Video Transcript: Planck Exposes Ancient Light of Our Universe
The Planck mission was designed to measure the cosmic microwave background better than it's ever been measured before. It sees light from stars, from star-forming regions and galaxies. It sees light from electrons in the Milky Way.
We can remove that light from the image. It sees radio emissions from the Milky Way.
We take that light out. It sees light from dust in the Milky Way.
We can remove that light. When we take all of those other sources of light away, we're left with the cosmic microwave background itself --the oldest light in the universe, traveling towards us for 13.8 billion years and showing us the universe in its infancy.