Asked by Barrie Schofield
These are protoplanetary discs, pancakes of dust and gas around young stars, which make up planets, located some 1,500 light years away from Earth.
These discs are made mostly of gas but even a small amount of dust is able to make the discs appear opaque and dark at the wavelengths visible to the human eye. The discs also appear dark because they are silhouetted against the bright backdrop of hot gas, which comprises the famous star- forming region.
There’s usually a red glow to be seen at the centre of these discs, which is a newly-formed star, roughly one million years old and can be anywhere from 30 to 150 per cent of the mass of the Sun.
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