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A Cygnus commercial cargo ship containing 3.8 tons of medical and pharmaceutical experiments, technology demonstration equipment, CubeSats, food and supplies drove an Antares rocket into orbit from the east coast of Virginia on Wednesday afternoon, on the first day of a day and a half trip to the international space station.
The 42-meter (42.5-meter) Antares rocket ignited two main engines of the Russian-made kerosene-fueled RD-181 and moved away from launch pad 0A at Wallops Island, Virginia at 4:46 pm 07. EDT (20h46: 07h GMT) Wednesday after a progressive countdown
The two-stage launcher quickly rose from the launch pad overlooking the Atlantic Ocean, releasing four masts in seconds as the first-stage hydraulic steering system engaged to steer the rocket to the southeast, lining up on the flight path of the space station.
The twin-engine first stage generated a full force thrust of 864,000 pounds and was fired for 3 minutes, 35 seconds, before stopping and falling to escape into the Atlantic. After a short climb, the solid-propelled second stage of the Antares rocket ignited to send the supply ship Cygnus into orbit.
Northrop Grumman's telemetry commentator confirmed the separation of the Cygnus spacecraft from 15,940 pounds (7,230 kilograms) about 9 minutes after takeoff, and officials said the launch was successful.
"Nice day, a fantastic launch," said Joel Montalbano, deputy head of NASA's program for the International Space Station. "It's great to have another cargo vehicle en route to the International Space Station."
In one, the Antares rocket carried 63 tiny "ThinSats" built by students as secondary payloads on the second leg. Grouped into groups of three or six, ThinSats are each the size of a slice of bread, containing solar cells to produce energy, data transmitters and sensors to measure parameters such as temperatures and pressures .
Antares' upper stage deployed the ThinSats a few minutes after the release of the Cygnus Space Shuttle – the mission's main payload – from the rocket.
From a standard form factor, children from high school to university integrated sensor and transmitter hardware on the ThinSats with the help of the Virginia Commercial Space Flight Authority, the Twiggs Space Lab, Northrop Grumman and NASA's Wallops Flight Facility.
"My passion in industry and academia is the education of children," said Bob Twiggs, co-inventor of CubeSat and ThinSat. "I'm really excited to be able to do something in space, and if you can excite those kids, man, you have to get out of the way, otherwise they will run over you.
"So, do something like that at a cost that you can get in elementary schools … I think it's really great."
Students from 70 schools in nine states participated in the ThinSats project launched on Wednesday. Officials said they received telemetry signals from 43 ThinSats on Wednesday night, and more data was expected until Thursday night.
The ThinSats launched into an orbit with a perigee, or low point, of 201 km. At this altitude, the aerodynamic drag will quickly make the tiny spaceship fall back into the atmosphere and burn, probably within five or ten days. Rapid disintegration dispels fears that miniature satellites, which may be too small to be accurately tracked by radar, could pose a risk of orbital debris.
A slightly larger spacecraft, called CubeSat, named SASSI ^ 2, separated from the upper stage of the Antares rocket with the ThinSats. SASSI ^ 2 uses instruments from the University of Illinois and Purdue University to measure pressure, heat flux and spectral data as the CubeSat encounters aerodynamic drag in the high atmosphere before burning-entry.
According to Frank DeMauro, vice-president of Northrop Grumman's space division, the Cygnus spacecraft activated its communication, propulsion, guidance and navigation systems shortly after its deployment from the Antares rocket.
The cargo ship made two in-orbit burns shortly after its separation from Antares' second leg, putting the spacecraft on track to arrive at the space station early Friday. The Cygnus has also deployed its two fan-shaped solar panels to start generating energy, DeMauro said at a press conference after the launch.
The craft autonomously performed the two initial orbital lift maneuvers using the shipboard ship's navigation computer, demonstrating a new capability allowing the Cygnus to reach the space station in a little more 36 hours, instead of two or three more classics. days.
"We're going from launches to launches on the ISS in about a day and a half, and one of the things that allows us to get there as quickly is targeted burns at altitude," said DeMauro.
Using GPS satellite position markers and laser telemetry data, the Cygnus tanker will fly autopilot during the final phase of Friday's rendezvous with the space station. The spacecraft is expected to be in a catching position approximately 30 feet (10 meters) below the station by 5.30 am EST (0930 GMT), when astronaut Anne McClain will use the robotic arm built by Canada to seize cargo ship Cygnus, which Northrop Grumman christened "SS Roger Chaffee" in honor of the astronaut who perished with Gus Grissom and Ed White in the fire from Apollo 1 in 1967.
The robotic arm will place the Cygnus on the docking port of the Unity module of the Earth-facing station, where the spacecraft will remain for about three months, allowing astronauts to unload material from its pressurized cabin and replace loading by waste to be eliminated. .
The Cygnus mission launched Wednesday, called NG-11, carries a cargo of 3,536 kg, including new flying robots that can help astronauts perform household chores on the space station, medical experiments and 40 mice to study by astronauts and researchers examine how their immune system copes with the conditions of space flight.
About 6,162 pounds (3,162 kilograms) of food, crew and scientific experiments are in the cargo module of the Cygnus Space Shuttle, built by Thales Alenia Space in Italy, according to NASA's account. The rest of the mission's cargo is mounted outside the spacecraft, where a NanoRacks CubeSat deployer will release three small nanosatellites after the departure of the space station's supply ship.
After being released from the robotic arm of the station in July, the cargo ship will launch into a higher orbit for the deployment of CubeSats, like the maneuvers accomplished by previous Cygnus missions. But instead of ordering the spacecraft to plunge back into the atmosphere for a destructive comeback, Northrop Grumman's ground controllers will oversee months of additional experiments in orbit.
A set of four control moment gyroscopes is installed aboard the Cygnus Space Shuttle for extended mission experience. Using the momentum to manage the pointing or the attitude of the spacecraft, the four rotating gyroscopes will reduce the consumption of liquid propellants of the Cygnus spacecraft, which feed the thrusters normally used to modify the spacecraft. orientation of the supply vessel.
The innovation will allow the Cygnus spacecraft to remain in orbit for up to a year. Cygnus missions did not last more than three or four months.
"We're going to use moment control gyroscopes to control the attitude of the spacecraft, as opposed to the fuel," DeMauro said in an interview with Spaceflight Now before Wednesday's launch.
Northrop Grumman officials have previously said the extended mission demo could last a year, but DeMauro said the duration of the mission will depend on when the engineers achieve all their goals.
"The duration of our mission will really depend on when we reach our goals for the extended mission (demonstration)," DeMauro said.
"We want to do a lot of things," he said. "First of all, we want to show how the spacecraft works with GMAs (gyroscopes with control time) and demonstrate that our platform can use GMAs – not just our platform, but other platforms. Northrop Grumman spacecraft.
"The second thing we want to do is show that avionics can work for a long time," DeMauro said. "We usually run them for several months during tests, then in orbit for three to four months, depending on the length of our presence. This time, we want to demonstrate an even longer period during which the computers are running without error and that the attitude control system is working exactly as intended. "
The control moment gyroscopes were built by Honeywell, using a new miniaturized technology that could be used on future small satellites.
Northrop Grumman wants to keep the NG-11 Cygnus spacecraft in orbit when it launches the company's next replenishment mission to the space station, designated NG-12, currently scheduled for October.
Officials want to offer the future Cygnus spacecraft as a platform for science and technology experiments after leaving the space station. DeMauro stated that the Cygnus space shuttle provided a smooth microgravity environment for orbit research, even better than the space station, disrupted by crew movements and other outside influences. The use of gyroscopes will create more immaculate microgravity conditions, eliminating pulses from thruster fire to alter the orientation of the ship.
"The idea is that, for future missions, we can equip Cygnus for an extended duration, and then, once the main mission is over, propose this extended duration to the government or to commercial entities," he said. DeMauro in an interview with Spaceflight Now. . "We want to give them enough time in orbit, without limitation on the next mission, so it's essential to be able to fly two Cygnus at the same time."
Like previous Cygnus missions, the spacecraft will re-enter the atmosphere and burn over the Pacific Ocean once the long-lasting demonstration is over.
The NG-11 mission is the latest Cygnus flight under Northrop Grumman's first freight contract with NASA. This agreement, signed in 2008, now represents $ 2.89 billion, according to the Government Accountability Office. The company has signed a commercial replenishment service contract, or CRS-2, for at least six other Cygnus missions until 2024, beginning with the NG-12 mission later this year.
