After contributing to many important findings on the boundary between Earth’s atmosphere and space — an area where space weather can interfere with both satellites and communications signals — NASA’s ICON (Ionospheric Connection Explorer) mission has come to an end. The mission launched in October 2019 and completed its two-year mission objectives in December 2021, before going on to operate as an extended mission for another year.
On Nov. 25, 2022, the ICON team lost contact with the spacecraft. Communication with the spacecraft could not be established, even after performing a power cycle reset using a built-in command loss timer. Though the spacecraft remains intact, other troubleshooting techniques were unable to re-establish contact between the ICON spacecraft and mission operators.
On Nov. 25, 2022, NASA’s Ionospheric Connection Explorer (ICON) team lost contact with the spacecraft. The ICON spacecraft is equipped with a built-in onboard command loss timer that will power cycle or reset the spacecraft after contact is lost for eight days. On Dec. 5, after the power cycle was complete, the team was still unable to acquire a downlink signal from the spacecraft. The team is currently still working to establish a connection.
Working with the Department of Defense’s Space Surveillance Network, the team has verified that ICON remains intact.
The ICON mission team is working to troubleshoot the issue and has narrowed the cause of the communication loss to problems within the avionics or radio-frequency communications subsystems. The team is currently unable to determine the health of the spacecraft, and the lack of a downlink signal could be indicative of a system failure.
ICON launched on Oct. 10, 2019, and completed its two-year prime mission science objectives in December 2021. It has been operating in extended mission status since that time.
On June 22, NASA’s ICON team released scientific data collected during the spacecraft’s first eight months in orbit to the public.
The data release features observations from ICON’s four instruments — MIGHTI, FUV, EUV, and IVM — which have been observing the ins and outs of the ionosphere, the sea of charged particles high in the upper atmosphere. Scientists have been busy parsing the wealth of observations collected by ICON in preparation for the mission’s first science results, which will be released later this year.
“ICON was designed, built, and launched to provide data we had never seen before, and it has not disappointed us in any regard,” said Thomas Immel, ICON principal investigator at University of California, Berkeley. Immel said he was pleased to share ICON’s first data with the world. “The sensitivity and precision of our observations, and the unique orbit and mission design, give us a new and advanced tool for unlocking all the puzzling questions we have had about the connection between Earth’s atmosphere and our space environment.”
The release coincides with the virtual summer meeting of CEDAR, the Coupling, Energetics, and Dynamics of Atmospheric Regions program. The newly released data spans measurements made since the mission’s launch on Oct. 10, 2019. Data can be accessed through University of California Berkeley’s Space Sciences Lab.
ICON observes what’s happening at the lowest boundary of space, from about 55 miles up to 360 miles above the surface. ICON explores the connections between the neutral atmosphere and the electrically charged ionosphere. In addition to interfering with communications signals, space weather in this important slice of the atmosphere can also prematurely decay spacecraft orbits and expose astronauts to radiation-borne health risks.
“We’re really excited to see the first data appearing from the ICON mission,” said Scott England, the ICON project scientist at Virginia Tech in Blacksburg, Virginia. “For me, the real power of these data isn’t just seeing transformative things like the wind patterns throughout the whole upper atmosphere, but having all these observations available to us at once, so we can see the connections between the neutral and charged environment around Earth.”
By Lina Tran NASA’s Goddard Space Flight Center, Greenbelt, Md.
Northrop Grumman’s L-1011 Stargazer aircraft, with the company’s Pegasus XL rocket attached beneath, takes off from the Skid Strip runway at Cape Canaveral Air Force Station in Florida on Oct. 10, 2019. NASA’s Ionospheric Connection Explorer (ICON) is secured inside the rocket’s payload fairing. The air-launched Pegasus XL was released from the aircraft at 9:59 p.m. EDT to start ICON’s journey to space. Photo credit: NASA/Frank Michaux
A Northrop Grumman Pegasus XL rocket launched NASA’s Ionospheric Connection Explorer, or ICON, satellite at 9:59 p.m. EDT on Oct. 10 from Cape Canaveral Air Force Station (CCAFS) to study the dynamic zone in our atmosphere where terrestrial weather from below meets space weather from above.
The satellite was attached to the Pegasus XL rocket, which hitched a ride on the company’s L-1011 Stargazer aircraft. Once the aircraft reached an altitude of 39,000 feet, the rocket was dropped, with ignition occurring five seconds after.
“This is a fun launch. In my operational function, this is about as good as it gets,” said Omar Baez, launch director in NASA’s Launch Services Program. “The anxiety level is higher, the adrenaline is flowing, but what a cool way to fly.”
Originally targeting a 9:30 p.m. drop, NASA and Northrop Grumman determined to bypass the first drop attempt due to a loss of communication between ground teams at CCAFS and the Stargazer.
