Neptune is definitely the odd one out of the gas giants. It’s tilted at a strange angle, and its moons are completely different from any other gas giant we know of. A new paper, published in Science Advances from researchers at CalTech, posits that might be because Triton, by far Neptune’s largest moon, absolutely obliterated the regular moon system it previously had, except for one particular exception - Nereid.

Unfortunately there’s more bad news to report on the clear skies front. A new paper, available in pre-print on arXiv from researchers at NASA’s Ames Research Center, reports that 73.3% of images the agency’s new SPHEREx space telescope collected between May and September of last year were contaminated by at least one artificial satellite trail. And it’s only going to get worse from here.

The ekpyrotic theory tries to beat inflation with bouncing higher-dimensional branes, no singularity, and a universe that has always existed. A tour of the prettiest version of the idea and how it claims to handle flatness, dark energy, and the entropy that doomed earlier cyclic models.

We witnessed a surprise outburst late last week, from a lesser known periodic comet. Posts flashed across message boards late last week, alerting comet watchers to a dramatic change in brightness for periodic comet 220P McNaught. Though it wasn’t on our list for bright comets to watch for in 2026, Comet 220P is now in range of binoculars or a small telescope, low to the east at dawn as it heads towards perihelion this coming weekend.

If we’re to reach another star, chemical propulsion will not get us there in any reasonable time frame. We’re going to need a different propulsion technology, and one of the most promising seems to be a solar sail. These giant reflective surfaces form the basis of many interstellar missions. Combined with giant lasers pushing them, they can be accelerated to speeds unreachable by any other current technologies. However, according to a new paper available on arXiv from Chao Shen and Jiaze Li of the Harbin Institute of Technology, once those missions start reaching a significant percentage of the speed of light they’re going to run into a drag force from the light itself.

An international team led by astronomers at the University of Sydney has uncovered the clearest evidence yet for the origin of an unusual class of cosmic signals. In doing so, they have identified a rare stellar system that is providing scientists with a natural laboratory to study extreme physics.

Inflation is awkward, possibly not even a proper theory, and it has reigned over cosmology for forty years anyway. Here is what it claims, the flatness, horizon, and monopole problems it solves, the structure-formation prediction it nailed, and the deep problems it still cannot escape.

Scientists at the SETI Institute searched for technological signals from 3I/ATLAS, the third interstellar object observed in our Solar System. Using the Allen Telescope Array (ATA) at the Hat Creek Radio Observatory in Northern California, the team scanned a wide range of radio frequencies for signs of extraterrestrial technology and found none, as expected based on other astronomical observations showing that the object exhibits natural comet-like composition and behavior. “Eventually, our own Voyager spacecraft will be extraterrestrial artifacts in other stellar systems,” said Dr. Sofia Sheikh, lead author on the paper. “Given that, it is important that we understand the natural distribution of interstellar objects so that we will be able to identify any anomalies that could one day be signs of an artificial interstellar object.” The team observed 3I/ATLAS for more than seven hours with the ATA, covering 1 to 9 gigahertz. This broad range allows scientists to search for narrowband radio signals, which are not produced by in nature and would be evidence of technology.

A look at why a cyclic, eternally repeating universe is such an appealing idea, and why the first serious attempt to build one, Richard Tolman's 1930s model of endless big bangs and big crunches, collapsed under the weight of entropy. The Big Bang keeps demanding a beginning.

Rocket scientists have always faced a trade-off in propulsion technologies. Chemical rockets can provide lots of oomph, but burn through fuel so quickly they can only do so for a few minutes. Electric propulsion, on the other hand, can run for days, but the pushing power they provide is miniscule compared to their chemical cousins. A new paper in the Journal of Propulsion and Power from researchers at MIT describes a system that might be the best of both worlds - a propulsion system that includes an electrospray thruster that uses a chemical rocket propellant, and can seamlessly switch to a chemical rocket when needed.

An international committee of experts says it has updated its rules for evaluating and revealing the detection of extraterrestrial intelligence. The revisions to the decades-old Declaration of Principles, created and maintained by the International Academy of Astronautics' SETI Committee, come just days before the release of "Disclosure Day," a movie about alien visitation directed by Steven Spielberg.

The first mission devoted to observing the Martian atmosphere and its evolution, NASA’s MAVEN (Mars Atmosphere and Volatile Evolution), has ended after more than 11 years in orbit at Mars and a decade beyond its primary, one-year mission.

