Astronomer

A giant planet emerges from the darkness: JWST filters out starlight to reveal 51 Eridani b In astronomy, less light sometimes means more visibility. A team of astronomers has managed to "turn off" the blinding glare of the star 51 Eridani A to reveal its planet, 51 Eridani b—a gas giant with a mass roughly 11 times that of Jupiter, located about 97 light-years away. Although this exoplanet was first discovered from Earth in 2015, it had previously been lost in the star’s brilliance in images taken by the James Webb Space Telescope (JWST). Even the brightest planets are 100,000 times fainter than their host stars; observing them is akin to trying to spot a firefly next to a lighthouse. While coronagraphs can block out the star’s disk, they cannot eliminate its light entirely—residual glare and scattered light often obscure the faint signal of a planet. Typically, this "blinding" effect is mitigated by subtracting a reference image of a different star from the observation. However, even ultra-stable observatories experience minute fluctuations; for instance, the JWST’s cooled NIRCam instrument relies on cryocoolers equipped with tiny motors, and the resulting microscopic vibrations in the mirrors cause light to scatter, creating persistent artifacts or "spots" of glare. This is enough to hide even a massive world. To overcome this, researchers have proposed a new approach called FLIP (Physics-based Learning for Imaging Planets). They developed a digital "twin" of the telescope—a model that tracks exactly how starlight travels through the mirrors and reaches the detectors. The "double" was then precisely calibrated against actual observations—accounting for millions of micro-irregularities and fluctuations—to calculate exactly what kind of glare should appear in the image. Once this modeled glare was subtracted, the JWST was able to "see" what had previously been hidden. The team tested this approach using data from two systems known to host exoplanets—HIP 65426 and 51 Eridani—as well as one system with no known planets, TYC 5899. In terms of sensitivity to faint objects, the FLIP method outperformed standard techniques by a factor of 2 to 15, and the exoplanet 51 Eridani b was revealed within JWST archival data dating back two years. The authors emphasize that this is not a simulation, but rather the actual recovery of a signal that had remained "on the table"—unnoticed due to imperfect data processing.

James Webb Reveals a Galaxy That Packed Almost All Its Stars Into Tiny Clusters — Just 400 Million Years After the Big Bang 🌌 What if the first galaxies didn’t form stars gradually, but in short, furious bursts concentrated in a handful of compact knots? Using the James Webb Space Telescope, an international team led by Minami Nakane (University of Tokyo) has peered into one such object — nicknamed **Misty Moons** — as it existed only 370–410 million years after the Big Bang. Thanks to the powerful gravitational lens of the foreground galaxy cluster MACS J0257.1-2325, the light of this distant galaxy was magnified 20–30 times, allowing astronomers to resolve individual star-forming regions that would otherwise have remained invisible even to Webb. The result is striking: more than 80 % of the galaxy’s stellar mass is locked inside just a few compact clumps. These regions are tiny — effective radii of only 10–70 parsecs (roughly 33–228 light-years) — yet each already contains around 10 million solar masses of stars that are only tens of millions of years old. Dust is scarce, and the star-formation rate per unit area can be hundreds or even thousands of times higher than in today’s dwarf galaxies. In other words, Misty Moons looks less like a smoothly distributed little galaxy and more like a collection of intense stellar factories — possible early ancestors of the globular clusters we still see in the present-day Universe. The distance is still based on photometry (redshift ≈ 11–12) and awaits spectroscopic confirmation. Future observations with NIRSpec and MIRI will test whether these clumps formed inside a single system or arrived via mergers, and whether a central black hole contributes to the light. For now, Misty Moons offers a rare, magnified window into how the very first stellar systems assembled: not gradually, but in concentrated, explosive bursts of star birth.

James Webb Reveals a Galaxy That Packed Almost All Its Stars Into Tiny Clusters — Just 400 Million Years After the Big Bang 🌌 What if the first galaxies didn’t form stars gradually, but in short, furious bursts concentrated in a handful of compact knots? Using the James Webb Space Telescope, an international team led by Minami Nakane (University of Tokyo) has peered into one such object — nicknamed **Misty Moons** — as it existed only 370–410 million years after the Big Bang. Thanks to the powerful gravitational lens of the foreground galaxy cluster MACS J0257.1-2325, the light of this distant galaxy was magnified 20–30 times, allowing astronomers to resolve individual star-forming regions that would otherwise have remained invisible even to Webb. The result is striking: more than 80 % of the galaxy’s stellar mass is locked inside just a few compact clumps. These regions are tiny — effective radii of only 10–70 parsecs (roughly 33–228 light-years) — yet each already contains around 10 million solar masses of stars that are only tens of millions of years old. Dust is scarce, and the star-formation rate per unit area can be hundreds or even thousands of times higher than in today’s dwarf galaxies. In other words, Misty Moons looks less like a smoothly distributed little galaxy and more like a collection of intense stellar factories — possible early ancestors of the globular clusters we still see in the present-day Universe. The distance is still based on photometry (redshift ≈ 11–12) and awaits spectroscopic confirmation. Future observations with NIRSpec and MIRI will test whether these clumps formed inside a single system or arrived via mergers, and whether a central black hole contributes to the light. For now, Misty Moons offers a rare, magnified window into how the very first stellar systems assembled: not gradually, but in concentrated, explosive bursts of star birth.

