Connect with us

(11 September 2020 – Thales) The Agency for Air Navigation Safety in Africa and Madagascar, ASECNA, has started to broadcast a SBAS (Satellite-Based Augmentation System) signal over Africa & Indian Ocean (AFI) region, providing the first SBAS open service in this part of the world via NIGCOMSAT-1R Satellite managed and operated by Nigerian Communications Satellite under the Federal Ministry of Communications and Digital Economy of Nigeria.

This early open service is provided as part of the “SBAS for Africa & Indian Ocean” programme which pursues the autonomous provision over the continent of SBAS services, to augment the performances of the satellite navigation constellations GPS and Galileo. With improved accuracy to within a meter, and boosted integrity, availability and continuity of safety-related applications, these SBAS services will improve flight safety and efficiency in Africa, and also benefit to the economy in many areas as land, sea and rail transport, as well as mass market applications, supporting user safety, cost-effectiveness and sustainable development.

The launched open service essentially aims to carry-out technical trials, and to undertake with partner airlines field demonstrations for aircraft and rotorcraft, to demonstrate the benefits of the future operational safety-of-life SBAS services, expected from 2024. It will also include early Precise Point Positioning (PPP) and emergency warning service to populations, which performance will be proven through other demonstrations.

The signal-in-space is generated by a dedicated system testbed, developed as part of the “SBAS for Africa and Indian Ocean” preliminary design phase, financed by the European Union and awarded to Thales Alenia Space, Joint Venture between Thales (67%) and Leonardo (33%). The “SBAS for Africa and Indian Ocean” is based on the European EGNOS1 developed by the European Space Agency (ESA) acting under delegation of the European Commission and operated by the European GNSS Agency GSA.

The system prototype uses as reference stations network the SAGAIE network deployed by CNES and ASECNA with the support of Thales Alenia Space.

The signal is broadcasted via the SBAS payload on NigComSat 1R GEO satellite of the Nigerian Communications Satellite Ltd and an uplink station deployed in Abuja (Nigeria). It is compliant to the Standards and Recommended Practices of the International Civil Aviation Organisation, and the Minimum Operational Performance Standard developed by the RTCA (Radio Technical Commission for Aeronautics) organisation. It will be visible in the whole Africa and Indian Ocean, up to the West Australian coast, and also in Europe.

“We are proud to be part of this ambitious program to provide satellite navigation services in the Africa and Indian Ocean region. The use of our geostationary communication satellite NIGCOMSAT-1R navigation payload to broadcast the first signal will be Africa’s premier contribution to SBAS as a regional satellite-based augmentation system for the continent” declared Dr. Abimbola Alale, MD/CEO of NIGCOMSAT Ltd.

“Our longstanding expertise acquired with the development of EGNOS1 SBAS in Europe and KASS SBAS in Korea combined with our new leading-edge satellite positioning technologies makes Thales Alenia Space the ideal partner to best support countries to implement their own SBAS efficiently. The equatorial region represents also a key engineering challenge for such a system due to difficult ionosphere conditions, for which Thales Alenia Space has developed a proven solution”, declared Benoit Broudy, Vice President of the Navigation business at Thales Alenia Space in France.

The provision of the first African SBAS early service is a crucial major step forward in the development of satellite navigation in the AFI Region, and in the deployment of the “SBAS for Africa and Indian Ocean” system, the navigation solution for Africa by Africa. It demonstrates the ambition and commitment of ASECNA to enhance air navigation safety for the benefit of the whole continent, in line with my vision for the unification of the African Sky”, stated Mohamed Moussa, Director General of ASECNA.

About ASECNA

ASECNA is an International public organisation. Its main mission is to provide air navigation services within an airspace of 16,500,000 square kilometers, divided into six flight information regions (F.I.R) as defined by the International Civil Aviation Organization (ICAO). ASECNA also develops solutions for airport management, aviation infrastructure studies and construction, equipment maintenance, calibration of air navigation instruments and training for civil aviation staff. Its 18 Member States are: Benin, Burkina Faso, Cameroon, Central African Republic, Comoros, Congo, Côte d’Ivoire, France, Gabon, Guinea Bissau, Equatorial Guinea, Madagascar, Mali, Mauritania, Niger, Senegal, Chad and Togo.

