helium Offers Clues to a Distant Atmosphere
C. Cherubim et al. Helium escaping from the atmosphere of a nearby rocky exoplanet orbiting in a habitable zone. Science, July 2026.
Rocky planets beyond our solar system are notoriously difficult to study, especially when scientists try to determine whether they have atmospheres. Many orbit small red dwarf stars, whose intense high-energy radiation can gradually strip gases away. Now, researchers have detected evidence of helium escaping from LHS 1140b, a rocky planet about 15 parsecs from Earth that orbits within its star’s habitable zone, where temperatures could potentially allow liquid water under suitable conditions.
Using a high-resolution infrared spectrograph in Chile, the team observed LHS 1140b as it passed in front of its star in September 2024. Starlight filtering through the planet’s surroundings revealed a distinctive helium signal. The absorption extended beyond the planet itself, suggesting helium was flowing away from its upper atmosphere and may even form a tail along its orbit. Computer models indicate that this escaping gas is strongly depleted in hydrogen and that high-energy radiation from the star is probably driving the loss.
Intriguingly, when researchers observed the planet again in 2025, the helium signal was no longer detectable. This does not necessarily mean the escape had stopped. Changes in the star’s radiation or the temperature of the planet’s upper atmosphere could have weakened the signal below the instruments’ detection limit.
The finding offers rare evidence that a rocky planet in a habitable zone can retain an atmosphere while still losing part of it to space. It does not show that LHS 1140b is habitable, but it provides a valuable glimpse into how rocky planets and their atmospheres change over billions of years.
The Black Hole at the Center of the Milky Way
Andrea Ghez. Peering through dust clouds to the center of the galaxy. Science Friday, July 2026.
For decades, astronomers suspected that something extraordinarily massive lay at the center of the Milky Way, but dense clouds of interstellar dust made the region difficult to observe. Astronomer Andrea Ghez and her team helped solve the mystery by using powerful telescopes and new imaging techniques to track stars moving around the hidden center of our galaxy.
Rather than trying to see the object itself, the researchers followed the motion of nearby stars and used their orbits to measure the gravity acting on them. Over years of observations, the stars were seen moving rapidly and curving around a common point. Eventually, complete stellar orbits showed that roughly four million times the mass of the Sun is concentrated within a region about the size of our solar system. No alternative explanation currently accounts for such an enormous amount of mass packed into such a small space, providing compelling evidence for a supermassive black hole at the Milky Way’s center.
The discovery did more than confirm the existence of this enormous object. It gave astronomers a unique laboratory for testing gravity under extreme conditions and investigating how supermassive black holes and galaxies develop together. Scientists now think the growth of galaxies and their central black holes may be closely connected.
Important questions remain. Astronomers can infer the black hole’s presence from its gravitational effects, but current observations do not probe scales small enough to provide the ultimate direct test. More fundamentally, black holes expose a major gap in physics: Einstein’s theory of gravity and quantum mechanics still cannot be fully reconciled. Future telescopes may bring scientists closer to understanding what these mysterious objects truly are.
