Page 16 - Curriculum Visions Dynamic Book

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 This Hubble space telescope picture shows part of the Eagle Nebula (M16; NGC 6611) 7,000 ligHt-years from Earth in the constellation Serpens. When we look at a picture like this, we see the Universe as it was 7,000 years ago, not as it is today.
It shows newborn stars emerging from dense, compact pockets of interstellar gas called evaporating gaseous globules (EGGs).
The EGGs are at the tip of fingerlike features made of cold hydrogen gas and dust that stick out from the wall of a vast cloud of the same material. Each finger is several light- years long.
The interstellar gas is dense enough to collapse under its own weight, forming young stars that continue to grow as they suck in more and more mass from their surroundings.
The newborn stars send out a flood of ultraviolet light, causing much of the surrounding hydrogen to evaporate (the process is called photoevaporation). The photoevaporation disperses the cloud made by the EGG and leaves the stars revealed as isolated objects in space.
Red shows light emitted by sulfur atoms. Green shows light emitted by hydrogen atoms. Blue shows light emitted by oxygen atoms.