About Thales Alenia Space

Drawing on over 40 years of experience and a unique combination of skills, expertise and cultures, Thales Alenia Space delivers cost-effective solutions for telecommunications, navigation, Earth observation, environmental management, exploration, science and orbital infrastructures. Governments and private industry alike count on Thales Alenia Space to design satellite-based systems that provide anytime, anywhere connections and positioning, monitor our planet, enhance management of its resources, and explore our Solar System and beyond. Thales Alenia Space sees space as a new horizon, helping to build a better, more sustainable life on Earth. A joint venture between Thales (67%) and Leonardo (33%), Thales Alenia Space also teams up with Telespazio to form the parent companies’ Space Alliance, which offers a complete range of services. Thales Alenia Space posted consolidated revenues of approximately 2.15 billion euros in 2019 and has around 7,700 employees in nine countries.

Source link

0
Continue Reading
Click to comment

Leave a Reply

Your email address will not be published. Required fields are marked *

Space

hints of fresh ice in northern hemisphere

hints of fresh ice in northern hemisphere

(18 September 2020 – JPL) New composite images made from NASA’s Cassini spacecraft are the most detailed global infrared views ever produced of Saturn’s moon Enceladus. And data used to build those images provides strong evidence that the northern hemisphere of the moon has been resurfaced with ice from its interior.

Cassini’s Visible and Infrared Mapping Spectrometer (VIMS) collected light reflected off Saturn, its rings and its ten major icy moons – light that is visible to humans as well as infrared light. VIMS then separated the light into its various wavelengths, information that tells scientists more about the makeup of the material reflecting it.

The VIMS data, combined with detailed images captured by Cassini’s Imaging Science Subsystem, were used to make the new global spectral map of Enceladus.

In these detailed infrared images of Saturn’s icy moon Enceladus, reddish areas indicate fresh ice that has been deposited on the surface. (courtesy: NASA/JPL-Caltech/University of Arizona/LPG/CNRS/University of Nantes/Space Science Institute)

Cassini scientists discovered in 2005 that Enceladus – which looks like a highly reflective, bright white snowball to the naked eye – shoots out enormous plumes of ice grains and vapor from an ocean that lies under the icy crust. The new spectral map shows that infrared signals clearly correlate with that geologic activity, which is easily seen at the south pole. That’s where the so-called “tiger stripe” gashes blast ice and vapor from the interior ocean.

But some of the same infrared features also appear in the northern hemisphere. That tells scientists not only that the northern area is covered with fresh ice but that the same kind of geologic activity – a resurfacing of the landscape – has occurred in both hemispheres. The resurfacing in the north may be due either to icy jets or to a more gradual movement of ice through fractures in the crust, from the subsurface ocean to the surface.

“The infrared shows us that the surface of the south pole is young, which is not a surprise because we knew about the jets that blast icy material there,” said Gabriel Tobie, VIMS scientist with the University of Nantes in France and co-author of the new research published in Icarus.

“Now, thanks to these infrared eyes, you can go back in time and say that one large region in the northern hemisphere appears also young and was probably active not that long ago, in geologic timelines.”

Managed by NASA’s Jet Propulsion Laboratory in Southern California, Cassini was an orbiter that observed Saturn for more than 13 years before exhausting its fuel supply. The mission plunged it into the planet’s atmosphere in September 2017, in part to protect Enceladus, which has the potential of holding conditions suitable for life, with its ocean likely heated and churned by hydrothermal vents like those on Earth’s ocean floors.

The Cassini-Huygens mission is a cooperative project of NASA, ESA (the European Space Agency) and the Italian Space Agency. JPL, a division of Caltech in Pasadena, manages the mission for NASA’s Science Mission Directorate in Washington. JPL designed, developed and assembled the Cassini orbiter.

Source link

0
Continue Reading

Space

Rocket Lab completes final dress rehearsal at Launch Complex 2 ahead of first Electron mission from U.S. soil

Rocket Lab completes final dress rehearsal at Launch Complex 2

(17 September 2020 – Rocket Lab) Rocket Lab has successfully completed a wet dress rehearsal of the Electron vehicle at Rocket Lab Launch Complex 2 (LC-2) at the Mid-Atlantic Regional Spaceport in Wallops Island, Virginia.

With this major milestone complete, the Electron launch vehicle, launch team, and the LC-2 pad systems are now ready for Rocket Lab’s first launch from U.S. soil. The mission is a dedicated launch for the United States Space Force in partnership with the Department of Defense’s Space Test Program and the Space and Missile Systems Center’s Small Launch and Targets Division.

(courtesy: Rocket Lab)

The wet dress rehearsal is a crucial final exercise conducted by the launch team to ensure all systems and procedures are working perfectly ahead of launch day. The Electron launch vehicle was rolled out to the pad, raised vertical and filled with high grade kerosene and liquid oxygen to verify fueling procedures. The launch team then flowed through the integrated countdown to T-0 to carry out the same operations they will undertake on launch day. Before a launch window can be set, NASA is conducting the final development and certification of its Autonomous Flight Termination System (AFTS) software for the mission. This flight will be the first time an AFTS has been has flown from the Mid-Atlantic Regional Spaceport and represents a valuable new capability for the spaceport.

