The Milky Way's Black Hole is Spinning as Fast as it Can

Simulation of glowing gas around a spinningblack hole. Credit: Chris White, Princeton University

Pick any object in the Universe, and it is probably spinning. Asteroids tumble end over end, planets and moons rotate on their axes, and even black holes spin. And for everything that spins, there is a maximum rate at which it can rotate. The black hole in our galaxy is spinning at nearly that maximum rate.

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JWST Confirms the Formation of Heavy Elements in a Kilonova

Image from JWST’s Near-Infrared Camera (NIRCam) instrument displaying GRB 230307A’s kilonova and its former home galaxy, the former of which was found to possess heavy elements. (Credit: NASA, ESA, CSA, STScI, A. Levan (IMAPP, Warw), A. Pagan (STScI))

A recent study published in Nature investigates recent observations from NASA’s James Webb Space Telescope (JWST) and ground-based telescopes of heavy elements within the ejected material of a recent gamma-ray burst (GRB), classified as GRB 230307A, that was likely produced by a kilonova with GRB 230307A being designated as the second-brightest GRB ever detected. The heavy element in question is the chemical element tellurium, which is classified as a metalloid on the periodic table. However, scientists also hypothesize that the element iodine, which is a requirement for most of life on the Earth and classified as a reactive nonmetal, could also exist within the kilonova’s explosion, with both elements residing side-by-side on the periodic table.

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What a Mess. When the Milky Way and Andromeda Merge, it'll Look Like This

This mess is the billion-year-old aftermath of a double spiral galaxy collision. At the heart of this chaotic interaction, entwined and caught amid the chaos, is a pair of supermassive black holes — the closest such pair ever recorded from Earth. The image was taken by Gemini South, one half of the International Gemini Observatory. Credit: International Gemini Observatory/NOIRLab/NSF/AURA

No need to panic, but the Andromeda Galaxy is barreling towards us. It is due to begin merging with the our Milky Way Galaxy in a few billion years. From an outside observer, that process will very likely look like this new picture captured by the Gemini South Observatory. This is NGC 7727, a peculiar galaxy in the constellation Aquarius, about 90 million light-years away. Two giant spiral galaxies are merging, their gravitational interactions are hurling giant tidal tails of stars into the cosmos.

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JWST Takes a Detailed Look at Jupiter’s Moon Ganymede

Juno captured this image of Ganymede in July 2022. Now the JWST is taking a look at our Solar System's largest moon. Image Credit: NASA/JPL-Caltech/SwRI/MSSS/Kevin M. Gill

Nature doesn’t conform to our ideas of neatly-contained categories. Many things in nature blur the lines we try to draw around them. That’s true of Jupiter’s moon Ganymede, the largest moon in the Solar System.

The JWST took a closer look at Ganymede, the moon that’s kind of like a planet, to understand its surface better.

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Mars Still Has Liquid Rock Near its Core

An artist's depiction of the liquid silicate layer wrapped around the Martian core. Credit: IPGP-CNES.

Why doesn’t Mars have a magnetic field? If it did, the planet would be protected from cosmic radiation and charged particles emitted by our Sun. With a magnetic field, perhaps the Red Planet wouldn’t be the dry, barren world it is today.

It has long been believed that Mars once had a global magnetic field like Earth does, but somehow the iron-core dynamo that generated it must have shut down billions of years ago.

But new seismic data from NASA’s InSight lander might change our understanding of Mar’s interior, as well as alter the view of how Mars evolved and changed over time. InSight’s data revealed the presence of a molten silicate layer overlying Mars’ metallic core. Scientists say this insulating layer is like a blanket that might prevent the core from producing a global magnetic field.

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An Exo-Neptune Beat the Odds and Kept its Atmosphere

An artist impression of exoplanet LTT9779b orbiting its host star. Credit: Ricardo Ramírez Reyes (Universidad de Chile)

As planet-hunting scientists find more and more planets, they’ve encountered some puzzles. One of them concerns the lack of Neptune-size worlds orbiting close to their stars. Astronomers think that these planets aren’t massive enough to retain their atmospheres in the face of their stars’ powerful radiation, which strips it away.

But at least one of these planets has retained its atmosphere. How?

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What’s Inside the Carina Pillars? Massive Protostars and Newly-Forming Planets!

Dust Pillars in the Carina Nebula. Astronomers are peering inside Carina's pillars to get new details about starbirth activities. Credit: NASA, ESA, and the Hubble Heritage Project (STScI/AURA) Acknowledgment: M. Livio (STScI) and N. Smith (University of California, Berkeley)
Dust Pillars in the Carina Nebula. Astronomers are peering inside Carina's pillars to get new details about starbirth activities. Credit: NASA, ESA, and the Hubble Heritage Project (STScI/AURA) Acknowledgment: M. Livio (STScI) and N. Smith (University of California, Berkeley)

Star-forming nebulae are busy places. Unfortunately, clouds of gas and dust usually hide the action. To cut through the dust in one such region, a team of astronomers used the Atacama Large Millimeter Array (ALMA). They peered inside the Pillars of the Carina Nebula and studied molecular outflows (or jets) emanating from objects in this famous star-birth nursery.

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Io has 266 Active Volcanic Hotspots Linked by a Global Magma Ocean

NASA’s Galileo spacecraft captured this image of a volcanic eruption on Io in 1997. Image Credit:NASA, NASA-JPL, DLR

Jupiter’s Io stands apart from the Solar System’s other moons, with its numerous volcanoes and its surface dominated by lava flows. Io’s surface volcanism was confirmed in 1979 when the Voyager spacecraft imaged it, but its volcanic nature isn’t duplicated anywhere else in our system. Tidal heating is behind the moon’s eruptive nature, driven by Jupiter’s powerful gravity, and by resonance with other moons. But is there a magma ocean inside Io?

A final answer to that question has been elusive, but new research supports the idea of a magma ocean.

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After DART Smashed Into Dimorphos, What Happened to the Larger Asteroid Didymos?

NASA/Johns Hopkins APL.

NASA’s DART mission (Double Asteroid Redirection Test) slammed into asteroid Dimorphos in September 2022, changing its orbital period. Ground and space-based telescopes turned to watch the event unfold, not only to study what happened to the asteroid, but also to help inform planetary defense efforts that might one day be needed to mitigate potential collisions with our planet.

Astronomers have continued to observe and study Dimorphos, well past the impact event. However, Dimorphos is the smaller asteroid in this binary system, and is just a small moon orbiting the larger asteroid Didymos.

The James Webb Space Telescope (JWST) is the only telescope capable of visually distinguishing between the two closely orbiting asteroids. Now, astronomers have made follow-on observations on the system with JWST to see what happened to Didymos after the dust cleared.

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This Photonic Crystal Bends Light Like a Black Hole

Regular and distorted photonic crystals. Credit: K. Kitamura et.al

One of the first observational tests of general relativity was that the path of light bends in the presence of mass. Not only refracts the way light changes direction as it enters glass or other transparent materials, but bends along a curved bath. This effect is central to a range of physical phenomena, from black holes to gravitational lensing to observations of dark matter. But because the effect is so tiny on human scales, we can’t study it easily in the lab. That could change in the future thanks to a new discovery using distorted photonic crystals.

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