Raumfahrt - Start von Northrop Grummans Pegasus XL rocket mit Ionospheric Connection Explorer (ICON) Satelliten


NASA reschedules long-delayed space science mission



PARIS — A NASA space science mission grounded for nearly two years by problems with its Pegasus rocket is now set to launch in October amid questions about the future of that rocket.

In a statement distributed Sept. 9, NASA said it was now targeting an Oct. 10 launch of the Ionospheric Connection Explorer (ICON) satellite from Cape Canaveral Air Force Station in Florida. The launch vehicle and satellite will be ferried from California to Florida on Northrop Grumman’s L-1011 carrier aircraft Oct. 1.

ICON was originally scheduled to launch in late 2017 from Kwajalein Atoll in the Pacific, a launch that then slipped to June 2018 because of issues with the rocket’s separation system. While en route to Kwajalein for the June 2018 launch, engineers detected “off-nominal” data from the rocket, prompting a return to California.

NASA rescheduled the launch for November 2018, moving the launch to Cape Canaveral because of improved range access. However, after the rocket’s L-1011 aircraft took off for a Nov. 7 launch attempt, engineers again detected off-nominal data from the rocket and scrubbed the launch.

Neither NASA nor Northrop Grumman, the rocket’s manufacturer, have disclosed details on the anomaly, although agency officials said at one meeting that it was linked to the control system for the rocket’s fins. In the new statement, NASA said a joint investigation with Northrop studied “a Pegasus sensor reading that was not within normal limits,” but didn’t discuss what part of the vehicle that sensor was associated with.

“The cause of the issue is understood, and the flight hardware has been modified to address the issue,” NASA said. That includes two captive-carry flights of the Pegasus, attached to its L-1011 aircraft, “to verify the effectiveness of the modification with no issues.”

ICON is a 288-kilogram satellite that will observe the interaction between terrestrial and space weather in the upper atmosphere. Studying that interaction can help scientists better predict the impacts of space weather phenomena that can disrupt radio and navigation transmissions.

The launch is the only Pegasus mission on Northrop Grumman’s manifest for the small rocket, which has flown only infrequently: three times in the last decade, most recently in December 2016. Despite the growing interest in small satellites, the high cost of the Pegasus has prevented it from winning additional business.

The latest sign of Peagsus’ market woes was when NASA awarded a contract in July to SpaceX for a Falcon 9 launch of the Imaging X-Ray Polarimetry Explorer (IXPE) mission even though the satellite, similar in mass to ICON, was baselined to launch on the Pegasus XL. The value of the SpaceX contract, $50.8 million, was less than the $56.4 million for the Pegasus launch of ICON, yet the Falcon 9 has a far greater payload capacity.

Northrop also appears to have lost another customer for Pegasus in Stratolaunch. That venture, funded by the late Paul Allen, planned to use a giant aircraft it developed to launch Pegasus rockets, with the ability to carry three such rockets at a time. That aircraft, though, has not flown since an initial test flight in mid-April and industry sources say Stratolaunch appears to be winding down its operations.

Quelle: SN


Update: 17.09.2019


NASA Opens Accreditation for Launch of Mission to Explore Ionosphere


NASA's Ionospheric Connection Explorer will study the frontier of space: the dynamic zone high in our atmosphere where terrestrial weather from below meets space weather above.


NASA has opened media accreditation for the launch of its Ionospheric Connection Explorer (ICON) mission, targeted to be air-launched over the Atlantic Ocean on a Northrop Grumman Pegasus XL rocket Wednesday, Oct. 9.



Media prelaunch activities will take place at NASA’s Kennedy Space Center and neighboring Canaveral Air Force Station in Florida, with details of the activities to be announced closer to the launch date. Credentialing deadlines are as follows:


  • U.S. media must apply by 4:30 p.m. EDT Friday, Sept. 20.
  • The deadline for international media to apply has passed.


