Updated at 9:00 pm Eastern
WASHINGTON – A Northrop Grumman Antares rocket successfully launched a Cygnus spacecraft on April 17, carrying nearly three and a half tons of cargo to the International Space Station.
The Antares took off from the mid-Atlantic regional space port at 16:46. After a countdown, Eastern was only affected by a brief problem with the rocket carrier / fitter that was resolved earlier in the afternoon. The Cygnus separated from the upper stage of the Antares rocket nine minutes after take-off in what the controllers called the nominal orbit and deployed its solar panels nearly three hours later.
"The spaceship is very healthy. The performances are very good, "said Frank DeMauro, vice president and general manager of space systems at Northrop Grumman, during a post-launch briefing. After take-off, the spacecraft had two maneuvers called "targeted altitude burns" to climb into its orbit. These burns are a new ability of the Cygnus, he said, which reduce the time needed for the spacecraft to reach the station.
The Cygnus, carrying a cargo of 3,436 kilograms, is to be captured by the robotic arm of the station at approximately 5:30 pm on April 19 to the east. He will stay at the station for about 90 days before being unoccupied, after which he will move to a higher altitude. Orbit and performs an extended mission for at least six months to test its ability to serve as a free flight platform for experiments and technology demonstrations.
1,569 kilograms of this cargo are reserved for scientific investigations. This research includes a rodent experiment to test the effects of spaceflight on the function of antibody production and immune memory, an experiment conducted by a company called FOMS to test the production of high quality fiber optics. microgravity and two robots called Astrobees to maneuver within the station to support research there.
The Astrobees succeed SPHERES, a set of small spherical robots installed on the station for several years for technological demonstrations and educational applications. "SPHERES has been in orbit for over a decade," said Maria Bualat of NASA Ames Research Center at the pre-launch briefing on April 16th. "They are somewhat limited in computing power and are only getting older."
In addition to the Cygnus, the Antares carried 60 "ThinSat" payloads from the upper stage of the rocket several minutes after the Cygnus deployment, as well as one conventional cube. Each ThinSat has the same length and the same width as a unit cube but has only a fraction of its thickness, which allows to fly more in the same volume.
Students from nine state schools built the ThinSats used in educational projects sponsored by the Virginia Commercial Space Flight Authority. ThinSats, deployed in orbits at an altitude of 200 to 250 km, will remain in orbit for about five days before returning. "This will give us a lot of information that is not normally captured," because satellites rarely operate at such a low altitude, said Chris Hale, Virginia Space ThinSat program manager.
Bob Twiggs, co-investor of Cubesat who helped design the ThinSat concept and its curriculum, added that the five-day lifespan has another benefit: "It's the attention span of students. "
This mission, designated NG-11, is the latest in the company's original NASA contract for commercial replenishment (CRS) in 2008. The following missions, starting with the NG-12 this fall, will be executed under the CRS-2 contract. awarded in 2016.
These missions will use an improved version of the rocket called Antares 230+ with several modifications to improve the performance of its payload up to 800 kg, said Kurt Eberly, vice president of Antares at Northrop Grumman. These improvements, including reduced vehicle weight and structural reinforcement, allow the RD-181's engines to maintain 100% thrust throughout the climb.