NASA Team Troubleshooting Out-of-Contact Spacecraft in CYGNSS Constellation

Since Nov. 26, NASA’s Cyclone Global Navigation Satellite System (CYGNSS) team has not been able to make contact with one of the eight CYGNSS spacecraft, FM06. The team is currently still working to acquire a signal and establish a connection. The other seven spacecraft continue to operate normally and have been collecting science measurements since the FM06 anomaly.

CYGNSS is a constellation of eight small satellites taking measurements of ocean surface winds in and near the eye of the storm throughout the lifecycle of tropical cyclones, typhoons and hurricanes.

If the team isn’t able to reestablish contact, the FM06 satellite would primarily affect the constellation’s spatial coverage.  However, the CYGNSS constellation could continue to meet its scientific requirements and objectives.

CYGNSS was launched Dec. 15, 2016 and completed its prime mission science objectives March 19, 2019. It has been operating in extended mission status since that time.

A Message From CYGNSS Principal Investigator Chris Ruf

We have successfully contacted each of the 8 observatories on our first attempt. This bodes very well for their health and status, which is the next thing we will be carefully checking with the next contacts in the coming days.

It is an amazingly rewarding feeling to spend such an intense and focused time working on CYGNSS and then, in a matter of just a few hours, have the entire constellation suddenly come to life. I am excited (and a little exhausted) and really looking forward to diving into the engineering data in the coming days, and then into the science data in the weeks to follow.



Principal Investigator Dr. Christopher Ruf inspects CYGNSS in the lab, February 2015.
Principal Investigator Dr. Christopher Ruf inspects CYGNSS in the lab, February 2015.

The Winged Pegasus: An Unusual Launch Experience

Technicians and engineers perform final wing installations on the Orbital ATK Pegasus XL rocket which will launch eight NASA Cyclone Global Navigation Satellite System, or CYGNSS, spacecraft.

Pegasus_launch_fullOrbital ATK’s Pegasus rocket gets its payloads into space just like a conventional rocket, but instead of lifting off from the ground, the Pegasus starts its trip already in the air. That’s because a modified L-1011 airliner carries the Pegasus and its payload – CYGNSS in this case – to about 39,000 feet. Pegasus begins its solo flight by being released from the belly of the airliner.

Five seconds of free-fall ends when the solid-fueled first stage ignites. With its main, delta-shaped wing providing lift and a rudder and elevators on the back steering, the Pegasus noses up quickly and heads into orbit, discarding its first stage after leaving the thick portion of the atmosphere. The second and third stages, also burning solid propellants, take over to place the satellites in their prescribed orbit. Here’s a look at what makes the Pegasus flights different:

Forecast Worsens to 40 Percent ‘Go’

A revised forecast from the U.S. Air Force 45th Weather Squadron predicts deteriorating conditions and a 40 percent chance of favorable weather for the launch of NASA’s CYGNSS spacecraft. Launch is scheduled for 8:24 a.m. EST Monday, Dec. 12 aboard an Orbital Sciences ATK air-launched Pegasus XL launch vhicle, seen on the right beneath the L-1011 aircraft called “Stargazer” that will carry the rocket to a deployment altitude about 39,000 feet above the Atlantic Ocean.

The primary concerns are for precipitation, lightning and Cumulus clouds. The rocket is scheduled for deployment over the Atlantic Ocean from Orbital’s L-1011 carrier aircraft, seen above with the Pegasus underneath.

NASA’s Kennedy Space Center will host a Facebook Live event at noon on Saturday from the Skid Strip runway at nearby Cape Canaveral Air Force Station. Briefers will highlight the science involved in the CYGNSS mission, the L-1011 aircraft and the Pegasus rocket, and participants will get a view inside the airplane. The event will stream live on Kennedy’s Facebook page at

Managers from NASA and Orbital ATK will hold a final Launch Readiness Review Saturday morning, followed by two news conferences. The Prelaunch News Conference will be at 1 p.m., followed by the CYGNSS Mission Science Briefing at 1:45 p.m. Both will be carried live on NASA Television and the agency’s website.

CYGNSS will make frequent and accurate measurements of ocean surface winds throughout the lifecycle of tropical storms and hurricanes. The CYGNSS constellation consists of eight microsatellite observatories that will measure surface winds in and near a hurricane’s inner core, including regions beneath the eyewall and intense inner rainbands that previously could not be measured from space. For more information about NASA’s CYGNSS mission, visit