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Viterbi Engineer to Say Yea or Nea for CO2 Observatory Launch

USC's Ralph Basilio (PhD AE '07) ready to begin a two-year space mission to find Earth's 'missing carbon sinks.'

February 17, 2009 —

Ralph Basilio explains the objectives of the mission at a NASA press briefing held 30 days before launch.

When NASA conducts its final round of ‘go/no goes’ for  launch of the new Orbiting Carbon Observatory (OCO) on February 24, 2009, Viterbi engineer Ralph Basilio (PhD AE ’07) will be the one to decide whether the spacecraft is ready.   

Working on station in the Mission Director’s Center near Launch Complex 576-B at Vandenberg Air Force Base, Basilio is the spacecraft mission director for launch.  Prior to launch, he will be monitoring spacecraft telemetry and weather conditions while coordinating all of the final, 11th-hour details with the launch team in Dulles, VA.   

Basilio is also deputy project manager for the two-year CO2-detection mission, which is designed to measure concentrations of natural and human-induced carbon dioxide around the globe. The goal of the mission is to identify previously unknown places where that greenhouse gas seems to be building up.  The spacecraft will map the entire globe once every 16 days, measuring regions in which CO2 -- the principal driver of global warming -- is being emitted (sources) and absorbed (sinks).   

Ralph Basilio
OCO will thunder into space atop a column of fire, reaching its designated orbit in just 13 minutes.  The launch sequence, said Basilio, is fully automated and controlled by Orbital Sciences Corp. in Dulles, VA.  Once the spacecraft is close to the target point, its four-stage Taurus XL rocket will send a signal to fire bolt cutters and release the payload – a 298-pound, three-channel grating spectrometer about the size of a telephone booth – in a near-polar orbit 438 miles above Earth’s surface.  A minute later, the spacecraft signal will be acquired by NASA’s Tracking and Data Relay Satellite System, and two minutes later, twin solar arrays will begin to unfold like the feathered wings of a giant bird.  Six hours into the mission, OCO’s science instrument will be powered on to begin a series of checkouts and maneuvers that will place it in an operational orbit in NASA’s A-train constellation.

Flying in loose formation with six other Earth-observing satellites – a string of satellites that stretches across 3,800 miles of space – OCO will make the most detailed measurements of atmospheric CO2 ever attempted over ecosystems that have not been adequately measured in the past.  This lack of data makes OCO a critical first step in a longer-range plan to put follow-on CO2 detectors, such as ASCENDS (Active Sensing of Carbon dioxide Emissions over Nights, Days, and Seasons), in space and find out where about 40 percent of the greenhouse gas is going.    
The Orbiting Carbon Observatory will measure places around the world where CO2 is being emitted and absorbed.  (NASA image)

OCO’s place in the A-train will require more flight coordination than is typical, which is where Basilio’s expertise comes in.  At USC, he made spacecraft formation flying the centerpiece of his Ph.D. dissertation, working under the guidance of aerospace and mechanical engineering professor Paul K. Newton, and dissertation committee members Peter Baxendale and Larry Redekopp.

"Ralph was fantastic to work with, very organized, motivated, humble and straight-forward," said Newton, who holds joint appointments in the Viterbi School's Aerospace and Mechanical Engineering Department and the College's Mathematics Department. "He came to me with a dissertation topic to describe mathematically how a coordinated cluster of satellites could move and communicate in some sort of geometric pattern. We worked together on that for several years."

In 2007, Basilio earned a Ph.D. in aerospace engineering, all the while working fulltime at NASA’s Jet Propulsion Laboratory.

At a NASA pre-launch press briefing held 30 days before launch, Basilio described the mission as "the first to provide a complete picture of human and natural sources and sinks of carbon dioxide emissions on regional scales, but everywhere on Earth.”  He also said the checkout phase could take as long as 12 to 13 weeks to complete, because the spacecraft must perform a series of tricky maneuvers in order to assume its proper position in the satellite procession.

“There is obviously more coordination required when operating as one of the seven A-train constellation spacecraft,” Basilio said.  “However, this is a synergistic relationship [with the other satellite teams] and that will make it well worth the effort.”

Basilio will fly to OCO’s Mission Operations Center in Virginia the day after launch to serve as one of the few designated mission operations managers. Orbital Sciences, which manufactured the spacecraft, is also headquarters to in-flight operations.

During the first five and a-half weeks of the mission, the OCO project team will complete the in-orbit checkout phase of the mission, Basilio said.  That phase is divided into three distinct subphases: a 10-day spacecraft checkout subphase, a 20-day orbit ascent subphase, and a seven-day instrument checkout subphase. But until Basilio’s team can verify the health and safety of the spacecraft, no science data will be taken.  

“Somewhere between six and 13 weeks, we’ll be comfortable in saying that the observatory is healthy, it’s now part of the A-train, and it’s time to begin the scientific mission,” he said.