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The Star of Bethlehem might have actually been a comet described in an ancient Chinese text

Many researchers have spent decades attempting to decode biblical descriptions and link them to verifiable historical events. One such description is that of the Star of Bethlehem—a bright astronomical body that was said to lead the Magi to Jesus shortly after his birth.

Although many attempts have been made to link the Star of Bethlehem to astronomical bodies, the unique motion of the “star” did not quite fit any known object. However, a new research study, published in Journal of the British Astronomical Association, describes a likely candidate for the bright object seen above Bethlehem over 2000 years ago—a comet described in an ancient Chinese text.

Veritas explores the nature of a mysterious gamma-ray emitter

Astronomers have employed the Very Energetic Radiation Imaging Telescope Array System (VERITAS) to observe a mysterious gamma-ray emitting source designated HESS J1857+026. Results of the observational campaign, published December 19 on the pre-print server arXiv, shed more light on the nature of this source.

Bose-Einstein Condensate; When Atoms Act As One

Bose–Einstein Condensate (BEC) explained: Cool a dilute gas of atoms to billionths of a degree above absolute zero and they merge into one coherent matter wave—a Bose–Einstein condensate. This video covers laser cooling, magnetic/optical traps, evaporative cooling, the onset of quantum degeneracy, and why a BEC behaves like a superfluid. See signatures: interference fringes, quantized vortices, long coherence length, and frictionless flow. Applications include atom interferometers (precision gravity and rotation sensing), quantum simulation of complex materials, and space-based experiments (ISS Cold Atom Lab). We also touch on first BECs (1995, rubidium/sodium), critical temperature, and why bosons condense while fermions do not.

Behold the Manifold, the Concept that Changed How Mathematicians View Space

The world is full of such shapes—ones that look flat to an ant living on them, even though they might have a more complicated global structure. Mathematicians call these shapes manifolds. Introduced by Bernhard Riemann in the mid-19th century, manifolds transformed how mathematicians think about space. It was no longer just a physical setting for other mathematical objects, but rather an abstract, well-defined object worth studying in its own right.

This new perspective allowed mathematicians to rigorously explore higher-dimensional spaces—leading to the birth of modern topology, a field dedicated to the study of mathematical spaces like manifolds. Manifolds have also come to occupy a central role in fields such as geometry, dynamical systems, data analysis, and physics.

To unify relativity and quantum mechanics we must abandon materialism

Physicists have so far failed to unify general relativity and quantum mechanics. As attempts to unite them into a quantum theory of gravity mount up, philosopher of physics Dean Rickles argues that the assumption of materialism is the problem. We need to look beyond the physical—beyond space, time and matter—to something primordial out of which minds can construct physical reality, and which explains both general relativity and quantum mechanics. Pioneers like John Wheeler and David Bohm have already begun to chart what such a realm of “pre-physics” might look like—it’s high time physics took their ideas more seriously.

A pair of recent physics Nobel prizes (2020 and 2022) were awarded for basic research in general relativity (Einstein’s theory of gravitation that explains gravity as the curvature of spacetime by matter and energy) and quantum mechanics (our best bet for a theory of matter and energy). The experimental successes of these theories keep piling up. There is clearly much truth in them. They both aim to describe the same world: this world. They should surely overlap, since the matter and energy described by quantum mechanics should curve spacetime as well as good old-fashioned non-quantum mechanical matter and energy. Why then can we not construct a theory in which they both appear? Why is it so difficult to build what would be a Quantum Theory of Gravity?

Astronomers Finally See What Really Happens During Stellar Nova Explosions

Using Georgia State’s CHARA Array, an international team of scientists has uncovered unexpected complexity in how stars explode. Astronomers have obtained images of two stellar explosions, called novae, just days after they erupted, capturing them in detail never achieved before. These observatio

A Cosmic Christmas Tree Lights Up the Milky Way

Just in time for Christmas, a vast star-forming region shaped like a Christmas tree is lighting up space 2,700 light-years from Earth.

NGC 2,264 is a vast region of space where new stars are actively forming, located about 2,700 light-years from Earth in the faint constellation Monoceros, also known as the Unicorn. Astronomers use catalog names like NGC 2,264 to identify and track objects beyond our solar system, and this particular one stands out for its intricate mix of glowing clouds and young stars. Positioned near the celestial equator and close to the flat disk of the Milky Way, this region is visible at certain times of year from much of the world.

How young stars light up space

Uranus and Neptune are hiding something big beneath the blue

Uranus and Neptune may not be the icy worlds we’ve long imagined. A new Swiss-led study uses innovative hybrid modeling to reveal that these planets could just as easily be dominated by rock as by water-rich ices. The findings also help explain their bizarre, multi-poled magnetic fields and open the door to a wider range of possible interior structures. But major uncertainties remain, and only future space missions will The Solar System is commonly grouped by planetary composition: four rocky terrestrial planets (Mercury, Venus, Earth and Mars), two massive gas giants (Jupiter and Saturn), and a pair of ice giants (Uranus and Neptune). However, new research from a scientific team at the University of Zurich (UZH) suggests that Uranus and Neptune may contain far more rock than previously assumed. The study does not argue that these planets must be either water-rich or rock-rich. Instead, it questions the long-standing idea that an ice-heavy interior is the only conclusion supported by available data. This broader interpretation also aligns with the finding that Pluto, a dwarf planet, is dominated by rock.

To better understand what lies inside Uranus and Neptune, the researchers created a specialized simulation technique. “The ice giant classification is oversimplified as Uranus and Neptune are still poorly understood,” says Luca Morf, PhD student at the University of Zurich and lead author of the work. “Models based on physics were too assumption-heavy, while empirical models are too simplistic. We combined both approaches to get interior models that are both “agnostic” or unbiased and yet, are physically consistent.”

The process begins with a randomly generated density profile representing the interior of each planet. The team then determines the gravitational field that would match observational measurements and uses that information to infer the possible composition. The cycle is repeated until the model best fits all available data.

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