Over the course of billions of years, the universe has steadily been evolving. Thanks to the expansion of the universe, we are able to “see” back in time to watch that evolution, almost from the beginning. But every once in a while we see something that doesn’t fit into our current understanding of how the universe should operate. That’s the case for a galaxy described in a new paper by PhD student Sijia Cai of Tsinghua University’s Department of Astronomy and their colleagues. They found a galaxy formed around 11 billion years ago that appears to be “metal-free”, indicating that it might contain a set of elusive first generation (Pop III) stars.
Space News & Blog Articles
The Cygnus X star-forming region is about 4,600 light-years away. It contains a huge number of massive protostars, and one of the most massive star-forming molecular clouds known. With all of this activity, it's not surprising that it also hosts some objects that have puzzled astronomers.
Without water, life is highly unlikely, as far as scientists understand it. The entire idea of a habitable zone around other stars is based on a planet's potential to have liquid water on its surface. But where does this water come from?
Interstellar objects are really rather rare. Since astronomers first spotted 'Oumuamua racing through our Solar System in 2017, we've detected only two more visitors from beyond; comet Borisov in 2019, and now 3I/ATLAS, discovered on 1 July 2025. These objects offer tantalising glimpses into other stellar systems, carrying material formed around distant stars. But they don't linger. They sweep through on hyperbolic trajectories, never to return, which makes every observation precious.
I have to confess, despite spending years gazing at the night sky, telescope at the ready, tracking planets and hunting for deep sky objects, I only actually saw the Man in the Moon about five years ago. There I was, exploring lunar maria and highland regions, and I'd somehow never noticed what humans have been seeing for millennia.
Let’s start out with something that we can say for certain: we live in an expanding universe. Every single day, the universe gets a little bit bigger than it was the day before. But right away, when we say something like “we live in an expanding universe” certain questions start to pop up, and they’re far and away the most common kinds of questions that I get asked. If the universe is expanding, then what is it expanding into? And what is it expanding from? Where’s the edge of the universe, and where is it’s center?
Satellite megaconstellations are quickly becoming the backbone of a number of industries. Cellular communication, GPS, weather monitoring and more are now, at least in part, reliant on the networks of thousands of satellites cruising by in low Earth orbit. But, as these constellations grow into the tens of thousands of individual members, the strain they are putting on the communications and controls systems of their ground stations is becoming untenable. A new paper from Yuhe Mao of the Nanjing University of Aeronautics and Astronautics and their co-authors hopes to alleviate some of that pressure by offloading much of the control scheme and network decision-making logic to satellites themselves.
I honestly don’t have a decent analogy for you to explain how the universe is expanding without a center and without an edge. It just does, whether we can wrap our minds around it or not. But I CAN give you a way to think about it.
An expanding universe complicates this picture just a little bit, because the universe absolutely refuses to be straightforward. Objects are still emitting light, and that light takes time to travel from them over to here, but in that intervening time the universe grows larger, with the average distance between galaxies getting bigger (yes, I know that sometimes galaxies can collide, but we’re talking on average, at big scales here).
It is a scientific consensus that water once flowed on Mars, that it had a denser atmosphere, meaning that it was once habitable. Unfortunately, roughly 4.2 to 3.7 billion years ago, Mars' rivers, lake, and global ocean began to disappear as solar wind slowly stripped its atmosphere away. For scientists, the question of how long it remained habitable has been the subject of ongoing inquiry. Whereas some scientists maintain that Mars ceased being habitable billions of years ago, recent research suggests that it experienced periods of habitability that lasted for eons.
The Milky Way contains more than 100 billion stars, each following its own evolutionary path through birth, life, and sometimes violent death. For decades, astrophysicists have dreamed of creating a complete simulation of our Galaxy, a digital twin that could test theories about how galaxies form and evolve. That dream has always crashed against an impossible computational wall.
