Notices by Fraser Cain (fraser@m.universetoday.com)

Solar sails get their propulsion from the Sun, so they don't need to carry propellant, but they come with their own challenges. A sail has a large surface area but a low mass, which creates a huge moment of inertia and makes it difficult to control, especially with reaction wheels. A team of engineers has developed a reflectivity control device, where thin membranes on the sail change their reflectivity, producing less force and allowing the sail to change direction.

https://arxiv.org/abs/2505.19865

New data from JWST reveal icy dust in a galaxy far away, seen at a time when it was 5 billion years younger than it is now. This dust is surprisingly similar to dust we see in the Milky Way, which gives a tantalizing hint about what star and planetary formation could have been like much earlier in the Universe. When you consider that the Solar System started forming about 4.5 billion years ago, it indicates that similar planetary systems could be forming there too.

https://now.tufts.edu/2025/06/06/peeking-through-space-dust-see-how-ancient-universe-formed

Satellites in low-Earth orbit are still passing through a tiny amount of the Earth's atmosphere, which increases their drag, eventually pulling them into a fiery re-entry. But serious solar storms can cause the Earth's atmosphere to puff out, causing more drag on satellites and increasing their rate of orbital decay. A new paper discovered that a powerful solar storm in 2018 caused 25 m of orbital decay on a satellite. They propose how to decrease susceptibility to drag.

https://arxiv.org/abs/2506.03305

NASA's 2001 Mars Odyssey orbiter captured this incredible image of the giant shield volcano Arsia Mons, poking through the cloud tops at Martian dawn. Arsia and the other megavolcanoes on Mars are so tall they're often surrounded by water ice clouds in the early morning. Odyssey is normally staring straight down, so to capture this unique angle, it had to rotate 90 degrees while in orbit so that it could capture a side perspective view of the volcano.

https://www.jpl.nasa.gov/news/nasa-mars-orbiter-captures-volcano-peeking-above-morning-cloud-tops/

The Large Hadron Collider has changed particle physics, and now scientists are dreaming up even bigger supercolliders. But humanity can't match the raw particle-colliding power of a supermassive black hole. In a new paper, researchers describe how supermassive black holes create a dense environment where particles are spinning at relativistic speeds and crashing into each other, releasing other particles that could be detectable on Earth.

https://www.eurekalert.org/news-releases/1085703

A Chinese rocket startup called Space Epoch just tested a reusable booster rocket called Yanxingzhe-1, soft landing in the ocean off the coast of Shandong Province in eastern China. The 26.8-meter rocket is made of stainless steel and has a diameter of 4.2 meters (Falcon 9 is about 41 meters with a 3.7-meter diameter). The prototype blasted off, completed a 125-second flight, reached an altitude of 2.5 km, and then descended, reignited, and soft landed in the ocean.

https://news.cgtn.com/news/2025-05-29/Chinese-commercial-rocket-completes-vertical-sea-recovery-test-1DMefpHW0qQ/p.html

Astronomers have discovered a bizarre new pulsar-like object that's throwing out regular bursts of radio waves every 44 minutes. Totally normal, long-period pulsar behavior. But observations from Chandra show that it's also releasing a blast of X-rays every 44 minutes as well. The astronomers also found that the amount of both radio waves and X-rays has been decreasing over the course of six months. Is this a totally new type of object?

https://chandra.harvard.edu/press/25_releases/press_052825.html/

Astronomers have discovered a total of 20 asteroids that share an orbit with Venus. Almost all of these asteroids are highly eccentric, discovered when they were at their closest to Earth, which suggests there are many more that haven't been found. These asteroids are often lost in the glare of the Sun and could be a source of significant collision hazards with Earth, releasing the energy of hundreds of megatons of TNT if they struck our planet.

https://arxiv.org/abs/2505.15968

When spacecraft are constructed, they're assembled in special cleanrooms that are engineered to have extremely low levels of dust and microbes. Now, researchers have found that specific types of extremophiles have evolved to thrive in environments designed to remove all their competitors. They examined space agency cleanrooms and found 26 novel bacterial species, with specific features that let them handle decontamination and radiation.

https://www.eurekalert.org/news-releases/1083406

The Cosmic Microwave Background Radiation is one of the most important tools in astronomy, confirming the Big Bang and many other fundamental aspects of the early Universe. According to a new paper, however, we might not be seeing a clear view of the CMB. Instead, the first galaxies in the Universe might have emitted radiation that contributes to the CMB and could explain 1.4% of its light—maybe even more. This could have consequences for the standard model of cosmology.

