By Harrison Liao
Due to weather and communications problems, NASA’s Ionospheric Connection Explorer satellite (ICON), initially set to launch Wednesday, remained grounded for an extra day.
At first, precipitation held back Northrup Grumman’s L-1011 Stargazer aircraft, ICON’s courier into the fringes of Earth’s atmosphere where it would launch. When weather finally cleared up Thursday, aircraft communication issues prevented the launch of Pegasus XL, the rocket designed to carry ICON into orbit.
With those problems solved, ICON began its journey into orbit at around 10 p.m. EST on Thursday and hit its orbit at 39,000 feet.
It now monitors space-weather fluctuations in the Earth’s ionosphere which can impact terrestrial telecommunications systems.
What is space weather?
The launch of ICON marks the next great leap in space-weather observation.
“Space weather is much like the weather on Earth,” says NASA scientist Alex Young. “You have hurricanes and thunderstorms down here, and we get storms from the sun that interact with both the environment around the sun and the environment around the Earth.”
When energy from the sun and solar winds reach Earth’s ionosphere — the upper half of our atmosphere separating Earth from space — they react, causing red and green hues that paint the night sky.
This colorful layer of air is visible from Earth but very faint, especially around cities where light pollution is pervasive, according to Young.
What does ICON do?
That red-green tint in the sky has a name: airglow. And one of ICON’s primary missions is to record it.
ICON has a built-in device called the MIGHTI Instrument, “an interferometer that is looking down at red and green light from airglow emissions, According to Jeff Klenzing, research scientist at NASA’s Goddard Space Flight Center in Maryland.
“Airglow is basically atoms and molecules in our atmosphere changing energy states, so they’re either breaking apart and recombining with other molecules, or the electrons are being excited, dropping back down and emitting light. And they do this in very specific red-and-green bands. If we look at those red-and-green bands, we can better understand the winds and the temperature in the neutral atmosphere that is driving the atmosphere up above,” Klenzing says.
Contrary to popular belief, airglow is a separate phenomena from the Aurora Borealis.
Why is ICON important?
For starters, ICON is in many ways more effective than any ionospheric observational methods from the ground.
“ICON is going to give you another view because it is traveling around the entire Earth. So, it will not only get the area over Brazil, for instance, but look over India, over the Pacific Ocean, over places you can’t set up measurements on the ground,” Klenzing says.
And the space-weather information ICON collects is particularly relevant for one of the most important aspects of life on Earth: GPS signaling.
“Space weather is becoming more and more important because we’re relying more on technology,” Kenzling says. “Small-scale structures in the ionosphere can disturb it. Like looking through glass with a bunch of little bubbles in it, it starts to warp the image. So, if you’re talking to a GPS satellite, and you’re trying to bounce a signal off the ionosphere to the other side of the world, it’s going to start disturbing how those communications work.
These ionospheric disturbances have real-world consequences, making ICON’s role as sentry to space-weather interference ever more significant.
“Airplane navigation, precision farming,” Klenzing continues. “These are all things where you’re looking to be within centimeters of accuracy.”
Telecommunications satellites in general can be impacted by solar weather.
So, next time your plane takes off and lands on time, you might have ICON to thank.