Material science plays a critical role in space exploration. So many of the challenges facing both crewed and non-crewed missions come down to factors like weight, thermal and radiation tolerance, and overall material stability. The results of a new study from Young-Kyeong Kim of the Korea Institute of Science and Technology and their colleagues should therefore be exciting for those material scientists who focus on radiation protection. After decades of trying, the authors were able to create a fully complete “sheet” of Boron Nitride Nanotubes (BNNTs).
The surface of the Earth is finite. We can measure it. If it was expanding, then its size would grow with time. And once again, good ol’ Earth helps us understand what the universe might be doing beyond our observable horizon.
According to the leading theory of how the Earth-Moon system formed (the Giant Impact Hypothesis), a Mars-sized object (named Theia) collided with a proto-Earth 4.5 billion years ago. This turned both objects into molten lava, which eventually coalesced and cooled to form the Earth and Moon. Over time, the Moon migrated outward, eventually reaching its current, tidally locked orbit around Earth, where one side is permanently facing us. For decades, scientists have debated where Theia may have originated, whether it formed in the inner or outer Solar System.
Blue Origin just achieved another impressive milestone with its new heavy-launch vehicle, the partially reusable New Glenn rocket. On Thursday, Nov. 13th, during what was only the second launch of the New Glenn (NG-2), Blue Origin launched a NASA payload destined for Mars. This was the ESCAPADE (Escape and Plasma Acceleration Dynamics Explorers) mission, a pair of twin satellites that will study how solar wind interacts with Mars’ magnetic environment and how this interaction drives atmospheric escape.
In early October, the third interstellar object (ISO) to visit our Solar System (3I/ATLAS) made its closest flyby to Mars, coming within 30 million km (18.6 million mi) of the Red Planet. This placed it within view of several missions currently operating there, which are operated by three space agencies: NASA, the European Space Agency (ESA), and the China National Space Agency (CNSA). While the ESA released images taken by the Mars Express* and *ExoMars Trace Gas Orbiter (TGO), and China released images taken by the Tianwen-1 orbiter, NASA was unable to release any data due to the government shutdown.
Using in-situ propellant has been a central pillar of the plan to explore much of the solar system. The logic is simple - the less mass (especially in the form of propellant) we have to take out of Earth’s gravity well, the less expensive, and therefore more plausible, the missions requiring that propellant will be. However, a new paper from Donald Rapp, the a former Division Chief Technologist at NASA’s JPL and a Co-Investigator of the successful MOXIE project on Mars, argues that, despite the allure of creating our own fuel on the Moon, it might not be worth it to develop the systems to do so. Mars, on the other hand, is a different story.
Human beings are pretty familiar with the concept of "ice ages." Not only is their ample physical evidence to suggest that glacial periods occurred during the Pleistocene epoch - which lasted from ca. 2.58 million to 11,700 years ago, there are even Indigenous oral traditions that speak of lake formation and dramatic climate shifts in the distant past. Far from being mere myths, these traditions are considered preserved accounts that are corroborated by scientific findings. However, the cycles of glacial and interglacial periods that characterize the Pleistocene were merely the latest in a long line of historical shifts in Earth's climate.
Let’s rewind the clock back…oh, I don’t know, let’s say a hundred years. It was 1917, and Einstein had just developed his general theory of relativity. It was a masterpiece, giving us our modern day view of the gravitational force. And like anybody curious about gravity, Einstein decided to apply his new equations to the evolution of the universe.
All motion is relative. That simple fact makes tracking the motion of distant objects outside our galaxy particularly challenging. For example, there has been a debate among astronomers for decades about the path that one of our nearest neighbors, the Large Magellanic Cloud (LMC), took over the last few billion years. A new paper from Scott Lucchini and Jiwon Jesse Han from the Harvard Center for Astrophysics grapples with that question by using a unique technique - the paths of hypervelocity stars.
To be fair, all scientific models are in some sense wrong. They’re all approximations of reality. They’re all mathematical models that we use to describe and understand our observations and measurements. And like I said, the LCDM model has, over the course of almost a quarter century, proven to be enormously resilient, flexible, and powerful when describing broad swaths of nature.

