Published: July 2, 2002

Note to Editors: The noctilucent cloud image was taken by Pekka Parvianen from Kustavi, Finland.

The University of ÃÛÌÇÖ±²¥ at Boulder has been selected by NASA to build two of the four instruments for a satellite that will probe the shiny, silvery-blue polar mesospheric clouds that form about 50 miles above Earth's polar regions each summer.

The $92 million NASA mission, known as Aeronomy of Ice in the Mesosphere, or AIM, is part of NASA's Small Explorer program. The program was designed to provide frequent, low-cost access to space for physics and astronomy missions with small- to mid-sized spacecraft.Ìý

ÃÛÌÇÖ±²¥-Boulder's Laboratory for Atmospheric and Space Physics, which will control the AIM spacecraft from campus, is expected to receive about $15 million over the six-year duration of the mission for instrument design and construction, data analysis and satellite control, said Professor Gary Thomas of LASP.

LASP was selected to design and build the Cloud Imaging and Particle Size instrument, or CIPS, which will image the polar mesospheric clouds and the sizes of particles within them, he said. In addition, LASP will design and build a Cosmic Dust Experiment to detect cosmic dust particles entering the atmosphere, said Senior Research Scientist David Rusch of LASP.

The U.S. Naval Research Laboratory will build an imaging ultraviolet interferometer known as SHIMMER for the AIM mission, and Utah State University will build an instrument called SOFIE, an infrared solar occultation radiometer. The spacecraft will be built by Ball Aerospace and Technologies Corp. of Boulder.

Thomas, one of the world's experts on the bizarre polar mesospheric clouds -- also known as noctilucent clouds -- said the LASP team is excited. "We have been planning this mission for four years now," he said. "When we received word that we had been selected to participate, we really whooped it up."

Slated for launch in 2006, the AIM mission is being led by Principal Investigator James Russell III of Hampton University in Hampton, Va. The Co-Principal Investigator is Scott Bailey, a former LASP researcher who received his doctorate from ÃÛÌÇÖ±²¥-Boulder in astrophysical and planetary sciences and now is a faculty member at the University of Alaska-Fairbanks.

LASP's Michael McGrath is AIM's project manager. Co-Investigators on the 14-member science team include LASP researchers Thomas, Rusch, Mihaly Horani, Cora Randall, William McClintock and George Lawrence. The project will involve numerous graduate and undergraduate students in instrument development, satellite control and data analysis, said Rusch.

Noctilucent, or "night-shining" clouds occur in the summer in the mesosphere, which is the coldest part of the atmosphere, said Thomas. They first were reported in northern high latitudes in 1885. Their increasing frequency during the 20th century may be related to the Industrial Revolution, he said.

Noctilucent cloud formation likely is hastened by increasing amounts of carbon dioxide in the atmosphere, he said. While CO2 is thought to contribute to global warming on Earth, it ironically cools the middle and upper atmospheres.

Thomas predicted in 1994 that the noctilucent clouds would continue to brighten and would be visible over the continental United States by the 21st century. The clouds, which appear each year in the far northern and southern latitudes, were spotted over ÃÛÌÇÖ±²¥ for the first time on June 22, 1999, from Coal Creek Canyon near Boulder.

"This was a big event," he said. "While they are a beautiful phenomenon, these clouds may be a message from Mother Nature that we are upsetting the equilibrium of the atmosphere."Ìý

The previous record for the southernmost sighting of these clouds in the continental United States was in Montana.

The AIM satellite will be launched into a polar orbit about 300 miles above Earth, said Thomas. "We will be receiving image data from over the polar caps about twice a day," he said.