Launch Complex 2 supplements Rocket Lab’s existing site, Launch Complex 1 in New Zealand, from which 14 Electron missions have already launched. The two launch complexes combined can support more than 130 launch opportunities every year to deliver unmatched flexibility for rapid, responsive launch to support a resilient space architecture. Operating two launch complexes in diverse geographic locations provides an unrivalled level of redundancy and assures access to space regardless of disruption to any one launch site.

“Responsive launch is the key to resilience in space and this is what Launch Complex 2 enables,” said Peter Beck, Rocket Lab founder and Chief Executive. “All satellites are vulnerable, be it from accidental or deliberate actions. By operating a proven launch vehicle from two launch sites on opposite sides of the world, Rocket Lab delivers unmatched flexibility and responsiveness for the defense and national security community to quickly replace any disabled satellite. We’re immensely proud to be delivering reliable and flexible launch capability to the U.S. Space Force and the wider defense community as space becomes an increasingly contested domain.”

While the launch team carried out this week’s wet dress rehearsal, construction is nearing completion on the Rocket Lab Integration and Control Facility (ICF) within the Wallops Research Park, adjacent to NASA Wallops Flight Facility Main Base. The ICF houses a launch control center, state-of-the-art payload integration facilities, and a vehicle integration department that enables the processing of multiple Electron vehicles to support multiple launches in rapid succession. The build has been carried out in just a few short months thanks to the tireless support of Virginia Space, Governor Northam, Virginia Secretary of Transportation Shannon Valentine, and Accomack County.

Source link

0
Continue Reading

Space

NASA technology enables precision landing without a pilot

NASA technology enables precision landing without a pilot

(17 September 2020 – NASA) Some of the most interesting places to study in our solar system are found in the most inhospitable environments – but landing on any planetary body is already a risky proposition.

With NASA planning robotic and crewed missions to new locations on the Moon and Mars, avoiding landing on the steep slope of a crater or in a boulder field is critical to helping ensure a safe touch down for surface exploration of other worlds. In order to improve landing safety, NASA is developing and testing a suite of precise landing and hazard-avoidance technologies.

A new suite of lunar landing technologies, called Safe and Precise Landing – Integrated Capabilities Evolution (SPLICE), will enable safer and more accurate lunar landings than ever before. Future Moon missions could use NASA’s advanced SPLICE algorithms and sensors to target landing sites that weren’t possible during the Apollo missions, such as regions with hazardous boulders and nearby shadowed craters. SPLICE technologies could also help land humans on Mars. (courtesy: NASA)

A combination of laser sensors, a camera, a high-speed computer, and sophisticated algorithms will give spacecraft the artificial eyes and analytical capability to find a designated landing area, identify potential hazards, and adjust course to the safest touchdown site. The technologies developed under the Safe and Precise Landing – Integrated Capabilities Evolution (SPLICE) project within the Space Technology Mission Directorate’s Game Changing Development program will eventually make it possible for spacecraft to avoid boulders, craters, and more within landing areas half the size of a football field already targeted as relatively safe.

Three of SPLICE’s four main subsystems will have their first integrated test flight on a Blue Origin New Shepard rocket during an upcoming mission. As the rocket’s booster returns to the ground, after reaching the boundary between Earth’s atmosphere and space, SPLICE’s terrain relative navigation, navigation Doppler lidar, and descent and landing computer will run onboard the booster. Each will operate in the same way they will when approaching the surface of the Moon.

The fourth major SPLICE component, a hazard detection lidar, will be tested in the future via ground and flight tests.

The New Shepard (NS) booster lands after this vehicle’s fifth flight during NS-11 May 2, 2019. (courtesy: Blue Origin)

Following Breadcrumbs

When a site is chosen for exploration, part of the consideration is to ensure enough room for a spacecraft to land. The size of the area, called the landing ellipse, reveals the inexact nature of legacy landing technology. The targeted landing area for Apollo 11 in 1968 was approximately 11 miles by 3 miles, and astronauts piloted the lander. Subsequent robotic missions to Mars were designed for autonomous landings. Viking arrived on the Red Planet 10 years later with a target ellipse of 174 miles by 62 miles.

nasa 3

The Apollo 11 landing ellipse, shown here, was 11 miles by 3 miles. Precision landing technology will reduce landing area drastically, allowing for multiple missions to land in the same region. (courtesy: NASA)

Technology has improved, and subsequent autonomous landing zones decreased in size. In 2012, the Curiosity rover landing ellipse was down to 12 miles by 4 miles.

