One of the Oldest Astrolabes Has Both Hebrew and Arabic Markings

I always think of planispheres when I think of astrolabes! Navigators used these ancient devices (astrolabes not planispheres) to provide an accurate map of the stars in the sky. To use them you would match up the metal plates to the sky and you could calculate your location. Astrolabes date back to 220BC but one with Hebrew and Arabic markings was found and it is thought to have originated back in the 11th Century.

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Webb Sees a Surprisingly Active Galaxy When the Universe Was Only 430 Million Years Old

This JWST image shows thousands of galaxies of various shapes and colours on the black background of space. It's called the GOODS North Field. The pullout features GN-z11, an ancient and extremely luminous galaxy, seen as a fuzzy yellow dot. Image Credit: NASA, ESA, CSA, B. Robertson (UC Santa Cruz), B. Johnson (CfA), S. Tacchella (Cambridge), M. Rieke (University of Arizona), D. Eisenstein (CfA) CC BY 4.0 INT

Unlocking the mysteries of the early Universe is one of the JWST’s primary endeavours. Finding and examining some of the first galaxies is an important part of its work. One of the Universe’s first galaxies is extraordinarily luminous, and researchers have wondered why. It looks like the JWST has found the answer.

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Massive Stars Have the Power to Shape Solar Systems

This image is a Hubble image of the inner regions in the Orion Nebula, with a JWST image of a protoplanetary disk named d203-506. The disk is close enough to the massive Trapezium Cluster stars that their UV radiation is shaping the planet-forming process in the disk. Image Credit: NASA/STSCI/RICE UNIV./C.O'DELL ET AL / O. BERNÉ, I. SCHROTTER, PDRS4ALL

Stars shape their solar systems. It’s true of ours, and it’s true of others. But for some massive stars, their power to shape still-forming systems is fateful and final.

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A Giant Gamma-Ray Bubble is a Source of Extreme Cosmic Rays

An artist's depiction of a gamma-ray burst's relativistic jet full of very-high-energy photons breaking out of a collapsing star. Credit: DESY, Science Communication Lab

Gamma-ray bursts (GRBs) are one of the most powerful phenomena in the Universe and something that astronomers have been studying furiously to learn more about their origins. In recent years, astronomers have set new records for the most powerful GRB ever observed – this includes GRB 190114C, observed by the Hubble Space Telescope in 2019, and GRB 221009A, detected by the Gemini South telescope in 2022. The same is true for high-energy cosmic rays that originate from within the Milky Way, whose origins are still not fully understood.

In a recent study, members of China’s Large High Altitude Air Shower Observatory (LHAASO) Collaboration discovered a massive gamma-ray burst (designated GRB 221009A) in the Cygnus star-forming region that was more powerful than 10 peta-electronvolts (PeV, 1PeV=1015eV), over ten times the average. In addition to being the brightest GRB studied to date, the team was able to precisely measure the energy spectrum of the burst, making this the first time astronomers have traced cosmic rays with this energy level back to their source.

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How Warm Are the Oceans on the Icy Moons? The Ice Thickness Provides a Clue.

Jupiter's moon Ganymede is the largest moon in the Solar System and may have an ocean sandwiched between two layers of ice. But how warm is that ocean? Image Credit: By National Oceanic and Atmospheric Administration Public Domain, https://commons.wikimedia.org/w/index.php?curid=8070396

Scientists are discovering that more and more Solar System objects have warm oceans under icy shells. The moons Enceladus and Europa are the two most well-known, and others like Ganymede and Callisto probably have them too. Even the dwarf planet Ceres might have an ocean. But can any of them support life? That partly depends on the water temperature, which strongly influences the chemistry.

We’re likely to visit Europa in the coming years and find out for ourselves how warm its ocean is. Others on the list we may never visit. But we may not have to.

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This Planet-Forming Disk has More Water Than Earth’s Oceans

Astronomers have found water vapour in a disc around a young star exactly where planets may be forming. In this image, the new observations from the Atacama Large Millimeter/submillimeter Array (ALMA) show the water vapour in shades of blue. Image Credit: ALMA (ESO/NAOJ/NRAO)/S. Facchini et al.

Astronomers have detected a large amount of water vapour in the protoplanetary disk around a young star. There’s at least three times as much water among the dust as there is in all of Earth’s oceans combined. And it’s not spread throughout the disk; it’s concentrated in the inner disk region.

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How We Get Planets from Clumping Dust

This artist’s impression shows a young star surrounded by a protoplanetary disk, where dust grains gather together to form planetesimals—the building blocks of new planets. © ESO/L. Calçada

Our gleaming Earth, brimming with liquid water and swarming with life, began as all rocky planets do: dust. Somehow, mere dust can become a life-bearing planet given enough time and the right circumstances. But there are unanswered questions about how dust forms any rocky planet, let alone one that supports life.

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A Nova in the Making: Will T Coronae Borealis Pop in 2024?

Recurrent Nova
A recurrent nova in action. Credit NASA

If predictions are correct, a key outburst star could put on a show in early 2024.

If astronomers are correct, a familiar northern constellation could briefly take on a different appearance in 2024, as a nova once again blazes into prominence. The star in question is T Coronae Borealis, also referred to as the ‘Blaze Star’ or T CrB. Located in the corner of the constellation Corona Borealis or the Northern Crown, T CrB is generally at a quiescent +10th magnitude, barely discernible with binoculars… but once every 80 years, the star has flared briefly into naked eye visibility at around +2nd magnitude.

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Dwarf Galaxies Banished the Darkness and Lit Up the Early Universe

The JWST used gravitational lensing to search for the sources of light that triggered the Epoch of Reionization and brought darkness to an end. The white hazy blobs are galaxies in Pandora's Cluster, which acts as the gravitational lens. The red objects are the distant and ancient objects magnified by the lens, some of them warped into arcs. Many of them are early dwarf galaxies, some of them responsible for the Epoch of Reionization. Image Credit: NASA/ESA/CSA JWST

During the Universe’s Dark Ages, dense primordial gas absorbed and scattered light, prohibiting it from travelling. Only when the first stars and galaxies began to shine in energetic UV light did the Epoch of Reionization begin. The powerful UV light shone through the Universe and punched holes in the gas, allowing light to travel freely.

New observations with the James Webb Space Telescope reveal how it happened. The telescope shows that faint dwarf galaxies brought an end to the darkness.

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Planets in Binary Star Systems Could be Nice and Habitable

An AI-generated artist's concept of a planet in a binary star system where the orbits may not yet be in alignment. Credit: Michael S. Helfenbein.
An AI-generated artist's concept of a planet in a binary star system where the orbits may not yet be in alignment. Credit: Michael S. Helfenbein.

The Star Wars world Tatooine is one of the most recognizable planets in the realm of science fiction. It’s a harsh place, and its conditions shaped the hero Luke Skywalker in many ways. In the reality-based Universe, there may not be many worlds like it. That’s because, according to a new study out from Yale researchers, the Universe likes to be more orderly, and that affects planets and their environments.

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