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The Universe may be nearly 27 billion years old — and it may not need dark matter What if the cosmos is not 13.8 billion years old, but almost twice that age? Scientists from the University of Ottawa — Rajendra Gupta and Nikolaos Samaras — have presented new arguments for a model that stretches the age of the Universe to 26.7 billion years and does so without dark matter or dark energy. The model is called CCC+TL. It rests on two unusual assumptions. First: the fundamental physical constants are not entirely constant — they change gradually as the cosmos evolves. Second: the “tired light” hypothesis, according to which photons gradually lose energy as they travel across vast distances. Together, these mechanisms offer an alternative way to explain the redshift of distant galaxies, usually attributed to the expansion of space. The model has already passed several serious tests. It was able to reproduce the proportions of light elements (hydrogen, helium, and others) that formed shortly after the Big Bang — one of the main pillars of standard cosmology. This requires, however, that the rates of nuclear reactions and neutron decay change in step with the expansion of the Universe. Under that condition, the match is very precise. Another test involved the rotation curves of 175 galaxies from the SPARC catalog. The “extra” speed of stars and gas is usually explained by dark matter. CCC+TL described the same curves without it, with roughly the same quality as the popular alternative MOND. Even the famous Bullet Cluster, where ordinary matter and gravitational mass are separated, the model attempted to explain without dark matter (though the authors themselves call this a preliminary result). The most striking advantage concerns what the James Webb Space Telescope has seen. It found galaxies that are too massive and mature for an era when, according to standard calculations, the Universe was only a few hundred million years old. In the CCC+TL model, at the same redshift, the age of the cosmos can reach about 4.6 billion years. Galaxies would have had far more time to grow — in some estimates their masses and sizes turn out to be roughly 12 times larger than in the conventional picture. However, the model has already faced objections. An analysis of 32 measurements of the expansion rate using cosmic chronometers showed that the CCC+TL parameters fitted to supernovae do not match these data well — standard cosmology performs better. Gupta replied that methods for determining galaxy ages rely on ordinary physics and must be applied to his model with corrections. The discrepancy has not yet been fully resolved. A major test remains: the cosmic microwave background. The standard model describes its temperature fluctuations with high accuracy. Gupta claims his approach can also handle it, but detailed results have not yet been published. The idea of an older Universe was proposed by Gupta back in 2023. It is now being tested against new data, including future observations of the most distant galaxies. For now, CCC+TL remains an interesting alternative rather than a ready replacement for conventional cosmology. To seriously revise the age of the Universe, the model will need to provide a consistent explanation for the full range of astronomical observations — from the first light elements to the microwave background.

The sky that suddenly stopped being eternal November 1572. The constellation Cassiopeia. On what seemed like an ordinary night, a star flares up in a place where no star had ever been. It shines so brightly that it remains visible even in the daytime against the pale autumn sky. For people of that era, this was not just an astronomical event. It was a blow to their entire picture of the world. The stars were believed to be unchanging and perfect — an eternal sphere untouched by earthly change. And yet here, right before everyone’s eyes, a “new star” appeared and broke all the rules. The German astronomer Wolfgang Schuler was the first to notice it, on November 6, 1572, simply by looking up. But the outburst became truly famous thanks to the Danish astronomer Tycho Brahe. He carefully observed it, measured its position and brightness, and soon published a book titled *De nova stella* (“On the New Star”). Because of him, the event entered history as Tycho’s Supernova. The brilliant guest remained visible during the day for about two weeks and could be seen with the naked eye for a full 16 months. Gradually it faded and finally disappeared. Today we know it was SN 1572 — a classic Type Ia supernova roughly 13,000 light-years away. A white dwarf that had been pulling material from a companion star reached a critical mass and detonated. And the sky still hasn’t settled down. Right now astronomers are closely watching the star T Coronae Borealis. It may erupt at any moment as a nova — a less powerful event than a supernova, after which the star survives. But even such a flare would remind us of the same lesson Tycho’s Supernova once taught: the heavens are not eternal. They change. And sometimes they do it right before the eyes of all humanity.

Miranda: Uranus’ Most Chaotic Moon (and the Solar System’s Worst Paint Job) Meet Miranda, a 470-kilometer-wide moon of Uranus that looks like someone tried to assemble a planet and then gave up halfway through. Made of rock and ice, it’s probably the smallest object in the solar system that’s still round under its own gravity, and it appears to be differentiated. Its surface, however, is pure chaos. You’ll find a towering 20-kilometer-high cliff, strange chevron-shaped tectonic scars, and a patchwork of wildly different terrains that seem to have been stitched together at random. For years, one popular idea was that Miranda was smashed apart by a giant impact and then clumsily reassembled from the debris. The leading explanation today is gentler but still dramatic: powerful extensional forces and warm ice rising from the interior warped and resurfaced the moon, creating the bizarre, mismatched landscape we see. The only close-up views we have come from Voyager 2, which flew past on January 24, 1986, and captured this global mosaic from about 32,000 km away.