Foregrounds
The most important foreground components of the CIB are the following:
- Zodiacal emission: the thermal emission of microscopic dust particles in the Solar System (from near- to mid-infrared)
- Thermal emission of small asteroids in the Solar System (from near- to mid-infrared)
- Galactic cirrus emission (far-infrared)
- Faint Galactic stars (in the near-infrared, λ<20μm)
- Infrared emission of intracluster dust in the Local Group
- The cosmic microwave background - although physically it is not a "foreground" - is also considered as an important contaminating source of emission at very long infrared wavelengths (λ>300μm)
These components must be separated for a clear CIB detection.
Read more about this topic: Cosmic Infrared Background