What is cosmic microwave background radiation?
Q: What is cosmic microwave background radiation?
A: Cosmic microwave background radiation (CMB radiation) is a type of electromagnetic radiation in the microwave part of the spectrum that comes from all directions in outer space. It is believed to originate from our earliest infant universe.
Q: How do we know that CMB light arrives as the oldest signal?
A: We know that CMB light arrives as the oldest signal because the universe is very large, and the speed of light is constant. Therefore, when it reaches us from the infant universe, it has been traveling for a long time without hitting anything.
Q: Who first detected CMB radiation?
A: Arno Penzias and Robert Wilson were the first to detect CMB radiation.
Q: What evidence does its existence provide for Big Bang theory?
A: The existence of CMB radiation provides important evidence, along with red shift data, that supports Big Bang theory.
Q: What was Planck spacecraft designed to observe?
A: The Planck spacecraft was designed to observe differences in cosmic microwave background at microwave and infra-red frequencies with high sensitivity and small angular resolution.
Q: What unexpected findings have been discovered by researchers analyzing data from Planck spacecraft?
A: Researchers analyzing data from Planck spacecraft have found an asymmetry in average temperatures on opposite hemispheres of sky which runs counter to predictions made by standard model that Universe should be broadly similar in any direction we look. Furthermore, they also found a cold spot extending over a patch of sky much larger than expected which currently has no explanation.
