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| Northrop Grumman’s L-1011 Stargazer aircraft is on the runway at the Cape Canaveral Air Force Station Skid Strip, FL on Oct. 8, 2019. The company’s air-launched Pegasus XL rocket, containing NASA’s Ionospheric Connection Explorer, or ICON, satellite is attached to the belly beneath the aircraft as ground crews prepare for launch Oct. 9. Credit: Ken Kremer/kenkremer.com/spaceupclose.com |
KENNEDY SPACE CENTER & CAPE CANAVERAL AIR FORCE STATION, FL – NASA’s new science mission to study the Earth’s ionosphere – the tenuous upper atmospheric layer at the ‘frontier of space’ forming the dynamic boundary where Earth’s weather meets space weather – known as ICON, is tentatively slated to launch as early as this Wednesday evening, Oct. 9 from Florida - - as poor weather threatens the launch and 1 year after a last minute scrub of the air launched Pegasus XL rocket due to issues then unresolved with the rockets ability to successfully carry it to orbit.
The Northrop Grumman Pegasus XL rocket finally appears to be ready to launch NASA’s ICON science probe after being afflicted with multiple anomalies forcing multiple launch delays over the past two years – as well as a complete change in the launch site from Kwajalein Atoll in the Marshall Islands to the Florida Space Coast.
Extensive testing showed recurring issues with the Pegasus rudder system are now fixed after months of work, say NASA and Northrop Grumman officials.
The ionosphere — a dynamic region of Earth’s upper atmosphere loaded with charged and neutral particles is home to colorful auroras like the Aurora Borealis or northern lights, hundreds of critical communication satellites, and astronaut crew living 24/7 aboard the International Space Station (ISS).
“The ionosphere is continually changing, and it’s very dynamic, so that can have big impacts on our ability to do this kind of communication,” said Nicky Fox, head of NASA’s heliophysics division at NASA HQ at today prelaunch briefing at the Kennedy Space Center.
“So not only is it a great place to go and study plasma physics, but it’s also a region that has a big space weather impact on us.”
Today the media and Space Up Close participated in a tour of the rocket and L-1011 carrier aircraft at the Skid Strip launch site on Cape Canaveral Air Force Station, Tuesday, Oct. 8.
Enjoy our Space UpClose photo gallery of ICON, Pegasus XL rocket and L-1011 Stargazer direct at
the Skid Strip.
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| Up Close view of Northrop Grumman’s air-launched Pegasus XL rocket containing NASA’s Ionospheric Connection Explorer, or ICON, satellite which is attached to the belly beneath the company’s L-1011 Stargazer aircraft that will deploy the probe at 39,000 feet. Here it sits on the runway at the Cape Canaveral Air Force Station Skid Strip, FL, on Oct. 8, 2019. Launch NET Oct. 9, 2018. Credit: Ken Kremer/kenkremer.com/spaceupclose.com |
NASA’s $252 million Ionospheric Connection Explorer (ICON) research satellite mission
is nestled inside the nose cone of the Pegasus XL rocket that’s cradled at the
belly of the Northrop Grumman L-1011 carrier jet named ‘Stargazer’ – the very last of its kind
still flying in the world.
Unfortunately the weather outlook is 70% NO GO unfavorable as outlined at today’s prelaunch briefing at the Kennedy Space Center.
“With a cold front moving in and a forecast of scattered showers throughout the day, weather officials from the U.S. Air Force 45th Space Wing are currently predicting a 30% chance of favorable weather conditions for launch. Primary weather concerns are the cumulus cloud rule and lightning rule,” according to weather forecasters.
“I wish I had some better news, but ultimately, we’re going to do our best with all the tools we have at our disposal to ensure that tomorrow’s launch – or potentially Thursday night’s launch – is as safe as possible,” said Will Ulrich, launch weather officer for the U.S. Air Force 45th Space Wing, in Tuesday afternoon’s mission briefing.
“If we go to the backup day – hopefully we don’t need to have a 24-hour delay, but should we – conditions are going to be a little better,” said Ulrich. Thursday’s forecast shows less chance of rain, and weather conditions improve to a 60% chance “go” for launch.
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| Up Close view of nose cone of Northrop Grumman’s air-launched Pegasus XL rocket encapsulating NASA’s Ionospheric Connection Explorer, or ICON, satellite which is attached to the belly beneath the company’s L-1011 Stargazer aircraft that will deploy the probe at 39,000 feet. Here it sits on the runway at the Cape Canaveral Air Force Station Skid Strip, FL, on Oct. 8, 2019. Launch NET Oct. 9, 2018. Credit: Ken Kremer/kenkremer.com/spaceupclose.com |
“We’ve had some Pegasus issues and are still working on them,” Omar Baez, Sr. Launch Director, Launch Services Program, NASA Kennedy Space Center. told Space UpClose in an interview at the Skid Strip last year.
“When we brought the plane over from Vandenberg it was
powered up and we saw some signatures on the Pegasus launch vehicle that did not
make us happy. So we have taken the time
to change out some components and try to exonerate the issues - and are doing
some analysis.”