All media accreditation requests should be submitted online at:


For questions about accreditation, please email For other questions, contact Kennedy’s newsroom at 321-867-2468.


ICON and Pegasus will take off aboard the L-1011 Stargazer aircraft from Cape Canaveral Air Force Station for a 90-minute launch window opening at 9:25 p.m. ICON will be launching off the coast of Daytona at 39,000 feet at a heading of 105 degrees.


The ionosphere, where Earth’s weather meets space weather, can be a source of great beauty, but also can be disruptive to radio communications and satellites, and astronaut health. ICON will help determine the physical processes at play in this frontier of space, and help find ways to mitigate their negative effects.

Quelle: NASA


Update: 2.10.2019


Air-launched rocket arrives at Cape Canaveral for satellite delivery mission


File photo of Northrop Grumman’s L-1011 carrier jet and Pegasus XL rocket arriving at the Skid Strip at Cape Canaveral Air Free Station before a previous ICON launch attempt. Credit: NASA/Kim Shiflett

A Northrop Grumman Pegasus XL rocket is back at Cape Canaveral after a cross-country ferry flight Tuesday under an L-1011 carrier jet, ready for final checkouts and a countdown dress rehearsal before an airborne launch off Florida’s east coast Oct. 9 with NASA’s Ionospheric Connection Explorer satellite.

The L-1011 carries jet, named “Stargazer,” touched down at the Skid Strip runway at Cape Canaveral Air Force Station shortly before 5:30 p.m. EDT (2130 GMT) Tuesday after a nearly six-hour flight from Vandenberg Air Force Base, California, where teams readied the Pegasus rocket for flight.

Technicians mated the 634-pound (288-kilogram) ICON spacecraft to the Pegasus XL rocket Sept. 10, then encapsulated the satellite inside the launcher’s payload shroud in a clean room at Vandenberg. Then ground teams transferred the 57-foot-long (17-meter) Pegasus XL rocket to the Vandenberg airfield for attachment underneath the L-1011 carrier plane.

The arrival of the Pegasus rocket at Cape Canaveral begins a week of final inspections, testing and a launch day dress rehearsal.

The L-1011 will take off again from the Skid Strip around 8:30 p.m. EDT on Oct. 9 (0030 GMT on Oct. 10) for an hour-long flight to a predetermined drop box around 100 miles (160 kilometers) east of Daytona Beach.

The flight crew aboard the L-1011 will put the airplane on an easterly heading before commanding the release of the winged Pegasus XL at an altitude of around 39,000 feet (11,900 meters).

The drop time is set for 9:30 p.m. EDT on Oct. 9 (0130 GMT on Oct. 10). There’s a 90-minute launch window available.

Three solid-fueled rocket motors on the Pegasus XL launcher will propel the ICON spacecraft into a 357-mile-high (575-kilometer) orbit.

ICON carries scientific instruments to investigate plasma waves in the ionosphere, a layer in the upper atmosphere where colorful auroras are generated. Changes in the ionosphere can also affect communications and navigation signals coming from satellites, and ICON will study how weather systems lower in the atmosphere can influence conditions at the edge of space.

Like its Pegasus launcher, the ICON spacecraft was built by Northrop Grumman.

ICON’s ride into space has been delayed more than two years by concerns related to its Pegasus rocket.

The mission was originally supposed to launch over the Pacific Ocean near Kwajalein Atoll, the home of a remote U.S. military test site in the Marshall Islands.


NASA’s ICON spacecraft was attached to its Pegasus XL rocket Sept. 10 inside Building 1555 at Vandenberg Air Force Base, California. Credit: NASA/Randy Beaudoin

Engineers wanted more time to inspect the Pegasus rocket motors after they were mishandled during shipment to Vandenberg. That pushed the launch back from June to December 2017, the next availability in the military-run range at Kwajalein.

Then managers decided to ground the mission to assess the reliability of bolt-cutters used to jettison the Pegasus rocket’s payload fairing and separate the satellite in orbit.