https://www.uni-bonn.de/en/news/087-2025

Returning to Earth is a free ride, using the friction of the atmosphere to shed enormous velocity. But re-entering spacecraft build up high temperatures on their exteriors, which can destroy them (remember the Columbia disaster)? A team of engineers is investigating how a trick of nature—sweating—could work during spacecraft re-entry. A spacecraft would create a layer of gas on its surface that would cool the spacecraft and prevent direct contact with the hot gases.

https://www.eurekalert.org/news-releases/1082474

A mystery in astronomy is how supermassive black holes grew so big, so quickly. Astronomers have looked for quasars, actively feeding supermassive black holes, as a way to measure how much new material they’re accumulating, contributing to their growth. They studied nebulae near the quasars that light up when the quasar is releasing radiation and found that many of the farthest quasars have only been active for a few hundred thousand years, not long enough to grow.

https://arxiv.org/abs/2505.00080

Earth has only one moon, the Moon, but it does have smaller objects that visit the planet, complete a few orbits, and then head off into space again. Astronomers have detected four of these objects so far and performed spectroscopic analyses on them, analyzing their surface composition. They found that some of these minimoons have a composition that's very similar to the Moon, pointing to it as a major source of these temporary satellites and not the asteroid belt.

https://arxiv.org/abs/2504.17985

Helium-3 is a rare isotope emitted by the Sun, and it's very scarce in the Solar System. It's estimated that there's only one He3 atom for every 2,500 He4 atoms. But solar jets can boost the amount of He3 to 10,000 times its usual concentration. ESA's Solar Orbiter mission was recently bathed in He3, recording a 200,000-fold increase of the rare isotope because it was accelerated to higher speeds than other heavier elements by a jet emerging from a coronal hole.

https://www.swri.org/newsroom/press-releases/swri-scientists-source-solar-emissions-largest-ever-concentration-of-rare-helium-isotope

Supermassive black holes can emit powerful jets that stretch out into the cosmos, but the less massive stellar black holes can form jets too, generating beams of ionized gas that shoot outward at nearly the speed of light. Now, astronomers think they understand the underlying mechanism that generates these jets. They occur when the inner radius of the accretion disk suddenly decreases and reaches the closest point that matter can orbit without falling in.

https://www.eurekalert.org/news-releases/1079925

Gamma-ray bursts are some of the most powerful explosions in the Universe, briefly outshining the combined light of their entire galaxies. A team of astronomers has figured out a clever technique to use the light from gamma-ray bursts as bright lights that allow them to map out the large-scale structure of the Universe at different ages after the Big Bang. They found that the Universe might be less uniform at large scales than previously thought.

https://arxiv.org/abs/2504.05354

Astronomers are searching for intermediate-mass black holes, in between the stellar and supermassive varieties. Recently, a group of researchers announced the discovery of a high-velocity star rocketing out of the globular cluster M15, ejected about 20 million years ago and hurtling at 550 km/s on an escape trajectory from the Milky Way. The astronomers think this could have been caused by a three-body interaction with an intermediate-mass black hole.

https://www.eurekalert.org/news-releases/1079611

It's easy to measure the rotation rate of terrestrial planets, but the gas and ice giant planets are much more difficult, where you can't measure features on their surface directly. Instead, astronomers have relied on indirect methods, like measuring the rotation of their magnetic fields. New observations from Hubble have refined the rotation rate of Uranus with unprecedented precision, using an extremely clever method: watching the auroras complete one rotation.

https://www.esa.int/ESA_Multimedia/Images/2025/04/Hubble_helps_determine_Uranus_rotation_rate_with_unprecedented_precision

NASA's Perseverance was scanning the rim of Jezero Crater when it spotted a Martian dust devil overtake and consume another smaller one. The rover was about a kilometer away from the larger dust devil, which was about 65 meters wide. The smaller one was about 5 meters wide. This isn't Perseverance's first encounter with dust devils. It's seen clusters dancing around it and even captured audio of a dust devil on Mars for the first time.

https://www.nasa.gov/missions/mars-2020-perseverance/perseverance-rover/perseverance-rover-witnesses-one-martian-dust-devil-eating-another/

All eyes are on the Moon's south polar region, where permanently shadowed craters are protecting pockets of water ice. The ShadowCam imager, flying on Korea's Pathfinder Lunar Orbiter, can peer into these craters better than any other instrument. Planetary scientists used a machine learning algorithm to identify over a billion impact craters near the south pole, inside the shadowed craters, each larger than 16 meters in diameter.

https://www.hou.usra.edu/meetings/lpsc2025/pdf/1775.pdf