NASA’s Ionospheric Connection Explorer (ICON) is attached to the Northrop Grumman Pegasus XL rocket inside Building 1555 at Vandenberg Air Force Base in California on Sept. 10, 2019. Photo credit: NASA/Randy Beaudoin
“When your launch pad is moving at 500/600 miles per hour, things happen,” said Baez. “The first attempt got us because we lost positive communication with the aircraft and the ground, and our rule is to abort the flight and go back around and try it again. And we were able to execute it flawlessly.”
The region of space where ICON will conduct its study – the ionosphere – comprises of winds that are influenced by many different factors: Earth’s seasons, the heating and cooling that takes place throughout the day, and bursts of radiation from the Sun. This region also is where radio communications and GPS signals travel, and fluctuations within the ionosphere can cause significant disruptions to these critical technologies.
As a response to the recent scientific discovery that the ionosphere is significantly impacted by storms in Earth’s lower atmosphere, Northrop Grumman designed, integrated and tested the ICON satellite under a contract from the University of California Berkeley’s Space Sciences Laboratory. NASA’s Launch Services Program at Kennedy is responsible for launch service acquisition, integration, analysis and launch management.
The ICON mission is part of NASA’s Explorer Program managed by the agency’s Goddard Space Flight Center in Maryland for the Science Mission Directorate in Washington, which aims to provide frequent flight opportunities for small- to medium-sized spacecraft that are capable of being built, tested and launched in a shorter period of time.
ICON is expected to improve the forecasts of extreme space weather by utilizing in-situ and remote-sensing instruments to survey the variability of Earth’s ionosphere. The mission also will help determine the physics of our space environment, paving the way for mitigating its effects on our technology, communications systems and society.
Learn more about NASA’s ICON mission and mission updates at:
This illustration depicts NASA’s Ionospheric Connection Explorer, or ICON, satellite that will study the frontier of space: the dynamic zone high in our atmosphere where terrestrial weather from below meets space weather from above. Photo credit: NASA
The Pegasus XL rocket has gone through each of its three stage motors, reaching a top speed of nearly 17,000 mph. ICON has now separated from the rocket to begin its mission, orbiting 360 miles above the Earth.
Following first stage separation, the second stage motor ignited 1 minute and 34 seconds after launch, burning for 1 minute, 14 seconds before shutting down and separating. At 7 minutes, 18 seconds after launch, the third stage engine ignited and will burn for 1 minute and 9 seconds.
A Northrop Grumman Pegasus XL rocket is attached to the company’s L-1011 Stargazer aircraft. Secured inside the rocket’s payload fairing is NASA’s Ionospheric Connection Explorer, or ICON, satellite. Photo credit: NASA
We have ignition! Northrop Grumman’s Pegasus XL rocket is delivering ICON, NASA’s Ionospheric Connection Explorer satellite, on its journey to the boundary between Earth and space where terrestrial weather from below meets space weather from above.
After reaching 39,000 feet, the rocket was dropped from the underside of the Northrop Grumman L-1011 Stargazer aircraft about 50 miles east of Daytona Beach, Florida.
The rocket’s first stage motor has fired, accelerating the rocket to over 5,000 miles per hour. After 1 minute and 18 seconds, the first stage motor will separate from the rest of the rocket, leaving the second and third stages to power ICON to its destination.
Northrop Grumman’s L-1011 aircraft, Stargazer, is making its way back to the drop box – a 40-mile long area that the company’s Pegasus XL rocket can be dropped in. Secured in the rocket’s payload fairing in NASA’s Ionospheric Connection Explorer (ICON) – a satellite developed to study the Earth’s ionosphere, where terrestrial weather from below meets space weather above.
The first launch opportunity of a Pegasus XL rocket, carrying NASA’s Ionospheric Connection Explorer (ICON), was skipped due to communication issues between the ground team at Cape Canaveral Air Force Station in Florida and Northrop Grumman’s L-1011 aircraft, Stargazer. The launch team is re-evaluating; the launch window remains open until 10:55 p.m. EDT.
The Northrop Grumman Pegasus XL rocket, carrying NASA’s Ionospheric Connection Explorer (ICON), has arrived at the Skid Strip at Cape Canaveral Air Force Station in Florida on Oct. 1, 2019. The rocket is attached beneath the company’s L-1011 Stargazer aircraft. ICON will study the frontier of space – the dynamic zone high in Earth’s atmosphere where terrestrial weather from below meets space weather above. Photo credit: NASA/Ben Smegelsky
Northrop Grumman’s Stargazer aircraft, carrying the company’s Pegasus XL rocket with NASA’s Ionospheric Connection Explorer (ICON), has entered the drop box – a 40-mile long area that the rocket can be dropped in. At this point, Stargazer has reached the required altitude of 39,000 feet.
In just a few moments, the rocket will drop from the aircraft. Following the drop, the rocket will freefall for about five seconds before its first stage motor ignites.
