A dark figure spreads its wings against a star background: The "Cosmic Bat" nebula has been captured in beautiful detail by the European Southern Observatory (ESO).
The cosmic Batan, formally known as NGC 1788, is two thousand light years away in a dark corner of the Orion constellation. The nebula does not give off any light, because it is what is called a "reflection nebula" which means that there is a cloud of dust and gas as it only illuminates the light from nearby stars. As for the board, the lighting comes from a cluster of young stars in its core.
To capture this dimenebula, a powerful telescope is required. ESO used its very large telescope (VLT), part of the Paranal observatory in the Atacama desert in Chile, located at a high altitude – 2,635 m above sea level. The site has very low levels of light pollution, as the nearest community to the observatory is the small village of Paposo, the population 259, which is 38 kilometers away.
This means that the VLT can capture very dim or very distant phenomena that use their 8.2m diameter mirrors, with minimal blurring caused by the Earth's atmosphere.
This particular image of the cosmic cat is the most detailed image of the nebula ever taken since it was first cataloged by astronomer William Herschel in 1888. It was chosen as a target for imaging to celebrate the twentieth anniversary of one of ESO's instruments, FOcal Reducer and Low Dispersion Spectrograph 2 (FORS2).
The FORS2 instrument, mounted on one of the VLT's telescope, is a versatile tool that can take spectra of one of several objects simultaneously. As a spectroscope, it can spread the light in a rainbow of different wavelengths to allow astronomers to study the chemical composition of distant objects. And it can also form large parts of the sky with high sensitivity, creating beautiful images like this one of the cosmic Bat.