This computer drawing shows MAP leaving the Sun, Earth and Moon behind as it heads towards the L2 Lagrange point 1.5 million kilometers beyond Earth.
Click on image for full size
Courtesy of the MAP Science Team, NASA

Capturing the Afterglow of the Big Bang
News story originally written on June 25, 2001

According to the Big Bang theory, the universe began about 12-14 billion years ago. Right after the Big Bang, the universe was really hot! But, as the universe has expanded, the particles within the universe have cooled. There is a radiation that fills the universe, called Cosmic Microwave Background Radiation (CMB). CMB radiation is literally the remnant heat left over from the Big Bang.

The CMB radiation that can be tracked today is very cool; it is only ~2.73 degrees Kelvin (degrees above absolute zero). CMB radiation is everywhere! If we could see in the microwave segment of the electromagnetic spectrum, we would see CMB radiation everywhere! And the CMB radiation would glow with a brightness that was almost uniform across the whole universe!

The MAP (Microwave Anisotropy Probe) will be launched June 30, 2001. It is so precise that it will be able to measure differences in cosmic microwave background radiation even better than the COBE probe before it. Anisotropy simply means measuring the differences in temperature from cosmic microwave background radiation from different directions. So, radiation from one part of the sky might be 2.7251 degrees Kelvin and radiation from another part of the sky might be 2.7249 degrees Kelvin. MAP can measure differences even to a millionth of a degree! "Nothing has ever been built like it before," said Dr. Edward Wollack, a science team member at Goddard. "To measure the cosmic glow reliably to a part in a million, to millionths of a degree has been the grand challenge. That's like measuring the weight of a cup of sand down to the resolution of a single grain."

"The cosmic microwave light is a fossil," says Professor David T. Wilkinson, Princeton University, Princeton, NJ. "Just as we can study dinosaur bones and reconstruct their lives of millions of years ago, we can probe this ancient light and reconstruct the Universe as it was about 14 billion years ago." By mapping CMB radiation emission, scientists are hoping to see into the past so that they might answer questions such as these: What happened during the first instant after the Big Bang? How did the universe evolve into the complex patterns of galaxies that we see today? Will the universe expand forever or will it collapse? Is the universe dominated by exotic dark matter? What is the shape of the universe?

The MAP probe will be launched on a Delta II rocket from Cape Canaveral, FL. It will swing past the Earth 3-5 times and then swing past the Moon, using the Moon's gravity to maneuver to the L2 Lagrange point. MAP will reach the L2 point in about 3 months. While remaining in orbit around the L2 point, 1.5 million kilometers from Earth, the probe will take about 18 months to do a full-sky survey of CMB radiation.

Last modified June 25, 2001 by Jennifer Bergman.

You might also be interested in:

Traveling Nitrogen Classroom Activity Kit

Check out our online store - minerals, fossils, books, activities, jewelry, and household items!...more


The introduction of telescopes to the study of astronomy opened up the universe, but it took some time for astronomers to realize how vast the universe could be. Telescopes revealed that our night sky...more

1999--A Year in Review...

It was another exciting and frustrating year for the space science program. It seemed that every step forward led to one backwards. Either way, NASA led the way to a great century of discovery. Unfortunately,...more

STS-95 Launch: "Let the wings of Discovery lift us on to the future."

The Space Shuttle Discovery lifted off from Kennedy Space Center at 2:19 p.m. EST, October 29th. The sky was clear and the weather was great as Discovery took 8 1/2 minutes to reach orbit for the Unitied...more

Moon Found Orbiting Asteroid

A moon was discovered orbiting the asteroid, Eugenia. This is only the second time in history that a satellite has been seen circling an asteroid. A special mirror allowed scientists to find the moon...more

U.S. is Fed Up with Russia

Will Russia ever put the service module for the International Space Station in space? NASA officials are demanding an answer from the Russian government. The necessary service module is currently waiting...more

More on Recent Coronal Mass Ejection

During a period of about two days in early May, 1998, the ACE spacecraft was immersed in plasma associated with a coronal mass ejection (CME). The SWICS instrument on ACE, which determines unambiguously...more

Mother Nature's Air Conditioning

J.S. Maini of the Canadian Forest Service has referred to forests as the "heart and lungs of the world." Forests reduce soil erosion, maintain water quality, contribute to atmospheric humidity and cloud...more

Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA