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> NGC 7023 (The Iris Nebula) in Cepheus

NGC 7023 (The Iris Nebula) in Cepheus

author: Sebastian Voltmer/Novapix

reference: a-neb70-23012

Image Size 300 DPI: 13 * 10 cm

The bright star HD 200775 shining through the nebula NGC 7023 is a 10 solar mass star centrally imbedded in a region surrounded by ambient molecular cloud material. Suns are born from vast clouds of dust and gas that gather in the dark places between the stars. Gravity causes these interstellar vapors to collapse inward until the pressure causes high enough temperatures at its center to fuse hydrogen, the universe's basic building block, into helium - an event that also releases gamma-ray photons. These photons can take a million years to travel outward through the overlying matter until they reach the surface and escape into space as visible light. The push of the photon's rush to make an exit also stops the cloud's collapse and thus what began as thin gas and dust becomes a brilliant star illuminating the heavens and possibly warming near-by planets. This picture shows a place in deep space where these kinds of events have occurred. The brilliant star near the center of the picture is young and very hot- in relative terms, it was only recently created. The cloud from which it formed still surrounds this young Sun but is being blown away by the push of star's massive radiation. This picture shows the way it looked 1,300 years ago due to the distance that separates it from Earth and the speed that light travels.

Keywords for this photo:

2009 - ASTRONOMY - CEPHEUS - IRIS - MASSIVE STAR - NEBULA - NGC 7023 - REFLECTION NEBULA - STAR - STAR CLUSTER -