Ever since the first protoplanetary disk was discovered in 1984 around the star Beta Pictoris, these objects have presented astronomers with laboratories to study the births and evolution of worlds around distant stars. A team at France's National Center for Scientific Research (CNRS) and the University of Bordeaux, made a breakthrough in understanding these planetary birthplaces when they directly observed the rotation of a protoplanetary disk around the young star AB Aurigae.

Using data from NASA’s James Webb Space Telescope, astronomers led by researchers at the University of California, Riverside have produced the most detailed map of the cosmic web ever made, tracing the network of galaxies all the way back to when the universe was one billion years old.

According to theory, all active black holes should produce winds or jets. Astronomers have long searched for wind around the Milky Way’s central supermassive black hole. New images reveal a vacant, cone-shaped region pointing to the black hole. According to new research, only a supermassive black hole could've created this region.

Stephen Hawking predicted that stars can capture primordial black holes (PBH). The PBH find their way to the stellar core, creating a Hawking star. There are two possible outcomes, both deadly for the star. Either it explodes rapidly, or it's slowly consumed by the parasitic PBH.

Astronomers have developed a technique that allows them to detect cloud cycles on distant exoplanets. Using data from the James Webb Sapce Telescope (JWST), the astronomers found that mornings and evenings on the gas giant WASP-94A b have extremely different weather patterns: mornings are riddled with sand clouds, while the skies are clear in the early evenings. By isolating the clouds, researchers can more accurately measure a planet’s atmosphere and provide a clearer picture of the planet’s composition. WASP-94A b, for example, has much less oxygen and carbon than astronomers perviously calculated, making its atmosphere much more like Jupiter than they had originally thought.

New research shows how unmagnetized worlds like Mars can still deflect some of the Sun's solar wind. Unlike magnetospheres that form around planet's like Earth, this effect takes place in Mars' ionosphere. It's called the Zwan-Wolf effect, and it's not clear how deep into the atmosphere it operates.

Scientists using the Euclid space telescope found a red-dwarf brightness “gap” in the population of a globular cluster—an ancient, crowded collection of stars. A similar gap was detected by the Gaia observatory in nearby stellar populations, but it has never before been seen in a globular cluster.

It’s a familiar annual question, that we’re already hearing as we enter into June. “What are those two bright objects in the west?” They’re none other than the two brightest planets in the sky, Jupiter and Venus. Keep an eye on the dusk sky over the next week, and you’ll see the two worlds getting ever closer to each other in the west. Though this happens every year or so, an evening conjunction assures that lots of the general public will see one of the best planetary pairings of 2026.

In our final installment in the series, we'll examine all the close calls, possible candidates, and instances in which extraterrestrial signals could not be ruled out

A multi-year survey of millions of stars in the Small Magellanic Cloud shows that the dwarf galaxy is expanding rather than rotating. This is due to the influence of its larger neighbour, the Large Magellanic Cloud.

The early Universe is full of massive galaxies that stopped forming stars very early. They're called massive quenchers (MQ) and they're challenging to explain. New research shows that another type of galaxy, dusty star-forming galaxies (DSFGs) can explain why. It's all about mergers, starbursts, and AGN feedback.

Astronomers studying wind speeds on distant exoplanets have discovered weather systems driven by magnetic fields, rather than the largely hydrodynamic weather patterns observed on Earth. This discovery is among the best evidence yet for the existence of magnetic fields on exoplanets.

The strength of gravity is different on every body in the solar system. Whether it's the crushing weight of Jupiter or the miniscule pull of a small asteroid, this fundamental force of physics still has a major impact on the material those bodies are made up of. A new paper from researchers at the University of Duisburg-Essen and the German Aerospace Center (DLR) showcases just how different it can be by letting planetary simulants freefall inside a giant drop tower and measuring how “fluffy” the space dirt got.

Jeff Bezos' Blue Origin is assessing damage to its launch pad after a rocket exploded during a test firing, creating a giant orange fireball seen and felt for miles around.

Galactic collisions are events of breathtaking proportions. The Supermassive Black Holes (SMBHs) at their centers plunge into a chaotic orbital dance that eventually coalesce into a single remnant. On their way to that point, they could eventually get “kicked” out of the center of their galaxy - and finding these “recoiling” black holes has been a challenge of cosmology for decades. A new paper, available on arXiv by an international team, used a novel idea to track down these fast-moving behemoths.