Being able to pinpoint a landing site will help future missions target areas for new scientific explorations in locations previously deemed too hazardous for an unpiloted landing. It will also enable advanced supply missions to send cargo and supplies to a single location, rather than spread out over miles.

Each planetary body has its own unique conditions. That’s why “SPLICE is designed to integrate with any spacecraft landing on a planet or moon,” said project manager Ron Sostaric. Based at NASA’s Johnson Space Center in Houston, Sostaric explained the project spans multiple centers across the agency.

“What we’re building is a complete descent and landing system that will work for future Artemis missions to the Moon and can be adapted for Mars,” he said. “Our job is to put the individual components together and make sure that it works as a functioning system.”

Atmospheric conditions might vary, but the process of descent and landing is the same. The SPLICE computer is programmed to activate terrain relative navigation several miles above the ground. The onboard camera photographs the surface, taking up to 10 pictures every second. Those are continuously fed into the computer, which is preloaded with satellite images of the landing field and a database of known landmarks.

Algorithms search the real-time imagery for the known features to determine the spacecraft location and navigate the craft safely to its expected landing point. It’s similar to navigating via landmarks, like buildings, rather than street names.

In the same way, terrain relative navigation identifies where the spacecraft is and sends that information to the guidance and control computer, which is responsible for executing the flight path to the surface. The computer will know approximately when the spacecraft should be nearing its target, almost like laying breadcrumbs and then following them to the final destination.

This process continues until approximately four miles above the surface.

nasa 4

NASA’s navigation Doppler lidar instrument is comprised of a chassis, containing electro-optic and electronic components, and an optical head with three telescopes. (courtesy: NASA)

Laser Navigation

Knowing the exact position of a spacecraft is essential for the calculations needed to plan and execute a powered descent to precise landing. Midway through the descent, the computer turns on the navigation Doppler lidar to measure velocity and range measurements that further add to the precise navigation information coming from terrain relative navigation. Lidar (light detection and ranging) works in much the same way as a radar but uses light waves instead of radio waves. Three laser beams, each as narrow as a pencil, are pointed toward the ground. The light from these beams bounces off the surface, reflecting back toward the spacecraft.

The travel time and wavelength of that reflected light are used to calculate how far the craft is from the ground, what direction it’s heading, and how fast it’s moving. These calculations are made 20 times per second for all three laser beams and fed into the guidance computer.

Doppler lidar works successfully on Earth. However, Farzin Amzajerdian, the technology’s co-inventor and principal investigator from NASA’s Langley Research Center in Hampton, Virginia, is responsible for addressing the challenges for use in space.

nasa 5

Langley engineer John Savage inspects a section of the navigation Doppler lidar unit after its manufacture from a block of metal. (courtesy: NASA/David C. Bowman)

“There are still some unknowns about how much signal will come from the surface of the Moon and Mars,” he said. If material on the ground is not very reflective, the signal back to the sensors will be weaker. But Amzajerdian is confident the lidar will outperform radar technology because the laser frequency is orders of magnitude greater than radio waves, which enables far greater precision and more efficient sensing.

The workhorse responsible for managing all of this data is the descent and landing computer. Navigation data from the sensor systems is fed to onboard algorithms, which calculate new pathways for a precise landing.

nasa 6

SPLICE hardware undergoing preparations for a vacuum chamber test. Three of SPLICE’s four main subsystems will have their first integrated test flight on a Blue Origin New Shepard rocket. (courtesy: NASA)

Computer Powerhouse

The descent and landing computer synchronizes the functions and data management of individual SPLICE components. It must also integrate seamlessly with the other systems on any spacecraft. So, this small computing powerhouse keeps the precision landing technologies from overloading the primary flight computer.

The computational needs identified early on made it clear that existing computers were inadequate. NASA’s high-performance spaceflight computing processor would meet the demand but is still several years from completion. An interim solution was needed to get SPLICE ready for its first suborbital rocket flight test with Blue Origin on its New Shepard rocket. Data from the new computer’s performance will help shape its eventual replacement.

John Carson, the technical integration manager for precision landing, explained that “the surrogate computer has very similar processing technology, which is informing both the future high-speed computer design, as well as future descent and landing computer integration efforts.”

Looking forward, test missions like these will help shape safe landing systems for missions by NASA and commercial providers on the surface of the Moon and other solar system bodies.

“Safely and precisely landing on another world still has many challenges,” said Carson. “There’s no commercial technology yet that you can go out and buy for this. Every future surface mission could use this precision landing capability, so NASA’s meeting that need now. And we’re fostering the transfer and use with our industry partners.”

Source link

0
Continue Reading

Trending