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| Up Close full view of Northrop Grumman’s air-launched Pegasus XL rocket containing NASA’s ICON satellite which is attached to the belly beneath the company’s L-1011 Stargazer aircraft that will deploy the probe at 39,000 feet. File photo from the prior launch attempt as it sat on the runway at the Cape Canaveral Air Force Station Skid Strip, FL, on Nov. 2, 2018. Launch now reset to Oct. 9, 2019. Credit: Ken Kremer/kenkremer.com/spaceupclose.com |
Originally the root cause was traced to a
faulty sensor, which was replaced. But the off-nominal data reading recurred
forcing further data reviews and launch postponements.
“The problem was with equipment in the control system - that was very similar to what we saw earlier. It’s taken more time than expected. So we are analyzing that.”
“We thought we had it licked but didn’t. So we are working the issue further to make sure it doesn’t have us licked.”
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| Up Close view of trio of rear fins on Northrop Grumman’s air-launched Pegasus XL rocket encapsulating NASA’s Ionospheric Connection Explorer, or ICON, satellite which is attached to the belly beneath the company’s L-1011 Stargazer aircraft that will deploy the probe at 39,000 feet. Here it sits on the runway at the Cape Canaveral Air Force Station Skid Strip, FL, on Oct. 8, 2019. Launch NET Oct. 9, 2018. Credit: Ken Kremer/kenkremer.com/spaceupclose.com |
The ICON spacecraft itself has been healthy throughout as reconfirmed
at today’s prelaunch briefing where I asked about the testing to ensure the probe
is ready.
An exhaustive test campaign confirmed the health of the satellite and the solar arrays deployed as planned.
“There were NO out of family readings,” I was told by the Northrop Grumman rep who built ICON.
“No parts had to be replaced.”
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| NASA’s Ionospheric Connection Explorer (ICON) Prelaunch Mission Briefing from Kennedy Space Center in Florida on Oct. 8, 2019. Representatives from NASA, Northrop Grumman Innovation Systems, the Air Force’s 45th Space Wing, and the University of California, Berkeley provided an overview of the ICON mission. ICON will launch on a Northrop Grumman Pegasus XL rocket from the company’s Stargazer L-1011 on Wednesday, October 9, 2019. Credit: Ken Kremer/kenkremer.com/spaceupclose.com |
No further anomalies were detected with Pegasus, said Baez at todays KSC briefing.
As currently planned the ICON satellite mission is expected to launch tomorrow, Wednesday, October 9, 2019 with a 90-minute launch window opening at 9:25 p.m. EDT (0125 GMT). Release from the Stargazer is anticipated for 5 minutes later at 9:30 p.m. EST, said the team.
After LRR approval review the L-1011 Stargazer will fly to a target box about 100 miles off the east coast of Daytona Beach Oct. 9.
“We will fly the airplane in a race track pattern to the drop point,” says Baez. That drop point is about 100 nautical miles east of Daytona.
Given the race track flight pattern the flight team will have two chances to deploy the Pegasus within the 90 minutes launch window if conditions are unfavorable on the first attempt.
Stargazer
then soars aloft and to drop deploy Pegasus at an altitude of about 39,000 feet
(12,000 meters) over the open Atlantic Ocean on an
easterly heading of 105.0 degrees and 27 degree inclination to the equator.
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| NASA ICON Northrop Grumman flight team pose for group shot with ICON ionospheric exploration probe encapsulated inside Northrop Grumman Pegasus XL rocket nestled beneath last flying L-1011 at Cape Canaveral Air Force Station Skid Strip, FL, on Oct. 8, 2019. Launch NET Oct. 9, 2019. Credit: Ken Kremer/kenkremer.com/spaceupclose.com |
The 3-stage solid fueled propulsion Pegasus basically functions as a cruise missile for science for deploying small, lightweight satellites to low Earth orbit (LEO) - in this instance for NASA.
After dropping horizontally for a 5 second free-fall, the first stage of the Pegasus ignites.
The ICON payload will separate and reach orbit about 11 and a half minutes later at an altitude of 380 miles (575 kilometers).
What is the flight profile?
“We fly to 39,000 feet. Drop Pegasus and arm the flight termination system at 2.5 seconds,” Bryan Baldwin, Pegasus Program Manager, Northrup Grumman, told me in a Skid Strip interview last year.
“First stage motor fires after about 5 seconds. It burns for about 88 seconds. Then separate 1st stage motor and ignite 2nd stage. It burns for about the same amount of time - then coasts to proper altitude for ignition of the 3rd stage motor and finalizing orbit. We separate the spacecraft at the designated time. The whole flight takes eleven minutes to spacecraft insertion.”
ICON circles the Earth every 97 minutes.
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| Illustration shows flight profile of NASA ICON Ionospheric Connection Explorer satellite launch by Pegasus XL rocket air-dropped from Northrop Grumman L-1011 carrier jet. Credit: NASA/Northrop Grumman |
Despite
being launched at night, the Pegasus rocket flames will not be visible from the
East Coast, because its so far out and over the horizon.
“You probably can’t see anything from the shore. It’s just too far out. It’s over the horizon due to the curvature of the Earth,” noted Baez.
