Two Pléiades Neo Earth observation satellites are set to join Airbus’s constellation of high-resolution optical imagers with a launch Tuesday night from French Guiana on the first commercial flight of Europe’s Vega C rocket, a mission delayed from November to change out suspect hardware on the launcher’s payload fairing.
Liftoff is set for 9:47 p.m. EST Tuesday (0147 GMT Wednesday) from the Guiana Space Center in South America, marking the 22nd flight of Europe’s solid-fueled Vega rocket family, and the second in the uprated Vega C configuration.
The 114-foot-tall (34.8-meter) Vega C rocket will propel itself north from the European-run spaceport in French Guiana, heading for a polar orbit with the two Pléiades Neo Earth-imaging satellites for Airbus. The satellites each weigh about a ton at liftoff, and are stacked one on top of the other inside the Vega C’s payload shroud.
The mission Tuesday night, designated VV22, will be the first commercial flight of the new Vega C rocket configuration, following the Vega C’s inaugural test flight July 13 sponsored by the European Space Agency. Arianespace, the Vega rocket’s commercial operator, is in charge of the launch of Airbus’s Pléiades Neo 5 and 6 satellites.
The launch was delayed from Nov. 24 to replace faulty hardware in the pyrotechnic system responsible for jettisoning the Vega C rocket’s payload fairing a few minutes after liftoff. The aerodynamic fairing encloses the Pléiades Neo 5 and 6 satellites during the rocket’s climb through the atmosphere.
The Vega C rocket replaces the old Vega rocket’s solid-fueled first and second stages with wider, heavier motor casings. The third stage motor is unchanged, and the restartable liquid-fueled fourth stage has the same type of engine but carries more propellant. The Vega C’s prime contract, the Italian aerospace company Avio, says the upgraded rocket is capable of hauling up to 5,070 pounds (2.3 metric tons) of payload mass to a 435-mile-high (700-kilometer) polar orbit, an increase over the 3,300-pound (1.5-metric ton) capacity of the basic model of the Vega rocket.
The upgraded Vega C is also taller than the older Vega rocket configuration, and has a larger payload fairing provided by the Swiss company Beyond Gravity, formerly known as RUAG Space.
The higher-performing Vega C can carry two of Airbus’s Pléiades Neo Earth observation satellites on a single mission. The first two satellites in the four-satellite Pléiades Neo constellation launched on separate Vega rockets in 2021.
The Pléiades Neo satellites feature improvements over Airbus’s first-generation Pléiades Earth observation satellites launched in 2011 and 2012. Airbus says it entirely funded the development of the Pléiades Neo satellites, with intentions to sell the imagery commercially to private companies and government users. The company announced the Pléiades Neo program in 2016, and Airbus assembled the Pléiades Neo spacecraft at its facility in Toulouse, France.
The four-satellite program is costing Airbus about 600 million euros, or roughly $700 million.
The Pléiades Neo satellites can produce optical imagery of Earth’s surface with a resolution of 11.8 inches, or 30 centimeters, according to Airbus. That’s good enough to resolve features such as vehicles and road markings. The first two Pléiades satellites launched more than a decade ago have 19.6-inch, or 50-centimeter, resolution.
Airbus has released imagery from the first two Pléiades Neo satellites showcasing their capabilities, picturing lava flows from volcanic eruptions, large-scale music and sports events, and views of aircraft and rockets at airports and spaceports.
The imaging resolution of Airbus’s four Pléiades Neo satellites is comparable to the resolution provided by Maxar’s six-satellite WorldView Legion surveillance satellites due to begin launching next year. The companies are competitors, providing the highest-resolution Earth observation imagery on the global commercial market.
With the help of laser inter-satellite communications links, the Pléiades Neo satellites will be able to respond rapidly to tasking requests within 30 to 40 minutes, according to Airbus.
A single Pléiades Neo satellite, using a new agile pointing capability enabled by control moment gyroscopes, can turn side-to-side to observe the same location every two days. Once all four satellites are in orbit, the constellation will be able to image any location on Earth twice a day.
Each Pléiades Neo spacecraft is designed to operate for at least 10 years. One Pléiades Neo satellite can collect images covering an area of nearly 200,000 square miles (500,000 square kilometers) every day, Airbus says.
“We are just one step away from completing this pioneering constellation, which already covers one million square kilometers per day and delivers images at 30 centimeter native resolution,” said François Lombard, head of intelligence at Airbus Defense and Space. “With this upcoming launch, we will double our capacity and be able to respond to our customers’ needs even faster, providing the best quality in the market for a wide range of military and commercial applications.”
The applications for Pléiades Neo imagery include urban planning and city management, climate change assessments, and determining the impacts of pollution. The satellites can also be tasked to assess the damage from natural disasters.
It will take about 1 hour and 44 minutes for the Vega C rocket to deploy the Pléiades Neo 5 and 6 satellites into a polar, or north-south, orbit about 385 miles (620 kilometers) above Earth.
The first stage of the Vega-C is named the P120C, an enlarged, higher-thrust, longer-burning rocket motor than the P80 first stage flown on the previous version of Vega. The P120C motor, also slated for use as a strap-on booster for Europe’s new Ariane 6 rocket, will fire for about 2 minutes and 26 seconds, generating a million pounds of thrust.
The Vega-C’s second stage, the Zefiro 40, will ignite its solid rocket motor for a two-minute firing. The Zefiro 40 produces about 293,000 pounds of thrust.
The Zefiro 9 third stage motor will ignite will 70,000 pounds of thrust, and will burn out nearly seven minutes after liftoff. The Vega C’s 10.8-foot-wide (3.3-meter) payload fairing, wider than shroud flown on past Vega rockets, will jettison during the third stage burn. The larger fairing allows larger satellites, or more small payloads, to fit into the rocket’s upper compartment.
The Vega C’s upper stage, called the AVUM+, will take over the mission to place the Pléiades Neo 5 and 6 satellites into orbit. The AVUM+ upper stage, with a Ukrainian-made liquid-fueled engine, will fire two times before deploying the Pléiades Neo 5 satellite into orbit about 56 minutes into the mission. Another burn by the upper stage main engine will position the rocket for separation of the Pléiades Neo 6 spacecraft in a slightly different orbit 1 hour and 44 minutes after liftoff.
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