Four eyes on the sky

The four Auxiliary Telescopes at ESO’s Paranal Observatory can be seen gazing up to the night sky in this Picture of the Week. With dark and pristine skies, Paranal is one of the best places on Earth to study the universe from. As seen in this spectacular image, the view is really full to the brim of exciting things to look at. 

For instance, take a closer look to the right of the Milky Way band, at the two clouds that look like galactic fireworks. These are the Large and Small Magellanic Clouds, dwarf galaxies that are trapped by the gravity of the Milky Way. In the Mapuche language in south-central Chile they are known as lafken, labken or künchalabken (“the lagoons”), and also rünanko (“the water wells”). [1]

Peering closer to the horizon we see subtle shades of green and red, but what is it? This is called airglow and is faint light emitted atoms and molecules in the atmosphere. This can happen through various mechanisms, like interaction with solar radiation or chemical reactions between molecules. Green airglow comes from oxygen atoms, whereas the red one is due to both oxygen atoms and hydroxyl molecules. Check this ESO cast to learn more about how airglow is created and why Chile is a particularly good place to see it.


[1] Source: Wenumapu. Astronomía y Cosmología Mapuche, Gabriel Pozo Menares & Margarita Canio Llanquinao


ESO/Juan Carlos Muñoz Mateos

About the Image

Release date:14 November 2022, 06:00
Size:9307 x 4261 px

About the Object

Name:Auxiliary Telescopes, Large Magellanic Cloud, Small Magellanic Cloud
Type:Unspecified : Technology : Observatory : Telescope
Local Universe : Galaxy : Size : Dwarf

Image Formats

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