What if our understanding of Uranus and Neptune’s compositions have been wrong, specifically regarding their classifications as “ice giants”? This is what a recent study accepted for publication in *Astronomy & Astrophysics* hopes to address as a team of researchers from the University of Zurich investigated the interior structures of Uranus and Neptune. This study has the potential to help scientists not only better understand the formation and evolution of Uranus and Neptune but could also provide key insights into Jupiter and Saturn, and gaseous exoplanets, too.
Space News & Blog Articles
Today, it's a scientific consensus that Mars was once a very different place, with a warmer, denser atmosphere and liquid water on its surface. This is evidenced by flow channels, delta fans, lakebeds, and many other features that form in the presence of flowing water here on Earth. Based on the way many of these channels feed into the Northern Lowlands on Mars, scientists speculate that this region was once home to an ocean that covered the northern hemisphere. According to new research from the University of Arkansas, there is a strong case for the existence of this ancient ocean.
The Big Bang essentially created two elements: hydrogen and helium. It also produced tiny traces of lithium and a few other light isotopes, but in the beginning there was hydrogen and helium. All the other, heavier elements formed later, either in the cores of stars, through stellar collisions, or other astrophysical processes. Even now hydrogen and helium make up so much of the material world that astronomers refer to all other elements as metals. Dust in the wind, you might say.
Duplicating expensive resources is expensive and wasteful, and most people would agree it's unnecessary. However, the planned increase in major satellite constellations is currently causing a massive duplication of resources as individual companies and even countries try to set up their own infrastructure in space. What’s more, there is a relatively limited amount of space in Low Earth Orbit (LEO), where many of these satellites are supposed to go - any more than that and a single collision could cause Kessler Syndrome, where many of the ones already in orbit would be destroyed and we wouldn’t be able to launch any more for a long time. A new paper from researchers at the National University of Defense Technology in China suggests an alternative to these multiple megaconstellations - a single, modular system similar to how cloud computing works on the current internet.
The China National Space Administration's (CNSA) Tianwen-2 probe is currently at a distance of about 43 million km (26.7 million mi) from Earth. This places it in a stable geosynchronous orbit (GSO) and almost halfway between its first destination, the Near Earth Asteroid (NEA) 469219 Kamo'oalewa, which is still 45 million km (~28 million mi) away. As is customary for interplanetary missions, its controllers are using the flight phase to test the spacecraft's instruments and make sure they are in working order.
Peering back into the early years of the universe requires scientists to make a lot of assumptions. But sometimes, we get better instruments that then allow them to either confirm or replace those assumptions. That happened recently when it came to our study of J0529, a supermassive black hole that is currently the brightest known quasar in the universe. A new paper from a massive team of researchers used the GRAVITY+ instrument on the European Southern Observatory’s (ESO’s) Very Large Telescope (VLT) Interferometer to map this unique object’s Broad Line Region (BLR), and thereby calculated a new, updated mass that is 10 times smaller than previous estimates.
Periodically, the European Space Agency (ESA) releases images that provide breathtaking views of the cosmos, courtesy of its premier missions. This includes a relative newcomer to party with the ESA/Webb Picture of the Month, which showcases the high-resolution and ultra-sensitive capabilities of the James Webb Space Telescope (JWST). This month's feature: eight stunning images of gravitationally-lensed galaxies observed by Webb during its Cycle 1 General Observation (GO) surveys. The study of these lensed galaxies are providing insight into the early Universe and how galaxies have evolved with time.
Interstellar visitor 3I/ATLAS has been constantly changing as it makes its way through our solar system. That’s to be expected, as, for the first time in potentially billions of years, it's getting close to the energy put out by a star. Scientists have been keeping a close watch on those changes, both to ensure there’s nothing unexplainable by our current understanding, but also to compare 3I/ATLAS to both previous interstellar visitors as well as comets in our own solar system. A recent paper from European researchers describes how the changes in a particular material ratio in 3I/ATLAS’ coma fit with our current understanding of cometary geology.
Making a black hole is easy. Just squeeze a bunch of stuff into a small enough volume. It doesn't even matter what you use. You can collapse stars, planets, old car tires, Labubus, or missing left socks. The resulting black hole will only depend on the mass, rotation, and electric charge of the original material.
