Universe Today

Stephen Hawking has made a compelling case that black holes eventually evaporate, but the time scales are beyond our ability to detect it. A new paper suggests that primordial black holes passing through the Solar System could be releasing positron emissions that would be detectable when they pass up to 10 AU from Earth. If found, they would confirm Hawking's theories and provide an explanation for dark matter. Unfortunately, our best technology isn't quite sensitive enough.

The Chinese Space Agency took a major step toward its 2030 lunar mission goals this week by successfully testing the escape system of its next-generation Mengzhou spacecraft. At the Jiuquan Satellite Launch Center, engineers conducted their first zero-altitude escape flight test at 12:30 PM when solid rocket engines ignited, propelling the spacecraft skyward for 20 seconds before the return capsule separated, deployed parachutes, and landed safely.

As different nations begin conducing operations on the lunar surface, humanity's penchant for geopolitical struggles will likely be along for the ride. Tension between nations and/or corporations could grow. There are few rules and treaties that can calm this potential rising tension. What kinds of conflict might erupt and how can it be prevented?

Star formation peaked during the Cosmic Noon, which spanned from 10 to 12 billion years ago. During Cosmic Noon, star formation was 10 to 100 times greater than it is now. New research shows that a particular class of galaxy was experiencing its first intense burst of star formation during this time. Were these galaxies the progenitors of galaxies like the Milky Way?

Modern telescopes like the Zwicky Transient Facility (ZTF) are watching the sky for any changes, and can report a million variations in a single night. This will multiply when Vera Rubin comes online. SETI researchers are looking for specific events that could be caused by an intelligent civilization, and have developed methods to search through astronomical alerts automatically. This could give SETI researchers dozens of potential targets a night to follow up on, scanning for signals or anomalous changes in brightness.

You're probably aware that most of the matter of the Universe is "dark matter," and astronomers still don't know what it is. But 75% of the regular matter in the Universe is also hidden, located in the thin gas between galaxies. Probing this gas is difficult, but astronomers have used a new technique, analyzing the light from fast radio bursts as they pass through billions of light-years of gas. Longer, redder wavelengths are slowed down compared to shorter, bluer wavelengths, allowing the hidden material to be weighed.

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.

Black holes can accumulate planets and stars' worth of material, but even they have their limits. Astronomers have discovered a supermassive black hole which has reached that limit. Excess material is now being ejected from the vicinity around the black hole at nearly a third the speed of light. Astronomers found that about 10 Earth masses of material were added to the black hole's vicinity in 5 weeks, creating a ring of matter and feeding the outflow jets.

The Vera C. Rubin is a game changing observatory that we've been keeping our eyes on. When it goes online, it'll begin a 10 year survey of the southern sky, capturing the entire sky every few nights, eventually building up a history of 800 images of each spot. It'll generate 20 terabytes of data every day, collecting 60 petabytes of raw image data. And it's almost ready to begin operations. On June 23 at 15:00 UTC, operators are going to release the first images from the telescope live to the internet, and you'll be able to watch.

When the Apollo astronauts returned to Earth, they complained that the gritty lunar dust got into everything, including their lungs. There have been decades of research into its toxicity, and a recent study has shown that it might actually be less hazardous than regular Earth-based air pollution. Sure, it can cause irritation to lung tissue, but not that kind of severe cellular damage or inflammation seen from urban Earth dust. It doesn't seem to cause long-term diseases like silicosis.

Hycean worlds are planets covered in oceans that also have thick hydrogen atmospheres. There are no confirmed Hycean worlds—also called ocean worlds—but many candidates. Even though they're only candidates so far, researchers are curious about their habitability. New research examines the role tidal heating plays in their potential habitability.

We might not currently have any technology that would make a space elevator viable on Earth. But that doesn’t mean they wouldn’t work on other bodies around the solar system. One of the most interesting places that one could work is around Ceres, the Queen of the Asteroid Belt, and potentially one of the biggest sources of resources for humanity’s expansion into space. A new paper from researchers at the University of Colorado, Colorado Springs and Industrial CNT, a manufacturer of Carbon Nanotube (one potential material for the space elevator), details just how useful such an elevator could be.

More and more satellites are being added to Low Earth Orbit (LEO) every month. As that number continues to increase, so do the risks of that critical area surrounding the Earth becoming impassable, trapping us on the planet for the foreseeable future. Ideas from different labs have presented potential solutions to this problem, but one of the most promising, electrodynamic tethers (EDTs), have only now begun to be tested in space. A new CubeSat called the Spacecraft for Advanced Research and Cooperative Studies (SPARCS) mission from researchers at the Sharif University of Technology in Tehran hopes to contribute to that effort by testing an EDT and intersatellite communication system as well as collecting real-time data on the radiation environment of its orbital path.

A recent study looked at the challenges New Space may face, in terms of impact on the ozone layer. The study was published recently in the journal of Nature (link) by researchers out of University of Canterbury in Christchurch, New Zealand, Harvard University, and the Institute for Atmospheric Climate Science and the Physics-Meteorology Observatory in Switzerland.

With over 5,000 exoplanets now identified, astronomers have found that our Solar System isn't the only model of planetary formation. There are super-Earths, sub-Neptunes, hot-Jupiters, and Earth-sized worlds orbiting around red dwarf stars. In a new paper, researchers propose how the search for life could adapt to these bizarre environments, expanding the definition of a habitable world. Life could exist without a surface, or using different kinds of solvents than water.

The early Solar System was filled with both hydrogen and oxygen that can chemically bond into water. But did we create all the water, or was some of it inherited from the earlier times, already present in the protostellar nebula? Astronomers have used the James Webb Space Telescope to study a newly-forming protoplanetary system called L1527 IRS, which will eventually become a star like our Sun. They found evidence that water from interstellar space is preserved when it becomes part of a new star system.

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.

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.