"Our goal is to provide NASA with increased scientific capability for every mission," said DeMauro.
For the first time in the NG-11 mission, ground crews at Wallops loaded time-sensitive cargoes into the Cygnus Space Shuttle on the launch pad less than 24 hours before take-off. Northrop Grumman has developed a new mobile payload processing facility, or cleanroom, to be placed over the Antares rocket payload sail after the launcher has been returned to a horizontal position as a result Preliminary checks at launch.
Technicians removed the top of the payload fairing, called "pop-top," and opened the Cygnus hatch to allow teams to load the enclosure containing rodent research experience, as well than that of the bioanalyzer and other elements. The NG-11 mission marked the first time that a rodent research payload was flying aboard a Cygnus tanker, following multiple missions on SpaceX's cargo capsule.
The launch of NG-11 on Wednesday also launched a new navigation system on the Antares rocket, in anticipation of further launcher upgrades planned for the first CRS-2 mission later this year.
Engineers will reinforce the Antares rocket structure during the next mission, to allow the twin-engine first-stage engines, the RD-181, to remain at full throttle while the launcher flies over the most extreme aerodynamic pressure period, or Max-Q, after takeoff. The engines are currently reduced to about 55% of their power to facilitate the passage in Max-Q.
Northrop Grumman also removes some of the unnecessary insulation from the interior of the Castor 30XL's upper stage engine casing and switches from a three-piece fairing adapter to a lighter one-piece structure. Future Antares rockets will also fly with two fewer helium pressurization cylinders in the first leg. Data from previous launches indicated that the rocket did not need additional helium cylinders.
The RD-181 engines will also be launched without heat exchangers, designed to heat the gas to helium in flight. Northrop Grumman officials say the heat exchangers are not being used by the Antares rocket.
The modernization rocket will be known as Antares 230+.
These changes will increase the payload mass that the Antares rocket will put into orbit by approximately 1,763 pounds (800 kilograms), according to Kurt Eberly, vice-president of the Antares program at Northrop Grumman.
"This will allow us to pack even more freight into freight modules," said DeMauro. "We have made some additional changes to be able to pack it more efficiently. This will allow us to have 10% more additional freight in the same volume. "
The Cygnus team has taken a step-by-step approach with upgrades since the spacecraft's inaugural mission.
Since the first missions of the Antares rocket and the Cygnus shuttle in 2013, Northrop Grumman Innovation Systems engineers – formerly Orbital Sciences and Orbital ATK – have introduced a larger cargo module built by Thales and launched new RD-181 engines. for the first stage Antares. Authorities have replaced the Antarès rocket's AJ26 first-stage engines, after one of the engines failed during a launch in 2014, destroying a Cygnus spacecraft heading for the space station and damaging the launch pad from Wallops Island.
DeMauro said the increased performance and increased lifespan of the latest generation of Cygnus tanker ships position the spacecraft for more demanding missions in the future, including deep space flights to support NASA's plans to build a mini-space station called Gateway in lunar orbit with the goal set by the Trump administration of landing astronauts on the moon as early as 2024.
"Entering the publicist space will be a little different," DeMauro said. "So we looked at the avionics upgrades required for the high-radiation environment, different communication systems, docking systems versus docking systems."
Northrop Grumman has signed a contract with NASA to develop a habitat concept based on the Cygnus concept, which could be associated with NASA's gateway around the moon to provide housing for astronauts. Lunar landers could be organized at the bridge for the comings and goings of the moon's surface.
"We believe that we are well positioned to provide NASA with a proven, but improved technology suite on a Cygnus-class vehicle to provide all kinds of services in tight spaces, be they habitat, logistic services, science and utilization services, as well as power and propulsion systems there. Cygnus is a stepping stone from this point of view, "said DeMauro.
"We can even develop this further and be part of the system to put people on the moon itself," DeMauro said.
Grumman Aircraft Engineering Corp., which was purchased by Northrop Corp. in 1994 to form Northrop Grumman, built the Apollo Lunar Landers.
"If you look at this expertise and combine it with our expertise with Cygnus, we know we're going to benefit from it," said DeMauro. "We therefore expect that we play an important role, not only in helping the teams on the moon, but in being able to conceive, build and deliver something that really gets people back on the road. Moon. are so excited about this future. "
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Follow Stephen Clark on Twitter: @ StephenClark1.
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