There appear to be ripple circle patterns of cooler regions in the cosmic microwave background radiation. We don't know what they mean. One theory is they are evidence of a cyclic universe... a previous big crunch before the big bang.

Pictures & videos available on site(s).

If the theory is correct, the cosmic rings may be the first real-world evidence that our current universe is just the latest in an endless string of recycled universes, the study authors say. (Related: "Universe Reborn Endlessly in New Model of the Cosmos.")

Astronomers found the circular patterns in a new analysis of the cosmic microwave background (CMB), which is the radiation left over from the big bang that now permeates the universe.

Within the newly described rings, many of which are nested like ripples in a pond, the temperature is more uniform than elsewhere in the CMB sky. (See pictures of other odd rings and spirals in space.)

One possible explanation for these rings is that they were created when black holes collided in a previous universe, according to Roger Penrose of the University of Oxford in the U.K. and Vahe Gurzadyan of the Yerevan Physics Institute in Armenia.
Space Circles Are Proof of a Pre-Big Bang Universe?

Here's another article...

What is Cosmic Microwave Background Radiation?

CMBR is a relic of the birth of our Universe, when the entire cosmos was filled with hot plasma. The plasma emitted strong electromagnetic radiation, but as the Universe grew, this radiation lost energy as it traveled through the expanding void. Like a rubber sheet being stretched, the fabric of space-time expanded, stretching the radiation itself.

Over billions of years, this primordial radiation was red-shifted so much by universal growth that it's become nothing more than a background echo of microwave noise. But it's there, everywhere, and it can be measured.

The CMBR provides strong evidence of a Big Bang (i.e., everything came from a compressed, hot state) and universal inflation (i.e., the rapid expansion of the Universe immediately after the Big Bang).

Although instruments such as NASA's Wilkinson Microwave Anisotropy Probe (WMAP) have measured slight temperature variations in the CMBR -- known as anisotropies (pictured below) -- revealing startling clues as to the structure, age and history of the Universe, this new controversial discovery suggests the CMBR contains something else.

ANALYSIS: Mission Complete! WMAP Fires its Thrusters for the Last Time
Cosmic Rebirth Encoded in Background Radiation? : Discovery News