The Iris Nebula, also known as NGC 7023 or Caldwell 4, is a beautiful reflection nebula located in the constellation Cepheus. Unlike emission nebulae that produce their own light, the Iris Nebula glows because it is illuminated by a central, hot, young star, HD 200775, which is surrounded by a cloud of interstellar dust.
The Iris Nebula, also known as NGC 7023 or Caldwell 4, is a beautiful reflection nebula located in the constellation Cepheus. Unlike emission nebulae that produce their own light, the Iris Nebula glows because it is illuminated by a central, hot, young star, HD 200775, which is surrounded by a cloud of interstellar dust.