Astronomy Picture of the Day

Explanation: This beautiful cosmic cloud is a popular stop on telescopic tours of the constellation Sagittarius. Eighteenth century cosmic tourist Charles Messier catalogued the bright nebula as M8, while modern day astronomers recognize the Lagoon Nebula as an active stellar nursery about 5,000 light-years distant, in the direction of the centre of our Milky Way Galaxy. Striking details can be traced through this remarkable picture, processed to reveal the Lagoon's range of filaments of glowing hydrogen gas and dark dust clouds along with the brighter, turbulent hourglass region at the upper right. The view is a colour composite of narrow and broad band images recorded under dark skies in northwestern Arizona. At the Lagoon's estimated distance, the picture spans about 30 light-years.