The University of Colorado at Boulder has been selected by NASA to
design and build an instrument package for a new satellite known the
Solar Dynamics Observatory, the first mission in the agency’s new
“Living with a Star” program.

CU-Boulder’s Laboratory for Atmospheric and Space Physics will
receive roughly $29 million over the next 11 years from NASA to
design and integrate a suite of instruments for the Solar Dynamics
Observatory, or SDO, to study extreme ultraviolet radiation from the
sun, said LASP Senior Research Scientist Tom Woods. The LASP
experiment, which will consist of six instruments, is known as the
Extreme Ultraviolet Variability Experiment, or EVE.

“EVE should help us understand the sun and the output of extreme
ultraviolet radiation, which has direct effects on Earth,” said
Woods, the principal investigator of the LASP experiment. “It should
provide information on space weather above 30 miles in altitude, one
of the regions where the solar output can affect satellite

Slated for launch in 2007, the six-year-long SDO mission will measure
the sun’s dynamics to increase understanding of the nature and
sources of solar variability, said Woods. The EUV radiation in
particular – the most variable part of the solar spectrum — can
change by a factor of 1,000 at some wavelengths over time scales of
minutes to years.

Although it never reaches Earth’s surface, EUV from the sun is known
to hinder both Earth’s space-to-ground and ground-to-ground
communications, especially during high solar activity, he said.

It also can produce temperature and chemical changes in the upper
atmosphere tied to the natural production and depletion of nitric
oxide and ozone in the mesosphere and thermosphere located from 30
miles to 300 miles above Earth, Woods said.

EVE will consist of three LASP spectrographs that will measure EUV
radiation at three different ranges in the electromagnetic spectrum,
said Woods. Each will be attached to a charged-coupled device to
enhance observing power. In addition, the University of Southern
California will provide a spectrometer for the payload, as well as
two spectrophotometers to collect photons of EUV light.

The satellite will be launched in a geosynchronous orbit about 22,000
miles high, providing measurements of solar radiation 24 hours a day,
said Woods. Data will be downloaded continuously to NASA’s Goddard
Space flight Center in Greenbelt, Md., then transmitted to LASP’s
Space Technology Building at the CU Research Park in close to
real-time for analysis.

The EVE Science Team at LASP also includes Project Scientist Frank
Eparvier and Co-Investigators Gary Rottman and Don Woodraska. The
CU-Boulder project will involve about 40 LASP engineers and 40

The students, primarily undergraduates, will participate in all
phases of the project, including the design, testing, calibration and
day-to-day operations of EVE from LASP’s Research Park facility. The
students also will be heavily involved in data analysis during the

“On most of the space missions or instruments we control from campus,
we have about one contact a day,” said Woods. “But with our
experiment on EVE, we will have contact 24 hours a day.” The
satellite will orbit Earth once each day because of its
geosynchronous orbit.

NASA’s new “Living with A Star” program is a space-weather focused
and application-driven research program to develop the scientific
understanding needed to address sun-Earth connections that directly
affect life and society.