A cloud of interstellar gas and dust that appears bright because it reflects or scatters starlight. The light from a reflection nebula has the same spectral lines as the starlight it reflects, but it is usually bluer and may be polarized. Reflection nebulae often occur together with emission nebulae in regions of recent star formation. The Pleiades cluster is surrounded by a reflection nebula.
Subjects: Astronomy and Astrophysics.