NASA and Northrop Grumman tried to launch the $252 million ICON mission twice last year. Both were thwarted by issues related to the solid-fueled rocket’s rudder, which used for aerodynamic stability during the launcher’s first stage burn.

Managers decided to base the launch out of Cape Canaveral, rather than Kwajalein, last summer.

Workers disconnected the ICON spacecraft from the Pegasus rocket late last year and put it in storage while engineers investigated the recurring issues with the launch vehicle.

The satellite was bolted to the rocket again last month as teams readied for a third launch campaign.

'Launch drought' set to end, but weather not looking good for NASA ICON launch

After over a month of waiting, the Space Coast is set to resume having rocket launches once again.

On Wednesday, Northrop Grumman will attempt to air-launch its Pegasus XL rocket that will send NASA's $252 million Ionospheric Connection Explorer science mission, or ICON spacecraft to study the region of near-Earth space, called the ionosphere.

Beginning at 9:25 p.m., ICON and Pegasus will take off aboard Grumman's L-1011 Stargazer aircraft from Cape Canaveral Air Force Station and air-launch the spacecraft over the Atlantic Ocean at 9:30 p.m., according to NASA's press release. The launch window lasts 90 minutes.

A first attempt had been made last November but teams were forced to scrub due to technical issues. Last month, NASA said, "the cause of the issue is understood, and the flight hardware has been modified to address the issue," but did not state what the issue had been. 


Artist rendering of NASA's Ionospheric Connection Explorer, or ICON, in orbit. The spacecraft is targeting an Oct. 6 launch aboard a Northrop Grumman Pegasus XL rocket from Cape Canaveral Air Force Station.

The last time residents were graced with a rocket blasting off from the Cape was at the end of August with United Launch Alliance's Delta IV medium-class rocket. It marked the last time a 'single-stick' version of a Delta IV rocket would ever launch again. 

But even though the brief launch drought is set to end, Wednesday's launch will be different than most. Instead of seeing a vertical rocket take flight from one of the launch pads at the Air Force Station or Kennedy Space Center, Grumman's Pegasus rocket will not launch from the ground, but from the air.

The Stargazer aircraft will release the rocket and the spacecraft about 100 miles off the coast of Daytona Beach where Pegasus will proceed to launch the ICON spacecraft at an altitude of 39,000 feet. That means the only place to view the launch will be on NASA TV. 

Yet as of Monday, weather is currently only 40% "go" for launch. "Primary concerns are cumulus clouds and lightning," according to NASA. 

Having air-launches isn't something new, though. Since 1990, Grumman has been air-launching its Pegasus rockets. The last time one was launched, however, was in December 2016 for NASA's Cyclone Global Navigation Satellite System, or CYGNSS mission. 

For this mission, NASA hopes to understand how the gasses in the ionosphere, "the area through which radio communications and GPS signals travel," affects our own technology and communications systems, according to the space agency. 

The agency will provide live coverage of the launch, available on NASA TV, beginning at 9:15 p.m.

Quelle: Florida Today


Update: 9.10.2019


The Pegasus rocket gallops to space Wednesday night with NASA's ICON spacecraft


On Wednesday evening, NASA is launching a spacecraft from Cape Canaveral Air Force Station called the Ionospheric Connection Explorer which will gather critical data about volatile space weather located in the ionosphere in order to protect astronauts and spacecraft.

The colorful dance of lights in the night sky called aurora borealis, or northern lights, takes place in this mysterious boundary where Earth and space meet. But the beauty of this phenomenon is deceptive.

The ionosphere is loaded with electrically charged gases, solar radiation, and electric and magnetic fields making it very turbulent and unpredictable. These forces can disrupt satellite communication and navigation signals and also damage spacecraft. A sudden space storm can create intense radiation blasts that could be dangerous to astronauts on the International Space Station performing spacewalks.

More: NASA ICON Mission: Things to know about Wednesday's launch

“You don't want to be outside, you want to be protected by the ISS. So it’s important that we can actually predict these things,” director of NASA’s Heliophysics Division, Nicky Fox said.

ICON will study this complex space weather by tracking airglow, a mulit-colored light similar to the auroras that shines from the ionosphere that blankets the Earth. While the auroras are typically confined to extreme northern and southern latitudes, the airglow shines constantly and is much fainter.

Until now it has been difficult to study the ionosphere because it’s hard to observe.  It’s too high for scientific balloons and too low for satellites so NASA worked with Northrop Grumman and the University of California, Berkeley to design a spacecraft perfectly suited for this mission.

“It’s actually up a little bit higher,” Fox said  “so it’s providing information about the top layer of the ionosphere and it’s got all these instruments that look down through all the layers, the red, blue and green airglow looking down through all the different regions of the atmosphere.”


The Northrop Grumman Pegasus XL rocket beneath the company’s L-1011 Stargazer aircraft.
NASA/Ben Smegelsky

ICON weighs in at only 650 pounds and is about the size of a refrigerator. Because of its small size, the ICON spacecraft will launch to space from the Northrop Grumman Pegasus rocket.  But this rocket doesn’t blast off vertically from a launch pad. It is attached to the underbelly of the Stargazer airplane and is carried to 39,000 feet over the open ocean and then released. The Pegasus XL is the only airborne launched rocket in use.

More: 10 great places to watch a launch on the Space Coast

“It doesn’t need a gigantic rocket. This is the perfect size rocket for this kind of mission. We don’t need a Falcon Heavy. We don’t need that much lift capacity,” Fox said.

Unfortunately for Space Coast viewers, this means there isn’t much to see from the ground especially since the plane takes off after sunset.


Part of the flight crew of Northrop Grumman's Stargazer L-1011 aircraft talks about tomorrow's air launch of NASA's ICON (Ionospheric Connection Explorer) satellite aboard a Pegasus XL rocket. (L to R) Mark Kennedy, Pilot/Flight Engineer, Don Walter, pilot, Bob Taylor, Flight Engineer.

The folks with the best view of the launch are actually the pilots flying the Stargazer airplane. When the rocket is dropped the aircraft suddenly loses 52,000 pounds all at once creating a dramatic lift that presses the pilots into their seats.

“It’s like a ride at Disneyland,” Don Walter, one of the pilots of the Stargazer, said. 

After it drops, the pilots get to enjoy a million dollar view as the rocket climbs right past their window.

“You can hear the ignition of the rocket as it accelerates. Sounds like a freight train.”

Don Walter, pilot of Northrop Grumman's Stargazer L-1011 aircraft talks about tomorrow's air launch of NASA's ICON (Ionospheric Connection Explorer) satellite aboard a Pegasus XL rocket.

For those of us on the ground, the best way to experience the launch is to tune into NASA’s livestream, which will be carried on The livestream will include a view of the rocket when it’s released from the plane as well as an infra-camera from the ground.

Quelle: Florida Today


Update: 10.10.2019


NASA, Northrop Grumman Prepare for Launch of ICON


Northrop Grumman’s L-1011 Stargazer aircraft has arrived at the Skid Strip at Cape Canaveral Air Force Station in Florida on Oct. 1, 2019. The company’s Pegasus XL rocket, containing NASA’s Ionospheric Connection Explorer (ICON), is attached beneath the 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

NASA and Northrop Grumman will hold a mission briefing at the agency’s Kennedy Space Center in Florida at 1 p.m. EDT on Tuesday, Oct. 8, in preparation for the launch of NASA’s Ionospheric Connection Explorer (ICON) satellite. Tune in to NASA TV and the agency’s website to watch the mission briefing live.

