From the edge of space, NASA’s ICON satellite is transmitting images and data to science team
Earth’s ionosphere stretches from 50 to over 400 miles above the ground, where the uppermost levels of the atmosphere meet the beginning layers of space. Difficult to explore, this region is home to a mix of neutral and charged particles, and is responsive to weather patterns that ripple up from the lower atmosphere below.
Launched last autumn, NASA’s Ionospheric Connection Explorer, or ICON, mission set out to increase our understanding of the ionosphere and its potential impact on communications, GPS, and space weather prediction.
ICON launched on Oct. 10, 2019, and entered science mode on Dec. 1, which means the spacecraft has been transmitting images and data from this layer back to the primary ground station at the University of California Berkeley and backup ground stations in Wallops Island, Virginia; Chile; and Singapore.
That raw data is then distributed to each of the partner institutions within about 24 hours, which includes Virginia Tech. Scott England, associate professor in the Kevin T. Crofton Department of Aerospace and Ocean Engineering, serves as the project scientist for ICON and has been working on developing and testing the software that analyzes the raw data captured by the spacecraft.
“The software developed here at Space@VT uses both images captured by ICON and models of the atmosphere to perform calculations and help us make detailed examinations of its density, motion, temperature, and energy,” said England. “At these early stages, the entire science team is scrutinizing the processed data and discovering what these measurements really can tell us about this region of space.”
The instrumentation aboard the spacecraft includes multiple imaging systems that measure airglow, or the natural glow of the Earth’s atmosphere caused by solar radiation. The science team is using the data to track height and density of the ionosphere during both daylight hours and night, the behavior of intermingling gases in contrast to the neutral atmosphere, and the effect that winds and weather patterns in the upper atmosphere have on the region.
The team was also presented with a unique opportunity when ICON flew very close to the solar eclipse track extending across Asia in late December 2019. ICON’s instrumentation was in a prime position to observe the effects of what happens when airglow is temporarily “turned off” as the sun is blocked by the moon’s shadow. Preliminary data shows that all four instruments were able to detect changes the eclipse wrought.
“It was exciting to see the impact the eclipse had on these airglow layers, the upper atmosphere, and the ionosphere,” said England. “During transitions from daylight into night, we see the airglow become dimmer. Throughout the eclipse, the region that is in shadow is so much smaller and the airglow responded at a different rate. By carefully measuring that rate, we are able to test our understanding and models in a way that we can’t test them at day and night boundaries.”
ICON will continue to make observations over the next two years, greatly increasing our understanding of this relatively unexplored region.
At Space@VT, the Virginia Tech students involved in the NASA project included Christopher Krier, who is pursuing a doctoral degree in aerospace engineering; and Zhikun "Ace" Wu, a senior majoring in aerospace engineering.
Written By Jama Green