The Oldest Light in the Universe
News story originally written on February 14, 2003

A full-sky map of the oldest light in the universe. Colors indicate "warmer" (red) and "cooler" (blue) spots. The oval shape is a projection to display the whole sky; similar to the way the globe of the earth can be represented as an oval. Click on image for full size (72K JPEG) Image courtesy NASA/WMAP Science Team

NASA scientists have taken a "snapshot" picture of the oldest light in the universe. The image shows the remains of light emitted during the big bang, which is now microwave energy. The light is over 13 billion years old!

The image was created using data from a spacecraft called the Wilkinson Microwave Anisotropy Probe (WMAP). WMAP was launched in June 2001, and will collect data for 3 more years. Scientist has used data from WMAP to make the best measurement so far of the age of the universe. According to the scientists, the universe is 13.7 billion years old, plus or minus one percent. They were surprised to learn that the first stars to shine in the universe ignited only 200 million years after the big bang, which is much earlier than they expected.

A full-sky map of the oldest light in the universe. Colors indicate "warmer" (red) and "cooler" (blue) spots. The oval shape is a projection to display the whole sky; similar to the way the globe of the earth can be represented as an oval. Click on image for full size (72K JPEG) Image courtesy NASA/WMAP Science Team

NASA scientists have taken a "snapshot" picture of the oldest light in the universe. The picture shows what is left of light given off during the big bang. The light is over 13 billion years old! This old light has lost energy over the years, and is now microwave radiation.

The picture was made using data from a spacecraft called WMAP. WMAP measured the age of the universe. Scientists now think the universe is about 13.7 billion years old. Data from WMAP also tells us that the first stars started to shine about 200 million years after the big bang. That is much earlier than scientists expected.

A map of the oldest light in the universe. Warm areas are red and cooler areas are blue. Click on image for full size (72K JPEG) Image courtesy NASA/WMAP Science Team

NASA scientists have taken a "snapshot" picture of the oldest light in the universe. The picture shows what is left of light given off during the big bang. The light is over 13 billion years old! The old light has turned into microwave radiation, like the energy used to cook in a microwave oven.

The picture of the old light was made by a spacecraft called WMAP. WMAP measured the age of the universe. Scientists now think the universe is almost 14 billion years old. WMAP also shows that the first stars started to shine about 200 million years after the big bang. That is much earlier than scientists expected.