European Organisation of Telecommunications by Satellite S.A. (EUTELSAT) is a European satellite operator. Providing coverage over the entire European continent, the Middle East, Africa, Asia and the Americas, it is the world’s third largest satellite operator in terms of revenues. Eutelsat’s satellites are used for broadcasting nearly 7,000 television stations, of which 1,400 are in HD, and 1,100 radio stations to over 274 million cable and satellite homes. They also serve requirements for TV contribution services, corporate networks, mobile communications, Internet backbone connectivity and broadband access for terrestrial, maritime and in-flight applications.
The Mission Extension Vehicle (MEV) is a spacecraft concept proposed by ViviSat. ViviSat was a 50/50 joint venture of aerospace firms U.S. Space and ATK created in 2010 for the purpose of designing, producing and operating the MEV-program. The purpose of the MEV-spacecraft is to operate as a small-scale in-space satellite-refueling spacecraft. Since the original conception of the MEV-program by the ViviSat-company, the Vivisat-venture has been shut down and the company dissolved by ATK (one of the partners in Vivisat) in April of 2016. The MEV-program has continued as a solo-project of ATK. ATK has been since purchased by Northrop Grumman in 2018, and is now Northrop Grumman Innovation Systems. The MEV-program continues under Northrop Grumman.
On schedule to launch in the mid-2020s, NASA’s Wide Field Infrared Survey Telescope (WFIRST) mission will help uncover some of the biggest mysteries in the cosmos. The state-of-the-art telescope on the WFIRST spacecraft will play a significant role in this, providing the largest picture of the universe ever seen with the same depth and precision as the Hubble Space Telescope.
The telescope for WFIRST has successfully passed its preliminary design review, a major milestone for the mission. This means the telescope has met the performance, schedule, and budget requirements to advance to the next stage of development, where the team will finalize its design.
WFIRST is a high-precision survey mission that will advance our understanding of fundamental physics. WFIRST is similar to other space telescopes, like Spitzer and the James Webb Space Telescope, in that it will detect infrared light, which is invisible to human eyes. Earth’s atmosphere absorbs infrared light, which presents challenges for observatories on the ground. WFIRST has the advantage of flying in space, above the atmosphere.
The WFIRST telescope will collect and focus light using a primary mirror that is 2.4 meters in diameter. While it’s the same size as the Hubble Space Telescope’s main mirror, it is only one-fourth the weight, showcasing an impressive improvement in telescope technology.
The mirror gathers light and sends it on to a pair of science instruments. The spacecraft’s giant camera, the Wide Field Instrument (WFI), will enable astronomers to map the presence of mysterious dark matter, which is known only through its gravitational effects on normal matter. The WFI will also help scientists investigate the equally mysterious “dark energy,” which causes the universe’s expansion to accelerate. Whatever its nature, dark energy may hold the key to understanding the fate of the cosmos.
In addition, the WFI will survey our own galaxy to further our understanding of what planets orbit other stars, using the telescope’s ability to sense both smaller planets and more distant planets than any survey before (planets orbiting stars beyond our Sun are called “exoplanets”). This survey will help determine whether our solar system is common, unusual, or nearly unique in the galaxy. The WFI will have the same resolution as Hubble, yet has a field of view that is 100 times greater, combining excellent image quality with the power to conduct large surveys that would take Hubble hundreds of years to complete.
WFIRST’s Coronagraph Instrument (CGI) will directly image exoplanets by blocking out the light of their host stars. To date, astronomers have directly imaged only a small fraction of exoplanets, so WFIRST’s advanced techniques will expand our inventory and enable us to learn more about them. Results from the CGI will provide the first opportunity to observe and characterize exoplanets similar to those in our solar system, located between three and 10 times Earth’s distance from the Sun, or from about midway to Jupiter to about the distance of Saturn in our solar system. Studying the physical properties of exoplanets that are more similar to Earth will take us a step closer to discovering habitable planets.
Video Credit: NASA’s Goddard Space Flight Center/Scott Wiessinger (USRA): Lead Producer/Michael Lentz (USRA): Lead Animator/Claire Andreoli (NASA/GSFC): Lead Public Affairs Officer/Francis Reddy (University of Maryland College Park): Science Writer/Ashley Balzer (GSFC Interns): Writer/Scott Wiessinger (USRA): Narrator/Scott Wiessinger (USRA): Editor
Mini robots that can roll, fly, float and swim, then morph into a single machine? Together they form Shapeshifter, a developing concept for a transformational vehicle to explore treacherous, distant worlds.