A galactic twin of the Milky Way: meet NGC 7331 ✨ This stunning spiral galaxy is located 50 million light-years away in the constellation Pegasus, and it bears a striking resemblance to our own home in terms of both size and structure.

A Hidden Relic in the Heart of the Milky Way: A Star Cluster Nearly as Old as the Universe Buried deep in the dusty core of our galaxy lies a quiet survivor from the dawn of time. Astronomers have determined that VVV CL001, a metal-poor globular cluster near the center of the Milky Way, is roughly 13.4 billion years old. That places it among the oldest known star clusters in the Galaxy—and uncomfortably close to the age of the universe itself (about 13.8 billion years). The cluster was first spotted in 2010 during an infrared survey, but it wasn’t confirmed as a true globular cluster until nine years later. Even then, its exact distance and age remained frustratingly uncertain. Thick clouds of interstellar dust block most visible light, and the region around the galactic center is so crowded that individual stars blur together. Earlier observations simply couldn’t reach deep enough. To pierce the dust, researchers turned to near-infrared imaging with the FourStar camera on the 6.5-meter Magellan Baade telescope, combined with deep Hubble Space Telescope observations. By carefully identifying member stars—especially those on the horizontal branch and at the main-sequence turn-off—they refined both the distance and the age. The cluster sits about 7.34 kiloparsecs (roughly 24,000 light-years) away, firmly inside the galactic bulge. What makes VVV CL001 especially intriguing is its chemistry. Its stars are extremely metal-poor, containing only a tiny fraction of the heavy elements found in the Sun. That means they formed from nearly pristine gas, before successive generations of stars had enriched the interstellar medium. In other words, these are fossils from the galaxy’s earliest days. The cluster also moves with a velocity quite different from most stars in its neighborhood, yet its orbit keeps it bound to the bulge. Together, the age, low metallicity, and location suggest it formed in place during the early assembly of the proto-Milky Way rather than being captured from a smaller galaxy that was later swallowed. If the 13.4-billion-year age holds up, VVV CL001 may be the oldest globular cluster yet found in the bulge—and possibly in the entire Galaxy. Because the universe itself is only about 13.8 billion years old, any such estimate must sit below that ceiling once uncertainties are included. The researchers note that if the cluster truly formed where it is and is this ancient, it could force a rethink of how old the Milky Way (and perhaps even the universe) really is. Further high-resolution spectroscopy is planned to lock down the chemical abundances and confirm the result. For now, VVV CL001 stands as one of the most compelling candidates for the galaxy’s oldest surviving star cluster—a dusty, half-hidden relic that has been quietly orbiting the galactic center since the cosmos was still in its infancy.

Featured here is the galaxy NGC 289, captured by astrophotographer Wolfgang Promper! 🔭 The image was taken using a Ritchey-Chrétien telescope with a focal length of 6760 mm. ❕It is a barred spiral galaxy located in the constellation Sculptor.

Famous Black Hole Has Jet Pushing the Cosmic Speed Limit Deep in the Virgo Cluster, the colossal black hole at the center of galaxy Messier 87—the same one whose shadow was famously imaged by the Event Horizon Telescope—is blasting out a jet of particles at more than 99% the speed of light. NASA’s Chandra X-ray Observatory tracked bright “knots” in the jet between 2012 and 2017 and caught them racing outward. The closer knot (about 900 light-years from the black hole) shows an apparent speed of 6.3 times the speed of light; a farther one clocks in at 2.4 times light speed. These aren’t violations of physics—they’re the classic optical illusion of superluminal motion. When material is already moving extremely close to light speed and aimed roughly toward us, the light it emits later has a shorter distance to travel, compressing the timeline so the knots appear to streak across the sky impossibly fast. The real takeaway is stronger: the fading of one knot by roughly 70% in X-rays (from synchrotron cooling of the same particles) shows these are the actual particles themselves, not just a moving wave or shock. It’s the strongest evidence yet that material in M87’s jet is being accelerated right up to the ultimate cosmic speed limit. Image credit: NASA/CXC/SAO/B. Snios et al.