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If our Solar System seems stable, it's because our short lifespans make it seem that way. Earth revolves, night follows day, the Moon moves through light and shadow, and the Sun hangs in the sky. But in reality, everything is moving and influencing everything else, and the fine balance we observe can easily be disrupted. Could passing stars have disrupted Earth's orbit and ushered in dramatic climatic changes in our planet's past?

In 1912, astronomer Victor Hess discovered strange, high-energy particles called "cosmic rays." Since then, researchers have hunted for their birthplaces. Today, we know about some of the cosmic ray "launch pads", ranging from the Sun and supernova explosions to black holes and distant active galactic nuclei. What astronomers are now searching are sources of cosmic rays within the Milky Way Galaxy. One such source is a pulsar wind nebula sending high-energy particles out to space.

Great, another potential long-term risk of spaceflight. Researchers have studied the effects of simulated microgravity on mice and found that it could lead to periodontitis, where the gums become inflamed and the bones supporting teeth start to break down. This was compared to mice who experienced normal gravity. This could be limited to just the teeth or a larger indicator of inflammation in the body caused by weightlessness, which could have other health impacts.

Shortly after astronomers detected asteroid 2024 YR4 on December 27th, 2024, they realized it posed no threat to Earth. But it still might impact the Moon in 2032. The impact debris could threaten satellites and trigger an extraordinarily stunning meteor shower.

Very massive stars (VMSs), which typically has masses about 100 times that of our own Sun, are critical components in our understanding of the formation of important astronomical structures like black holes and supernovae. However, there are some observed characteristics of VMSs that don’t fit the expected behavior based on the best models we have of them. In particular, they hover around a relatively limited band of temperatures, which are hard to replicate with typical stellar evolution models. A new paper from Kendall Shepherd and their co-authors at the Institute for Advanced Study (SISSA) in Italy describes a series of new models based on updated solar winds that better fit the observations of VMSs in their natural environment, and might aid in our understanding of the development of some of the most fascinating objects in the Universe.

LUNAA Journeys (St. LUcia National Astronomy Association) is looking to address an all too common problem in the global astronomical community. Too often, participation in astronomy is seen as cost prohibitive, the sole pursuit of large universities or organizations that can afford to build a large modern observatory, or launch the Hubble Space Telescope. This is unfortunate, as there’s never been an era of more readily accessible information, out there in terms of astronomy and skywatching.

During its commissioning phase, NASA's [*Polarimeter to Unify the Corona and Heliosphere*](https://science.nasa.gov/blogs/punch/) (PUNCH) mission captured high-resolution images of a [Coronal Mass Ejection](https://www.swpc.noaa.gov/phenomena/coronal-mass-ejections) (CME) in greater detail than was previously possible.

Solar sails are space's ultimate free ride, they 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 have cracked it though with "smart mirrors" that can instantly switch their reflectivity on command, transforming sunlight from an unruly force into a precision steering tool.

The early universe was shrouded in darkness. Just hundreds of millions of years after the Big Bang, a thick fog of hydrogen gas choked the cosmos, blocking light from traveling far. At some point, this gas became ionized, stripped of its electrons. Thanks to the James Webb Space Telescope, astronomers have identified the culprit: low-mass starburst galaxies emitting huge amounts of ultraviolet light. In just one patch of sky. They discovered 83 of these galactic powerhouses in one part of the sky at a time when the Universe was only 800 million years old.

An international team of astronomers using the [*Cosmology Large Angular Scale Surveyor*](https://sites.krieger.jhu.edu/class/) (CLASS) [reported the first-ever measurement](https://hub.jhu.edu/2025/06/11/telescopes-look-at-cosmic-dawn/) announced the first-ever detection of radiation from the cosmic microwave background (CMB) interacting with the first stars in the Universe.

We don't know what dark matter is, but that doesn't stop astronomers from using it to their advantage. Dark matter is part of what makes gravitational lensing so effective. Astronomers expect the Roman Space Telescope to find 160,000 gravitational lenses, and dark matter makes a crucial contribution to these lenses.

When astronauts finally reach Mars, they'll face a unique challenge: walking and working in gravity that's only 37% as strong as Earth's. After spending months in the weightlessness of space, their weakened muscles and bones will struggle to cope with even this reduced gravity. Now, researchers at the University of Bristol have developed a promising solution; a soft, wearable exosuit powered by inflatable "bubble muscles."

When the Apollo astronauts landed on the Moon, they discovered drifts of tiny brilliant orange glass beads glittering across the surface. Each one less than 1 mm across and formed about 3.6 billion years ago. These microscopic treasures, each smaller than a pinhead, had been hiding their secrets for billions of years. Now, cutting edge technology has finally cracked the mystery: they're perfect time capsules from the Moon's explosive volcanic past, frozen droplets of ancient lava that solidified instantly in the airless void recording the history of the Moon.

The Hubble Deep Field revolutionised astronomy by staring at a seemingly empty patch of sky for thousands of hours, unveiling a cosmos teeming with distant galaxies. But even Hubble can't peer back far enough to witness the universe's first moment of illumination; the Cosmic Dawn, when primordial darkness gave way to starlight. Now, the Square Kilometre Array promises to shatter that barrier. In a groundbreaking simulation, researchers have modelled 1000 hours of SKA observations, creating astronomy's next great deep field, one designed to capture the universe's very first sunrise.

The ecliptic is the apparent path that the Sun follows during a year. It's an imaginary line that the planets follow, with some small deviations, around the Sun. Spacecraft find it easier to follow the ecliptic because it's generally more energy efficient. However, the Solar Orbiter isn't on the ecliptic and it's giving us our first up-close looks at the Sun's poles.

For most of us, dust is just something we have to clean up. For astronomers, interstellar dust is a hindrance when they want to study distant objects. However, recent James Webb Space Telescope (JWST) observations of a distant galaxy are changing that. This infrared-sensitive observatory is letting them find a way to use dust to understand the evolution of early galaxies. In addition, it uncovered a special property of that galaxy's ice-covered dust, indicating it could be similar to the materials that formed our Solar System.

Most scientists agree that supernova explosions have affected Earth's climate, though the details are not all clear. They likely cooled the climate several times in the last several thousand years, just as humanity was becoming established around the world. The evidence is in telescopes and tree rings.

Astronomers have used JWST to study a fascinating planetary system that's only 16.7 million years old, with two bizarre giant exoplanets. Designated YSES-1, its closer planet, YSES-1b seems to be surrounded by a disk of material that could be the birthplace of moons, similar to what might have happened at Jupiter billions of years ago. The other, YSES-1c, has a layer of silicate particles in its upper atmosphere—clouds of sand.

Astronomers have discovered the site of a newly forming exoplanet, probably with several times the mass of Jupiter. The image was captured by ESO's Very Large Telescope, seeing the young star system 2MASS 1612 in infrared light. The disk extends about 130 astronomical units from the star, but you can see a bright ring followed by a gap at about 50 AU. It's believed there's a new planet forming in that gap, pulling in material from the disk of gas and dust around it.

As worldwide temperatures continue to rise and conventional solutions aren't working fast enough, governments may turn to geoengineering solutions. One idea is to place a giant sunshade somewhat like an umbrella between the Earth and the Sun to block some of the sunlight that reaches our planet. A new mission proposes sending an 81 m² sail to Earth-Sun L1 to measure the effect of blocking a tiny fraction of solar energy.