The Copernican Principle, named in honor of Nicolaus Copernicus (who proposed the heliocentric model of the Universe), states that Earth and humans do not occupy a special or privileged place in the Universe. In cosmological terms, this essentially means that Earth is representative of the norm, and life is likely to exist throughout the cosmos. While our efforts to find extraterrestrial life, a field of study known as astrobiology, have yielded no results so far, these efforts have been limited in scope. As a result, scientists are forced to speculate based on the only planet known to support life—i.e., Earth.
Rogue planets, also known as free-floating planets (FFP) or isolated planetary-mass objects (iPMO), have become a major focus for astronomers. The first such objects were detected in 2000 by teams at the United Kingdom Infrared Telescope (UKIRT) and the Keck Observatory, though earlier detections were made that were unconfirmed at the time. Since then, research has shown that these planets may actually be more common than planets that orbit stars, with some estimates placing the population as high as 4 trillion in our galaxy alone.
In principle, discovering new exoplanets is pretty easy. Simply measure the brightness of a star over time, and when a planet passes in front of the star, the brightness will dim slightly. The more the brightness dips, the larger the planet in relation to the star. This transit method is so effective it is how we have found the majority of exoplanets. But astronomers want to do much more than simply discover planets, and for that you need to dive into the details.
For more than twenty years, the Mars Express orbiter has studied the Red Planet and remains the European Space Agency's (ESA) only operational mission. In that time, it has provided the most complete map of the Martian atmosphere and its chemical composition. It has also studied Mars' innermost moon (Phobos) in stunning detail, and traced the flow channels, delta fans, and chaos terrain that demonstrate that liquid water once flowed on the planet's surface. In addition, the images taken by the orbiter have been used to create detailed mosaics that have breathtaking 3D views of the landscape.
One of the greatest accomplishments of the James Webb Space Telescope is the way it has allowed scientists to examine galaxies that existed when the Universe was very young. This is one of the major objectives that informed Webb's design, which was to provide high-resolution images of the earliest galaxies, allowing astronomers and cosmologists to gain a better understanding of how they have evolved over time. Intrinsic to this is the study of early massive black holes that have since evolved into the supermassive black holes (SMBHs) that reside at the centers of galaxies today.
Modeling something like geysers on a far-away moon seems like it should be easy. How much complexity could there possibly be when a geyser is simply a hole in some ice shooting superheated water through it? The answer is pretty complex, to be honest - enough that accurate models require a supercomputer to run on. Luckily, the supercomputing cluster at the University of Texas, known as the Texas Advanced Computing Center, gave some time to researcher modeling Enceladus’ ice plumes, and their recent paper in JGR Planets discusses the results, which show there might not be as much water and ice getting blown into orbit as originally thought.
Interest in icy moons has been growing steadily as they become more and more interesting to astrobiologists. Some take the majority of the attention, like Enceladus with its spectacular geysers. But there are interesting ones that might be hiding amongst even thicker ice shells in the Uranian system. A new paper published in Icarus from researchers at the Planetary Science Institute, Johns Hopkins University, and the University of North Dakota, looks at what Ariel, the fourth biggest moon in the Uranian system, might look like under its icy surface.
Enceladus’ ice continues to get more and more intriguing as researchers continue to unlock more secrets taken from a probe over ten years ago. When Cassini crashed into Saturn in 2017, it ended a 13 year sojourn that is still producing new research papers today. A recent one in Nature Astronomy from the researchers at the Freie Universität Berlin and the University of Stuttgart found hints of organic molecules discovered for the first time on the icy moon, some of which could serve as precursors to even more advanced biomolecules.
There are plenty of exoplanets scattered throughout the galaxy, so it would stand to reason there are also plenty of stars that are in the process of forming new exoplanets. Tracking down stars that are in different stages of that process can shed light on the exoplanet formation process, and potentially even on how planets in our own solar system developed. But determining what star systems are going through that process, let alone where they are in the process itself, can be tricky. A new paper in Nature Astronomy from Tomohiro Yoshida and his co-authors at the National Astronomical Observatory of Japan and several other Japanese and American research institutions, seems to have found one that finally answers a mystery that has stood in planetary formation theory for decades - how do gas giant exoplanets form so far away from their stars?
One dedicated amateur shows what can be done with remote telescope access, knowledge and a little patience.

