Shift in key cosmic inflation measurement could be a statistical artifact

For the last few decades, researchers have been studying what the universe looked like in its first seconds. It is generally accepted that the universe expanded exponentially in the first fraction of a second after the Big Bang. Researchers use ns, the scalar spectral index, to characterize how primordial density fluctuations were distributed across different length scales in the early universe. The value of ns is a central observable in inflationary cosmology, since different inflationary scenarios predict distinct values for this quantity, making it a powerful discriminator between models.

Why cultivating drought-resistant plants disappoints: Soil physics may be the real bottleneck

Plants need water, light, and air to thrive. But when they transport water from the soil up to their leaves, they defy gravity. Scientists describe this astonishing phenomenon as “negative water potential,” a form of negative tension that enables herbs, shrubs, and trees to draw water from the soil. Nevertheless, plants do not constantly extract water from the soil. For decades, researchers have sought to understand what limits a plant’s water uptake.

Astronomers discover 87 stellar stream candidates in the Milky Way

Stellar streams are trails of stars that astronomers can study to solve mysteries about the history of our Milky Way galaxy and, potentially, the dark matter that helps shape the cosmos despite eluding direct observation. These streams have largely been left behind by small dwarf galaxies and globular clusters, which have since petered out of existence. But there is a rare and important third type of stellar stream: streams from globular clusters that still survive.

Stealth superstorms reveal lightning on Jupiter: Beyond the superbolt

Jupiter’s lightning has long been of interest to planetary scientists, as it marks stormy spots where researchers can look to learn more about convection in Jupiter’s atmosphere. Observing lightning from a distance can be tricky, so scientists have focused on the bolts that are easiest to study: strong flashes that strike at night. As a result, some studies have concluded that lightning bolts on Jupiter are all similar to the strongest lightning on Earth, known as “superbolts.” This conclusion was recently questioned, however, when the high-sensitivity star tracker camera on NASA’s Juno spacecraft detected faint, shallow lightning.

Hubble revisits Crab Nebula to track 25 years of expansion

Nearly a millennium ago, astronomers witnessed a brilliant new star blazing in the sky—a supernova so bright it was visible in daylight for weeks. Today, its expanding remnant, the Crab Nebula, continues to evolve 6,500 light-years away. First linked to historical records by Edwin Hubble, the nebula has since been studied in exquisite detail by the NASA/ESA Hubble Space Telescope, which has now revisited this ancient explosion to trace its ongoing expansion and transformation.

‘Space archaeology’ reveals first dynamic history of a giant spiral galaxy

A team of astronomers led by the Center for Astrophysics | Harvard and Smithsonian have for the first time used galactic archaeology, the study of detailed chemical fingerprints in deep space, to trace the history of a galaxy outside the Milky Way. The study, published in Nature Astronomy, demonstrates a new way to reconstruct the evolution of distant galaxies, and opens up a new field of astronomy, called “extragalactic archaeology.”

China’s earliest Bronze Age meteoritic iron artifact unearthed at Sanxingdui sacrificial site

In a study published in Archaeological Research in Asia, Dr. Haichao Li and a team of researchers analyzed the earliest Bronze Age meteoritic iron artifact from southwestern China, the largest found to date in the country. Recovered from the famous Sanxingdui site, it provides crucial insights into the region’s metallurgical practices and fills a critical gap in the area’s metallurgical record.

Moons orbiting wandering exoplanets could be habitable—with one catch

Provided they host thick, hydrogen-dominated atmospheres, moons orbiting free-floating exoplanets could retain much of the heat generated deep within their interiors by tidal forces. Led by David Dahlbüdding at the Max Planck Institute for Extraterrestrial Physics and Giulia Roccetti at the European Space Agency, a new study predicts that hydrogen could act as a potent greenhouse gas—potentially providing habitable conditions for billions of years after their host planets are first ejected from their stellar systems. The work has been published in Monthly Notices of the Royal Astronomical Society.

A self-sufficient Mars garden? How cyanobacteria-based fertilizer could grow edible biomass

A research team from the Center for Applied Space Technology and Microgravity (ZARM), the Department of Environmental Process Engineering (UVT) at the University of Bremen and the German Aerospace Center (DLR) has made significant progress toward a self-sufficient Mars mission: a fertilizer, which can be produced solely with Martian resources, has been successfully used to grow edible biomass.

ShadowCam search casts doubt on abundant lunar ice

New observations by a team of US astronomers have cast fresh doubt on whether the lunar surface could host abundant water ice. Publishing their results in Science Advances, a team led by Shuai Li at the University of Hawaii at Manoa has shown that relatively pure ice (making up more than about 20–30% of the surface material) is likely absent from the moon’s permanently shadowed regions.

What ‘Project Hail Mary’ gets right—and wrong—about astrophysics

“Project Hail Mary,” the Ryan Gosling-led adaptation of the best-selling sci-fi novel from Andy Weir, is being praised for putting the science in science fiction. Although aliens, sun-draining microorganisms and galaxy-spanning spaceflight are all a part of the story of a scientist sent on a suicide mission to save Earth, the film and its source material are not afraid to delve into the kind of astrophysics that would make most people’s heads spin.

ALICE sees new sign of primordial plasma in proton collisions

The ALICE Collaboration takes a step further in addressing the question of whether a quark–gluon plasma can be formed in proton–proton and proton–nucleus collisions. In the first few microseconds after the Big Bang, the universe was in an extremely hot and dense state of matter known as quark–gluon plasma (QGP), which can be reproduced with high-energy collisions between heavy ions such as lead nuclei.