The Northrop Grumman L-1011 Stargazer aircraft, carrying a Pegasus XL rocket with the agency’s ICON satellite, will take off from the Cape Canaveral Air Force Station Skid Strip on Oct. 9. The launch window will be open from 9:25 to 10:55 p.m., with a targeted release at 9:30 p.m. Ignition of the Pegasus XL rocket will occur five seconds after release from the Stargazer.

ICON is designed to study the frontier of space: the dynamic zone high in our atmosphere where terrestrial weather from below meets space weather above.

Be sure to follow our blog for launch updates. Live launch coverage here and on NASA TV will begin at 9:15 p.m. on Oct. 9.

Due to weather in the area, NASA and Northrop Grumman have decided to move the Pegasus XL and ICON launch 24-hours to October 10 at 9:30 p.m., with takeoff of the Stargazer L-1011 at 8:32 p.m.

NASA’s live broadcast will begin tomorrow at 9:15 p.m. on

The teams are not working any issues.  The rocket, airplane and spacecraft are ready to launch tomorrow.  As always, safety of the crew and mission success are our main focus.

Quelle: NASA


Weather delays NASA ICON mission; next attempt set


On the eve of Northrop Grumman's Pegasus rocket's 44th flight, Don Walter felt confident the launch would go, despite weather conditions at only 30% "go."

"I'm optimistic for tomorrow," the Grumman Stargazer aircraft pilot told reporters on Tuesday at the skid strip at Cape Canaveral Air Force Station. 

But Walter's unwavering certainty could not match the ominous presence of thunderstorms and scattered rain showers approaching the Space Coast Wednesday afternoon, preventing the aircraft from taking flight and sending the rocket into space. 

Once again, Grumman — and NASA — will have to wait another day to attempt to air-launch its Pegasus XL rocket, which will send the space agency's Ionospheric Connection Explorer, or ICON spacecraft to study the region of near-Earth space called the ionosphere. The next opportunity is slated for 9:30 p.m. Thursday.

As if bad news were following them around, a previous attempt to launch this mission had already been made last November, but teams were forced to scrub due to technical issues. Almost a year later, those issues were resolved and the rocket and spacecraft were finally ready to take flight. There was just one problem: weather. 

"Due to weather in the area, NASA and Northrop Grumman have decided to move the Pegasus XL and ICON launch 24-hours," according to NASA's statement. "The teams are not working any issues. The rocket, airplane and spacecraft are ready to launch tomorrow." 

Fortunately, the backup window shows a much brighter outlook. 

For Thursday's launch, weather improves to 70% "go," as calculated by the U.S. Air Force. 

"In the event of a 24-hour delay, drier air begins to move across the peninsula and the potential for precipitation diminishes" according to the 45th Weather Squadron. "Precipitation should be significantly less on Thursday and should be south of the launch area. If there are any concerns on Thursday, it would be from the Cumulus Cloud Rule."

If everything holds, Thursday's launch will be different from most others on the Space Coast. Instead of a vertical rocket taking flight from one of the launch pads at the station or space center, this launch will happen mid-air. 

At approximately 8:32 p.m., Grumman's L-1011 Stargazer aircraft will takeoff from the skid strip with ICON and Pegasus attached. 

Stargazer will fly 39,000 feet over the Atlantic Ocean, about 100 miles off the coast of Daytona Beach, where it will then proceed to release the rocket at 9:30 p.m., launching it into space. 

The only way to view what's going on will be on NASA TV. will carry NASA's feed beginning at 9:15 p.m.

Upon success of the mission, NASA hopes to understand, through ICON, how the ionosphere affects satellite communication and navigation signals, as well as spacecraft and astronauts on the International Space Station performing spacewalks. 

"ICON will help determine the physics of our space environment and pave the way for mitigating its effects on our technology, communications systems and society," according to NASA. 

Quelle: Florida Today


Update: 11.10.2019


ICON Begins Study of Earth’s Ionosphere


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.
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:

Quelle: NASA

















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