Astronomy

Astronomers have performed the deepest radio observations ever of Omega Centauri, searching for signs of an intermediate mass black hole thought to lurk at its center. Despite 170 hours of observations with the Australia Telescope Compact Array achieving unprecedented sensitivity, they detected absolutely nothing where the black hole should be. If an intermediate mass black hole exists in this massive star cluster, as suggested by fast moving stars discovered earlier this year, it must be accreting material at an extraordinarily low rate, barely feeding at all compared to other known black holes.

Researchers have discovered that a close encounter with a rogue planet or brown dwarf during the Sun's early years could have triggered the reshuffling of our Solar System's giant planets. Running 3000 simulations of stellar flybys, the team found that substellar objects passing within 20 astronomical units of the young Sun could destabilise the planets' orbits just enough to match their current configuration without destroying the delicate Kuiper belt. This flyby scenario represents a new possible explanation for one of the Solar System's defining events, with roughly a 1-5 percent probability depending on how common free floating planets actually are in young star clusters.

Astronomers at the University of Tokyo have used gravitational lensing to measure how fast the universe is expanding, adding weight to one of cosmology's most intriguing mysteries. Their technique exploits the way massive galaxies bend light from distant quasars, creating multiple distorted images that arrive at different times. The measurement supports recent observations showing the universe expands faster than predictions based on the early universe suggest, strengthening evidence that the "Hubble tension" represents genuine new physics rather than experimental error.

Researchers using NASA’s James Webb Space Telescope have detected the strongest evidence yet for an atmosphere on a rocky planet outside our solar system. Observations of the ultra-hot super-Earth TOI-561 b suggest that the exoplanet is surrounded by a thick blanket of gases above a global magma ocean.

Carl Sagan famously said that “We’re all made of star-stuff”. But he didn’t elaborate on how that actually happened. Yes, many of the molecules in our bodies could only have been created in massive supernovae explosions - hence the saying. Scientists have long thought they had the mechanism for how settled - the isotopes created in the supernovae flew here on tiny dust grains (stardust) that eventually accreted into Earth, and later into biological systems. However, a new paper from Martin Bizzarro and his co-authors at the University of Copenhagen upends that theory by showing that much of the material created in supernovae is captured in ice as it travels the interstellar medium. It also suggests that the Earth itself formed through the Pebble Accretion model rather than massive protoplanets slamming together.

The U.S.’s and Denmark’s health systems are starkly different, so it makes sense that their vaccination schedules would differ, too

The early universe was a very different place than today. And by “early” I don’t mean a billion or even ten billion years ago. The universe is about 13.77 billion years old, and when it was only a handful of seconds old, it was completely unrecognizable.

On December 5, 2022,

Northern Fox Fires

Large galaxies grow by eating small ones.

Sculpted by stellar winds and radiation, this dusty interstellar

Many wonders are visible when flying over the Earth at night.

What would it be like to fly over the

A new study, analyzing over 1,600 galaxies observed with Chandra over two decades, suggests that smaller galaxies do not contain supermassive black holes nearly as often as larger galaxies do.

Christmas trees—and conifers in general—have made some surprising cameos throughout U.S. history, author Trent Preszler reveals in his book Evergreen

In the early 20th century, after years of effort, Albert Einstein developed his general theory of relativity. This was a massive improvement in our understanding of gravity, giving us a sophisticated view into the inner workings of that fundamental force.

General-purpose robots remain rare not for a lack of hardware but because we still can’t give machines the physical intuition humans learn through experience

Tracking down resources on the Moon is a critical process if humanity decides to settle there permanently. However, some of our best resources to do that currently are orbiting satellites who use various wavelengths to scan the Moon and determine what the local environment is made out of. One potential confounding factor in those scans is “space weathering” - i.e. how the lunar surface might change based on bombardment from both the solar wind and micrometeroid impacts. A new paper from a researchers at the Southwest Research Institute adds further context to how to interpret ultra-violet data from one of the most prolific of the resource assessment satellites - the Lunar Reconnaissance Orbiter (LRO) - and unfortunately, the conclusion they draw is that, for some resources such as titanium, their presence might be entirely obscured by the presence of “old” regolith.