The prototype ngVLA antenna tested its systems by observing and tracking the Crab Nebula, also known as Taurus A (3C144), the remnant of an exploded star.

It might not seem like it, but the Moon is constantly being both sandblasted and baked. Its lack of a thick atmosphere allows micrometeorites to impact the surface at speed, and the solar wind isn’t held back either, baking the regolith with a constant flow of high-energy particles. These processes drive what is called “space weathering”, and it can drastically alter the physical and chemical properties of the lunar dirt over the course of billions of years. And we’re finally getting a better sense of what that means in practice thanks to two new papers from researchers at the Chinese Academy of Sciences and Peking University, which used advanced electron tomography and spectroscopic techniques to analyze samples returned from the Chang’e-5 mission to the near side of the Moon.

Though it's a toxic chemical, hydrogen cyanide (HCN) is also important for the development of life. It's a precursor to things like amino acids and nucleic acids and plays a central role in theories of the origin of life on Earth. Recently, difficult questions have been asked about how it could have formed on the early Earth. But the authors of new research in PNAS seemed to have figured it out.

The search for any sign of life on Mars continues. In the latest update, a new data release from Curiosity’s Chemistry and Mineralogy (CheMin) - essentially the rover’s portable X-ray diffraction lab - and published in a paper in Science, analyzes 20 different rock samples from various elevations of Mount Sharp, the mountain in the center of Gale Crater that Curiosity has been slowly climbing. In the paper, the researchers describe how the size of the crystals in those samples could help scientists determine where to look for evidence that life might have evolved on the Red Planet.

3I/ATLAS has caused quite a stir over the last year, inviting astronomers to update what they know about other solar systems as well as our own. However, this third interstellar visitor may have an unexpected impact on our understanding of dark matter. A new paper, available in pre-print on arXiv from researchers at the University of Hamburg, attempts to calculate the impact that the presence of large amounts of interstellar objects (ISOs) would have on our calculation of dark matter in our galaxy.

The dwarf planet Ceres has a surface that seems to get more perplexing with each new study. A recent paper presented at EGU26 in Vienna only adds to its mystery.

The JWST found an abundance of overmassive black holes at high redshifts, pushing the limits of black hole (BH) science in the early Universe. Results have claimed that these BHs are significantly more massive than expected from the BH mass-host galaxy stellar mass relation derived from the local Universe. But new research shows they were just outliers in the normal range of masses that don't require any special causes.

Multi-billion dollar space telescope programs aren’t only feats of aerospace engineering. They also feature “lies, damn lies, and statistics”. Or at least statistics. They definitely feature those, as does all good observational astronomy. The problem with statistics is, in order to get a clear definitive answer, you need lots of samples. And, to put it mildly, it’s hard to find lots of samples of planets with alien life on them. And even harder to prove that the signals we think are caused by alien life aren’t caused by some other non-biological process. Or at least that’s the theory underpinning a new paper available in pre-print on arXiv from David Kipping of Columbia University (and Cool Worlds YouTube fame).

The universe is full of fascinating structures, and some of the most striking take shape inside the giant clouds where stars are born. There, streams of gas appear to converge from all directions toward a dense central hub, like spokes meeting at the center of a wheel. New simulations show why this is, and why star formation overall is so inefficient.

The physics of neutron stars are almost too fantastic to believe. Something the weight of two Suns compacted to a sphere the size of a city. Each teaspoon of its material would weigh billions of tons. If you’ve done any reading on the topic, you’ve heard these facts before. But despite the intense interest these extreme objects hold, we are still actively learning lots about them. One of the most pertinent outstanding questions is where is the line between becoming a neutron star and becoming a black hole when a star dies. A new paper by researchers at the HUN-REN Wigner Research Centre for Physics in Hungary describes what they believe to be a definitive answer to that question - between 2.2 and 2.3 solar masses.

Jupiter helped create the different rocky bodies in the Solar System. The massive gas giant created a planet-induced pressure bump in the gas in the disk surrounding the young Sun. This pressure bump filtered different types of dust at different times, leading to the formation of planetesimals with different compositions at different times.

4.5 billion years ago was an interesting time for the Earth. The atmosphere was thick and what we would now think of as toxic. The Moon, which was freshly formed, looks much more massive than it does today and faintly glows with the residual heat from its own creation. And the floor was literally lava. Everywhere. If there were any children alive at the time, they would have no chance of winning that game. But for a long time, scientists had thought this molten phase of the Earth didn’t last long. But according to a new paper, available in preprint on arXiv by researchers at the Kapteyn Astronomical Institute, it might have lasted for upwards of half a billion years.

