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.