NGC 7023: The Iris Nebula
Image Credit &
Copyright:
Tony Hallas
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.