A scarlet cosmic sea

In this colorful Picture of the Week we see a portion of the Gum 10 nebula through the eyes of ESO’s Very Large Telescope  in Chile. Gum 10 was discovered by the Australian astronomer Colin Stanley Gum, who in 1955 published a catalogue with more than 80 similar diffuse nebulae.

The energetic ultraviolet radiation from the hot blue stars in Gum 10 ionise the gas in the nebula, stripping electrons away from their atoms. When these electrons combine again with the atoms, they emit light at very specific colours or wavelengths. The red shade in this image comes from hydrogen, the most abundant element in the Universe. The dark areas are dense clouds of dust that partially block our view of the objects behind them.

This image, taken with the FORS2 instrument, was created as part of the ESO Cosmic Gems programme, an outreach initiative to produce images of interesting, intriguing or visually attractive objects using ESO telescopes, for the purposes of education and public outreach. The programme makes use of telescope time that cannot be used for science observations. All data collected may also be suitable for scientific purposes, and are made available to astronomers through ESO’s science archive.