It’s true that there are a lot of different theoretical proposals that serve as alternatives or extensions to mainstream physics: string theory, supersymmetry, Gauss-Bonnet gravity, GUTs, and much more. 

Many point to the success of our standard picture of reality, based on Einstein’s general relativity and the quantum field theory of the Standard Model, and (prematurely) dismiss all such alternative explorations. 

However, a tremendous amount of progress has been made simply by constraining and ruling out many such alternatives and extensions through data-driven experiments and observations. That progress is underappreciated, representing a huge achievement whenever it occurs.

Ever since their discovery more than 165 years ago, massive fossilized structures left by an organism known as Prototaxites have proven impossible to categorize.

Researchers in the UK have suggested in a recently published study that there's a very good reason these oddities don't fit neatly on the tree of life – they belong to a branch all of their own, with no modern equivalent.

Some 400 million years ago, the swamps of the late Silurian period would have sprouted a mix of horsetails, ferns, and other prototype plants that look positively alien today.

Among them stretched 8-meter (26-foot) tall towers that defy easy identification. Wide and branchless, these organisms may have been a form of algae or ancient conifer, researchers suspect, based on what little evidence remains.

Loud and clear: Curiosity and Perseverance are both back in touch with Earth following solar conjunction. They’re beginning to downlink data collected while the Sun was blocking the signal path between us and the Red Planet.

Keep up with the latest at science.nasa.gov/mars/

The phrase “House of Cards” is often associated today with a Netflix political drama, but its original meaning refers to a structure that is inherently unstable. That idea is exactly how Sarah Thiele, who began this work as a PhD student at the University of British Columbia and is now at Princeton, and her co-authors describe today’s satellite mega constellation system in a new study released as a preprint on arXiv.

Their choice of words is supported by the numbers. Across all Low-Earth Orbit mega constellations, calculations show that a “close approach”, defined as two satellites passing within less than 1 kilometer of each other, happens about once every 22 seconds. For Starlink alone, such encounters occur roughly every 11 minutes. In addition, each of Starlink’s thousands of satellites must carry out an average of 41 maneuvers each year to avoid collisions with other objects in orbit.

At first glance, this may look like a carefully managed system functioning as intended. But engineers know that “edge cases”, events that fall outside normal operating conditions, are often what trigger major failures. According to the paper, solar storms represent one such edge case for satellite mega constellations. Under typical conditions, solar storms disrupt satellite operations in two main ways.

Days away from irreversible collisions
According to their calculations, as of June 2025, if satellite operators were to lose their ability to send commands for avoidance maneuvers, there would be a catastrophic collision in around 2.8 days. Compare that to the 121 days that they calculated would have been the case in 2018, before the megaconstellation era, and you can see why they are concerned. Perhaps even more disturbingly, if operators lose control for even just 24 hours, there’s a 30% chance of a catastrophic collision that could act as the seed case for the decades-long process of Kessler syndrome.

Tomorrow marks 40 years since Voyager 2 made its closest approach to Uranus. It remains humanity's first and only spacecraft to have flown by the 7th planet from our Sun.

Voyager 2 discovered 10 moons, and examined Uranus's ring system, discovering two new rings.

For every US$1 the world invests in protecting nature, it spends US$30 on destroying it. This stark imbalance is the central finding of a new UN Environment Program (UNEP) report released today. It calls for a major shift in global financing of nature-based solutions and phasing out harmful investments to deliver high returns, reduce risk exposure, and enhance resilience.

"If you follow the money, you see the size of the challenge ahead of us. We can either invest into nature's destruction or power its recovery—there is no middle ground," said Inger Andersen, Executive Director of UNEP. "While financing nature-based solutions crawls forward, harmful investments and subsidies are surging ahead. This report offers leaders a clear roadmap to reverse this trend and work with nature, rather than against it."

Researchers have moved a step closer to new treatments for a rare and often devastating autoimmune disease that interferes with how the brain communicates.

The study highlights a vulnerable point in the disease process, one that could eventually be used to design more precise therapies. The condition develops when the immune system mistakenly targets the NMDA receptor, a protein essential for learning, memory, and normal brain signaling. By identifying where this attack occurs, the work also opens the possibility of a future blood test that could flag the disease earlier, when current treatments may be more effective.

The disorder gained public attention through the bestselling memoir and the 2016 film “Brain on Fire,” but it remains uncommon. Each year, it affects an estimated 1 in a million people, most frequently young adults in their 20s and 30s. Despite its rarity, the illness can progress rapidly and cause life-threatening neurological symptoms.

In people with the condition, the immune system produces anti-NMDA receptor autoantibodies that attach to NMDA receptors in the brain and disrupt their function. This immune-driven damage can lead to dramatic changes in behavior and cognition, severe memory loss, seizures, and, in some cases, death.

Pinpointing a Molecular Targetz
In the new study, scientists focused on identifying exactly where these harmful antibodies bind. They discovered specific regions on a subunit of the NMDA receptor that appear to be central to the disease process. Blocking these regions, the researchers suggest, could help stop or even reverse the progression of symptoms.