Nebula
A nebula is a giant cloud of gas (mostly hydrogen and helium) and cosmic dust situated between stars in the interstellar medium. Nebulae serve as sites of stellar birth and death—including emission nebulae that glow from ionized gas, reflection nebulae that scatter starlight, and dark nebulae that obscure background stars.
Source: science.nasa.gov
APODs including "Nebula"
Carina Pillar and Jets
01/10/2009
This cosmic pillar of gas and dust is nearly 2 light-years wide. The structure lies within one of our galaxy's largest star forming regions, the Carina Nebula, shining in southern skies at a distance of about 7,500 light-years. The pillar's convoluted outlines are shaped by the winds and radiation of Carina's young, hot, massive stars. But the interior of the cosmic pillar itself is home to stars in the process of formation. In fact, placing your cursor over this visible light image will reveal a penetrating near-infrared view of the pillar - now dominated by two, narrow, energetic jets blasting outward from a still hidden infant star. Both visible light and near-infrared images were made using the Hubble Space Telescope's newly installed Wide Field Camera 3.