In a dusty robotics yard at NASA’s Jet Propulsion Laboratory in Pasadena, California, the Shapeshifter team is testing a 3D-printed prototype of this unusual explorer. A contraption that looks like a drone encased in an elongated hamster wheel rolls across the yard, then splits in half. Once separated, the two halves rise on small propellers, effectively becoming flying drones for aerial exploration. These 3D-printed parts are only the beginning; the team imagines a series of up to 12 robots that could transform into a swimming probe or a team of cave explorers.
Messier 87 (also known as Virgo A or NGC 4486, generally abbreviated to M87) is a supergiant elliptical galaxy in the constellation Virgo. One of the most massive galaxies in the observable universe, it has a large population of globular clusters—about 12,000 compared with the 150–200 orbiting the Milky Way—and a jet of energetic plasma that originates at the core and extends at least 1,500 parsecs (4,900 light-years), traveling at relativistic speed. It is one of the brightest radio sources in the sky and a popular target for both amateur and professional astronomers.
The French astronomer Charles Messier discovered M87 in 1781, and cataloged it as a nebula. M87 is about 16.4 million parsecs (53 million light-years) from Earth and is the second-brightest galaxy within the northern Virgo Cluster, having many satellite galaxies. Unlike a disk-shaped spiral galaxy, M87 has no distinctive dust lanes. Instead, it has an almost featureless, ellipsoidal shape typical of most giant elliptical galaxies, diminishing in luminosity with distance from the center. Forming around one-sixth of its mass, M87’s stars have a nearly spherically symmetric distribution. Their population density decreases with increasing distance from the core. It has an active supermassive black hole at its core, which forms the primary component of an active galactic nucleus. The black hole was imaged using data collected in 2017 by the Event Horizon Telescope, with a final, processed image released on 10 April 2019.
The galaxy is a strong source of multiwavelength radiation, particularly radio waves. Its galactic envelope extends to a radius of about 150 kiloparsecs (490,000 light-years), where it is truncated—possibly by an encounter with another galaxy. Its interstellar medium consists of diffuse gas enriched by elements emitted from evolved stars.
In April, instruments aboard NASA’s Operation IceBridge airborne campaign and the Ice, Cloud and Land Elevation Satellite-2 succeeded in measuring the same Arctic sea ice at the same time, a tricky feat given the shifting sea ice. Scientists have now analyzed airborne and spaceborne height measurements, and found that the two datasets match almost exactly, demonstrating how precisely ICESat-2 can measure the heights of the sea ice’s bumpy, cracked surface.
When a new NASA space telescope opens its eyes in the mid 2020s, it will peer at the universe through some of the most sophisticated sunglasses ever designed. This multi-layered technology, the coronagraph instrument, might more rightly be called “starglasses”: a system of masks, prisms, detectors and even self-flexing mirrors built to block out the glare from distant stars — and reveal the planets in orbit around them. Normally, that glare is overwhelming, blotting out any chance of seeing orbiting planets. The star’s photons — particles of light — swamp those from the planet when they hit the telescope.
WFIRST’s coronagraph just completed a major milestone: a preliminary design review by NASA. The instrument has met all design, schedule and budget requirements, and can now proceed to the next phase, b uilding hardware for flight. The WFIRST mission’s coronagraph is meant to demonstrate the power of increasingly advanced technology. As it captures light directly from large, gaseous exoplanets, and from disks of dust and gas surrounding other stars, it will point the way to the future: single pixel “images” of rocky planets the size of Earth. Then the light can be spread into a rainbow spectrum, revealing which gases are present in the planet’s atmosphere — perhaps oxygen, methane, carbon dioxide, and maybe even signs of life.
The two flexible mirrors inside the coronagraph are key components. As light that has traveled tens of light-years from an exoplanet enters the telescope, thousands of actuators move like pistons, changing the shape of the mirrors in real time. The flexing of these “deformable mirrors” compensates for tiny flaws and changes in the telescope’s optics. Changes on the mirrors’ surfaces are so precise they can compensate for errors smalle r than the width of a strand of DNA. These mirrors, in tandem with high-tech “masks,” another major advance, squelch the star’s diffraction as well – the bending of light waves around the edges of light-blocking elements inside the coronagraph.
The result: blinding starlight is sharply dimmed, and faintly glowing, previously hidden planets appear. The star-dimming technology also could bring the clearest-ever images of distant star systems’ formative years — when they are still swaddled in disks of dust and gas as infant planets take shape inside.
The instrument’s deformable mirrors and other advanced technology — known as “active wavefront control” — should mean a leap of 100 to 1,000 times the capability of previous coronagraphs.
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