The TRAPPIST-1 system, located about 41 light years from Earth, has been a focal point of much exoplanetary discussion - mainly because it has 7 confirmed planets orbiting a dim M-dwarf star. Two of those planets - TRAPPIST-1e and -1f - are thought to be in the star’s habitable zone. However, the habitable zone of M-dwarfs is so close to the star itself the planets are likely tidally locked to it, meaning they have a permanent day and night side, with a “twilight terminator” in between. Armed with that knowledge, scientists have been attempting to model the climate on these two exoplanets, and a new paper from Jacob Haqq-Misra of Blue Marble Space uses a new type of climate model to accurately do so with much less computational power.

It’s 2234, you’re on your annual class field trip touring exoplanets, and your teacher informs everyone they can pick one more exoplanetary system to explore before heading back to Earth. You and your classmates are exhausted from the day’s activities and you’re hungry. However, you get really excited because you already know what everyone will want. You and your classmates all shout in unison, “The young and far away puffy ones!”

It’s June 2027, and you’re fresh off defending your PhD studying the direct imaging of exoplanets while starting your postdoctoral journey at NASA Jet Propulsion Laboratory. The trauma of eating ramen and living off a sub-living wage for the last five years of your life is still fresh in your brain. But you’re excited to finally get your real career started with funding you received for viewing time on the much-anticipated Nancy Grace Roman Space Telescope (Roman for short). You begin to download the first set of data as your eyes tear up knowing your entire journey in research and academia is about to be worth it.

It’s 2165, and methane is in high demand, especially after the Titan Treaty of 2145 made it illegal to harvest methane from Saturn’s moon, Titan. But the advent of interstellar travel has made exoplanetary exploration far easier, enabling corporations to identify and harvest methane from exoplanets. However, it’s far cheaper and easier to harvest methane from exoplanets with reasonable (also called temperate) temperatures, because it means higher quantities of methane. The Exoplanet Exploration Corporation decides to send its first ship to one such exoplanet loaded with methane that could bring their quarterly financial statements back into the green.

Before any spacecraft can survive the Moon, it has to survive something almost as brutal, a giant metal chamber in Houston that strips away every molecule of air and swings temperatures from scorching to freezing in minutes. Blue Origin's lunar lander just spent time in exactly that chamber and it came out the other side ready for the real thing.

We are closer than ever to detecting signs of life on another world. The James Webb Space Telescope is already ‘sniffing’ alien atmospheres, and the Habitable Worlds Observatory is being built specifically to find biology beyond Earth. But a new paper raises an uncomfortable question; when we do find that first biosignature, will it actually tell us anything meaningful about life in the universe? The answer, it turns out, might be no.

In recent decades, the Search for Extraterrestrial Intelligence (SETI) has seen a revival, and future surveys will benefit from new technologies. Similarly, our perception of what technologies an advanced civilization might use has expanded.

Every galaxy we know of spins. It's one of those rules of the universe so fundamental that astronomers barely think about it anymore. So when the James Webb Space Telescope pointed at one of the most massive galaxies in the early universe and found…well nothing. No spin, just stillness. They had to look twice.

For nearly thirty years, dark energy has been cosmology's great get out of jail free card, the invisible, mysterious force we invented to explain why the universe is expanding faster than it should be. Now a team of mathematicians says we may never have needed it at all. And the implications are stranger than you might think.

An early galaxy cluster named after an Indian lake is teaching astronomers about influences on galaxy evolution in the infant Universe. Astronomer Ronaldo Laishram of the National Astronomical Observatory of Japan (NAOJ) used the Subaru Telescope’s wide-field camera, Hyper Suprime-Cam (HSC), to conduct a large sky survey to look for early galaxies with active star formation. The result was the discovery of a massive protocluster of galaxies that existed some 12.6 billion years ago, very early in cosmic time. Detailed study of this region could give new insight into how galaxies and their clusters form and evolve.

A team of scientists is exploring ways to use dark craters at the lunar poles as sites for ultrastable lasers to aid in surface and near-lunar navigation. The group, led by Physicist Jun Ye, an expert on lasers and precision measurements, were discussing the types of instruments that Artemis astronauts could install and use during their time on the Moon.