NGC 7023: The Iris
Nebula
From NASA’s Astronomy Picture of the Day
Like delicate cosmic
petals, these clouds of interstellar dust and gas have blossomed 1,300
light-years away in the fertile star fields of the constellation Cepheus.
Sometimes called the
Iris Nebula and dutifully cataloged as NGC 7023 this is not the only nebula in
the sky to evoke the imagery of flowers.
Still, this remarkable image shows off the Iris Nebula's range of colors and symmetries
in impressive detail.
Within the Iris, dusty nebular material surrounds a hot, young star. The dominant
color of the brighter reflection nebula is blue, characteristic of dust grains reflecting starlight.
Central filaments of the dusty clouds glow with a faint reddish
photoluminesence as some dust grains effectively convert the star's invisible ultraviolet radiation to visible red light.
Infrared observations indicate that this nebula may contain
complex carbon molecules known as PAHs. The bright blue portion of the Iris Nebula is
about six light-years across.
Image Credit & Copyright: Tony Hallas