The European Southern Observatory (ESO) has released a staggeringly detailed visible light image of the famous Cat's Paw and Lobster nebulae, made up of around two billion pixels. Officially called NGC 6334 (Cat's Paw) and NGC 6357 (Lobster), the nebulae are located in the "tail" of the constellation Scorpius, and represent regions of intense star formation.
The pair were first discovered on consecutive nights in June 1837 by the renowned British scientist John Herschel, as he undertook a three-year expedition to the Cape of Good Hope in South Africa.
In the time since Herschel made his discovery, mankind's understanding of stellar nurseries has advanced at an astonishing pace. We now know that NGC 6334 & NGC 6357 belong to a family of nebulae known as emission nebulae.
An emission nebula gets its name from the faint infrared glow emitted by hydrogen atoms embedded within the cosmic clouds that form the nebula. The glow is created as youthful, yet massive stars (around 10 times the mass of our Sun), blast the surrounding interstellar material with intense ultraviolet light, causing the hydrogen atoms to become energized, and glow.
Upon discovering NGC 6334 & NGC 6357 in 1837, Herschel could only discern the brightest "footpad" of the Cat's Paw. The nebula's full majesty, and that of its nearby brethren, would not be revealed for decades to come.
Following in Herschel's early footsteps, astronomers have imaged the nebulae with numerous orbital and Earth-bound telescopes, capturing the many different aspects of the complex structures by observing them in different wavelengths of light.
The newest image of the Cat's Paw and Lobster nebulae was captured using the OmegaCam instrument mounted aboard the ESO's Very Large Telescope Survey Telescope (VST) located at the Paranal Observatory, Chile.
OmegaCam can observe across a wide wavelength range, and covers a field of view the equivalent of 256 million pixels, allowing the instrument to take images 16 times larger than those captured by the Hubble Space Telescope's Advanced Camera for Surveys (ACS).
The advanced capabilities of OmegaCam are complemented by the adaptive optics system integrated with the primary mirror of the 2.6 m (8.5 ft) VST, which makes use of 108 individual motors to manipulate the reflective surface to capture the sharpest possible image.
OmegaCam's 49,511 x 39,136-pixel image of the nebulae reveals the complex and chaotic structure of the gas that comprises NGC 6334 & NGC 6357, alongside the dense tendrils of filamentary dust that work to obscure parts of the active vista of star formation unfolding behind.
The VST and OmegaCam captured the Cat's Paw and Lobster nebulae in the visible light spectrum, which you can explore for yourself using this zoomable version of the image.
The ESO video below pans across the OmegaCam vista (video courtesy of ESO/N. Bartmann).