NASA TV will broadcast the launch live starting at about 9:15 a.m. EDT
Watch NASA TV and the agency’s website
A back up launch opportunity exists on Oct. 10 during the same 90-minute-long window.
The refrigerator-sized ICON weighs 634 pounds (288 kg) and measures 76 inches long and 42 inches wide.
“ICON orbits at an operational altitude of 575 km - and the instruments are all looking down in a horizontal orientation all the time. Except the ion meter which makes measurements at the orbiting altitude,” said Robert Lockwood, Program Director, Science & Environmental Satellites, Northrop Grumman, in an interview with Space UpClose at the Skid Strip last year.
“There is no fuel onboard.”
“It uses regular reaction wheels for standard pointing at LEO.”
ICON is encapsulated inside the Pegasus nose cone. The rocket is 57 feet (17 meters) long, 4.2 meters wing diameter and weighs 52,920 pounds (24,000 kg).
The cylindrically shaped spacecraft is about a meter in diameter. It is powered by a single 5 panel solar array that when deployed extends to the length of a door - 8 1/3 feet long and 2 ¾ feet wide.
ICON will study the ionosphere – “the mixed layer of charged and neutral particles extending from about 50 to 360 miles above Earth’s surface, through which radio communications and GPS signals travel, and the processes there that can distort or even disrupt these signals. Knowledge gleaned from this mission will aid in mitigating its effects on satellites and communications technology worldwide.”
During a baselined 2-year-long mission, ICON will explore the turbulent upper atmospheric ionosphere zone at the interface between the Earth’s terrestrial weather below and space weather above where giant winds whip up the particles – ionized by solar radiation.
The ionosphere is a “dynamic zone high in Earth’s atmosphere can be a source of great beauty such as the aurora, but can also be disruptive to radio communications and satellites and astronaut health. ICON will help determine the physical processes at play in this “frontier of space,” thus paving the way for mitigating their effects on our technology, communications systems and society.”
ICON was built by Northrop Grumman and is based on the LEOStar-2 bus.
The science operations team is led by the University of California, Berkeley. The probe is equipped with a suite four science instruments that will track changes physical and chemical properties of the neutral and charged atmospheric particles; MIGHTI, EUV, FUV and IVM.
“The ICON mission is looking at the interaction of the ionosphere and the charged layer of particles at the top of the atmosphere with space weather,” Lockwood explained.
“It has 4 instruments altogether including two UV instruments [EUV & FUV], an in situ ion velocity meter [IVM] to measure the speed of charged particles, and MIGHTI to measure the speed and temperature of particles in the neutral atmosphere.”
“We know there are effects and correlation with whats happening in the atmosphere and weather. But we don’t really know why.”
“So the science we are doing with ICON is are making measurements to understand how the weather systems effect the profile in the ionosphere.”
Overall this mission marks the 44th launch of Pegasus XL since the maiden flight in 1990.
The last Pegasus launch took place in December 2016 for the launch of NASA’s $157 million CYGNSS hurricane forecasting mission. Space UpClose was on hand – my photos herein.
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| An Orbital ATK L-1011 “Stargazer” aircraft carrying a Pegasus XL rocket with NASA’s CYGNSS spacecraft takes off from the Skid Strip at Cape Canaveral Air Force Station, Florida on Dec. 15, 2016 and successfully launches the spacecraft. Credit: Ken Kremer/kenkremer.com/spaceupclose.com |
The Northrop Grumman team told me they hope to win contract to launch additional Pegasus rockets and have parts for about one and a half rockets in inventory.
ICON is a NASA Explorer class mission managed by NASA’s Goddard Space Flight Center, Greenbelt, MD.
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| NASA ICON Northrop Grumman flight team pose for group shot with ICON ionospheric exploration probe encapsulated inside Northrop Grumman Pegasus XL rocket nestled beneath last flying L-1011 at Cape Canaveral Air Force Station Skid Strip, FL, on Oct. 8, 2019. Launch NET Oct. 9, 2019. Credit: Ken Kremer/kenkremer.com/spaceupclose.com |
Watch for Ken’s continuing
onsite coverage of NASA, SpaceX, ULA, Boeing, Lockheed Martin, Northrop Grumman
and more space and mission reports direct from the Kennedy Space Center, Cape
Canaveral Air Force Station, Florida and Wallops Flight Facility, Virginia.
Stay tuned here for Ken's continuing Earth and Planetary science and human spaceflight news: www.kenkremer.com –www.spaceupclose.com – twitter @ken_kremer – email: ken at kenkremer.com
Dr. Kremer is a research scientist and journalist based in the KSC area, active in outreach and interviewed regularly on TV and radio about space topics.
Stay tuned here for Ken's continuing Earth and Planetary science and human spaceflight news: www.kenkremer.com –www.spaceupclose.com – twitter @ken_kremer – email: ken at kenkremer.com
Dr. Kremer is a research scientist and journalist based in the KSC area, active in outreach and interviewed regularly on TV and radio about space topics.
………….
Ken’s photos are for
sale and he is available for lectures and outreach events
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