ESO’s VLT Survey Telescope Spots a Spooky Bat-Shaped Nebula Soaring 10,000 Light-Years Away

A new astronomical image released by the European Southern Observatory (ESO) has revealed a vast, eerily beautiful cloud of gas and dust that looks remarkably like a cosmic bat flying across the Milky Way. Captured just in time for Halloween, this striking structure—located about 10,000 light-years away—is a sprawling stellar nursery where new stars are being born. The image was taken using ESO’s VLT Survey Telescope (VST) at the Paranal Observatory in Chile’s Atacama Desert, one of the best observing sites on Earth.

A Cosmic Bat Spanning the Skies

The newly released image shows a massive region of glowing hydrogen gas, dark filaments of dust, and brilliant young stars spread across an area of the sky roughly equivalent to four full moons. The structure’s shape—resembling an outstretched bat—emerges from a vast cloud complex situated between the southern constellations Circinus and Norma.

Two of the most prominent nebular clouds in the region, RCW 94 and RCW 95, form the key features of this cosmic silhouette. RCW 94 appears as the right wing of the bat, while RCW 95 forms its body. The remaining “wing” and peripheral structures have no official designations, but together, they create an unforgettable view of a galactic creature mid-flight.

What makes the nebula stand out visually is its intense red glow, caused by ionized hydrogen atoms. The radiation from the young, massive stars embedded within the cloud excites these hydrogen atoms, making them shine brilliantly in the visible spectrum. The darker threads running through the nebula are dense lanes of gas and dust—regions cold enough to block background starlight—giving the structure its haunting, skeletal appearance.

The Instruments Behind the Discovery

The VLT Survey Telescope (VST), owned and operated by the Italian National Institute for Astrophysics (INAF) and hosted by ESO, is specially designed to capture wide-field views of the night sky. Unlike many telescopes that zoom in on small patches of the cosmos, the VST’s broad coverage makes it ideal for imaging large-scale structures like nebulae.

At the heart of the telescope is OmegaCAM, a 268-megapixel digital camera that can capture vast swaths of the heavens in remarkable detail. For this particular image, astronomers combined observations taken through multiple filters—each allowing only specific wavelengths of light to pass. This technique reveals subtle details about the temperature, density, and composition of the interstellar material.

Most of the image comes from data gathered as part of the VST Photometric Hα Survey of the Southern Galactic Plane and Bulge (VPHAS+), which focuses on mapping hydrogen-alpha light across the southern Milky Way. To enhance the view, astronomers also added infrared observations from ESO’s Visible and Infrared Survey Telescope for Astronomy (VISTA), which operates at the same site in Paranal. The infrared data, obtained through the VISTA Variables in the Vía Láctea (VVV) survey, reveal the denser, dustier regions of the nebula that are invisible in optical light.

The combination of visible and infrared wavelengths paints a complete picture—showing both the glowing clouds ionized by young stars and the hidden regions where new stars are still forming.

A Stellar Nursery in Action

The cosmic bat is not just a pretty shape—it’s a stellar nursery, a place where new stars are born from collapsing clouds of gas and dust. Inside, gravity pulls matter together into increasingly dense clumps. When the pressure and temperature rise high enough, nuclear fusion begins, and a new star ignites. These newborn stars emit intense ultraviolet radiation that ionizes the surrounding hydrogen gas, creating the characteristic red glow seen in the image.

The dark filaments in the nebula are equally important. These are regions where the dust is so thick that it absorbs visible light, making them appear like silhouettes against the luminous background. In these cooler, denser areas, the next generation of stars may already be taking shape. Such filaments are often the sites of protostar formation, where matter gathers in cocoons that will eventually shine as new suns.

Where It Is and How Far

Located between the constellations Circinus and Norma, the nebula lies roughly 10,000 light-years from Earth, deep within the plane of our Milky Way Galaxy. This is an active region of star formation, rich in hydrogen gas and dust. The vast scale of the object makes it appear as if a bat is gliding through the interstellar medium, stretching its wings across the galactic sky. From our perspective, it occupies a surprisingly large patch—four times the diameter of the full moon—though its immense distance keeps it faint and ghostly to the unaided eye.

ESO’s Paranal Observatory and the Power of Surveys

The Paranal Observatory, where the VST and VISTA are located, is one of the world’s premier astronomical facilities. Perched in the Atacama Desert of northern Chile, it benefits from extraordinarily dry air, minimal light pollution, and clear skies nearly all year round. Alongside the VST, the observatory hosts the Very Large Telescope (VLT), a set of four 8.2-meter telescopes capable of detailed observations across the electromagnetic spectrum.

The VPHAS+ and VVV surveys conducted at Paranal are open to the global research community and the public. These projects aim to map vast portions of the Milky Way, cataloging nebulae, star clusters, and variable stars. The “cosmic bat” image is part of this effort—both a scientific observation and a stunning piece of cosmic art.

Why Astronomers Love Wide-Field Images

Wide-field imaging surveys like VPHAS+ and VVV are essential for understanding large-scale patterns in our galaxy. While high-resolution telescopes zoom in on specific stars or planets, wide-field surveys show context—how stars form in clusters, how gas clouds interact, and how large structures evolve over time.

For instance, mapping hydrogen-alpha light helps astronomers identify active regions of star formation and measure how radiation from massive stars affects the interstellar environment. Infrared surveys complement this by revealing the hidden, dust-enshrouded stages of the star-forming process that optical light cannot penetrate.

Seeing Shapes in the Stars

The bat-like form is, of course, a coincidence—an example of pareidolia, where the human brain recognizes familiar patterns in random or complex visuals. Astronomers and enthusiasts often give whimsical names to nebulae based on such resemblances: the Horsehead Nebula, the Eagle Nebula, and now, the Cosmic Bat. These names not only make celestial objects easier to remember but also help spark public curiosity about astronomy.

Still, behind the imaginative nickname lies a serious object of study. The physical processes shaping these clouds—stellar winds, magnetic fields, and gravitational forces—tell astronomers about the life cycles of stars and the evolution of galaxies.

The Bigger Picture

This discovery highlights the growing role of large-scale sky surveys in modern astronomy. With instruments like the VST and VISTA, scientists can gather massive datasets that reveal how stars are distributed and how nebulae evolve over time. Every new image, like this bat-shaped cloud, adds another piece to the cosmic puzzle of how our galaxy builds and renews itself.

For now, the cosmic bat continues to glide silently through the Milky Way, its wings illuminated by the energy of newborn stars—an appropriately spooky sight for an October discovery.

Research Source: ESO Press Release – “A Spooky Bat Signal in the Sky” (eso2518)