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(3 September 2020 – ESO) A team of astronomers have identified the first direct evidence that groups of stars can tear apart their planet-forming disc, leaving it warped and with tilted rings.

This new research suggests exotic planets may form in inclined rings in bent discs around multiple stars. The results were made possible thanks to observations with the European Southern Observatory’s Very Large Telescope (ESO’s VLT) and the Atacama Large Millimeter/submillimeter Array (ALMA).

Our Solar System is remarkably flat, with the planets all orbiting in the same plane. But this is not always the case, especially for planet-forming discs around multiple stars, like the object of the new study: GW Orionis. This system, located just over 1300 light-years away in the constellation of Orion, has three stars and a deformed, broken-apart disc surrounding them.

ALMA and the SPHERE instrument on ESO’s Very Large Telescope have imaged GW Orionis, a triple star system with a peculiar inner region. The new observations revealed that this object has a warped planet-forming disc with a misaligned ring. In particular, the SPHERE image (right panel) allowed astronomers to see, for the first time, the shadow that this ring casts on the rest of the disc. This helped them figure out the 3D shape of the ring and the overall disc. The left panel shows an artistic impression of the inner region of the disc, including the ring, which is based on the 3D shape reconstructed by the team. (courtesy: ESO/L. Calçada, Exeter/Kraus et al.)

“Our images reveal an extreme case where the disc is not flat at all, but is warped and has a misaligned ring that has broken away from the disc,” says Stefan Kraus, a professor of astrophysics at the University of Exeter in the UK who led the research published today in the journal Science. The misaligned ring is located in the inner part of the disc, close to the three stars.

The new research also reveals that this inner ring contains 30 Earth-masses of dust, which could be enough to form planets. “Any planets formed within the misaligned ring will orbit the star on highly oblique orbits and we predict that many planets on oblique, wide-separation orbits will be discovered in future planet imaging campaigns, for instance with the ELT,” says team member Alexander Kreplin of the University of Exeter, referring to ESO’s Extremely Large Telescope, which is planned to start operating later this decade. Since more than half the stars in the sky are born with one or more companions, this raises an exciting prospect: there could be an unknown population of exoplanets that orbit their stars on very inclined and distant orbits.

To reach these conclusions, the team observed GW Orionis for over 11 years. Starting in 2008, they used the AMBER and later the GRAVITY instruments on ESO’s VLT Interferometer in Chile, which combines the light from different VLT telescopes, to study the gravitational dance of the three stars in the system and map their orbits. “We found that the three stars do not orbit in the same plane, but their orbits are misaligned with respect to each other and with respect to the disc,” says Alison Young of the Universities of Exeter and Leicester and a member of the team.

They also observed the system with the SPHERE instrument on ESO’s VLT and with ALMA, in which ESO is a partner, and were able to image the inner ring and confirm its misalignment. ESO’s SPHERE also allowed them to see, for the first time, the shadow that this ring casts on the rest of the disc. This helped them figure out the 3D shape of the ring and the overall disc.

The international team, which includes researchers from the UK, Belgium, Chile, France and the US, then combined their exhaustive observations with computer simulations to understand what had happened to the system. For the first time, they were able to clearly link the observed misalignments to the theoretical “disc-tearing effect”, which suggests that the conflicting gravitational pull of stars in different planes can warp and break their discs.

Their simulations showed that the misalignment in the orbits of the three stars could cause the disc around them to break into distinct rings, which is exactly what they see in their observations. The observed shape of the inner ring also matches predictions from numerical simulations on how the disc would tear.

Interestingly, another team who studied the same system using ALMA believe another ingredient is needed to understand the system. “We think that the presence of a planet between these rings is needed to explain why the disc tore apart,” says Jiaqing Bi of the University of Victoria in Canada who led a study of GW Orionis published in The Astrophysical Journal Letters in May this year. His team identified three dust rings in the ALMA observations, with the outermost ring being the largest ever observed in planet-forming discs.

Future observations with ESO’s ELT and other telescopes may help astronomers fully unravel the nature of GW Orionis and reveal young planets forming around its three stars.

Publication

This research was presented in the paper “A triple star system with a misaligned and warped circumstellar disk shaped by disk tearing” to appear in Science (doi: 10.1126/science.aba4633).

About ESO

ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It has 16 Member States: Austria, Belgium, the Czech Republic, Denmark, France, Finland, Germany, Ireland, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile and with Australia as a Strategic Partner. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope and its world-leading Very Large Telescope Interferometer as well as two survey telescopes, VISTA working in the infrared and the visible-light VLT Survey Telescope. Also at Paranal ESO will host and operate the Cherenkov Telescope Array South, the world’s largest and most sensitive gamma-ray observatory. ESO is also a major partner in two facilities on Chajnantor, APEX and ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre Extremely Large Telescope, the ELT, which will become “the world’s biggest eye on the sky”.

About ALMA

The Atacama Large Millimeter/submillimeter Array (ALMA), an international astronomy facility, is a partnership of ESO, the U.S. National Science Foundation (NSF) and the National Institutes of Natural Sciences (NINS) of Japan in cooperation with the Republic of Chile. ALMA is funded by ESO on behalf of its Member States, by NSF in cooperation with the National Research Council of Canada (NRC) and the National Science Council of Taiwan (NSC) and by NINS in cooperation with the Academia Sinica (AS) in Taiwan and the Korea Astronomy and Space Science Institute (KASI). ALMA construction and operations are led by ESO on behalf of its Member States; by the National Radio Astronomy Observatory (NRAO), managed by Associated Universities, Inc. (AUI), on behalf of North America; and by the National Astronomical Observatory of Japan (NAOJ) on behalf of East Asia. The Joint ALMA Observatory (JAO) provides the unified leadership and management of the construction, commissioning and operation of ALMA.

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Globalsat Group successfully tests Iridium Edge Pro

Globalsat Group successfully tests Iridium Edge Pro

(28 October 2020 – Globalsat Group) The Pan-American consortium Globalsat Group, with a multi-country presence throughout the Americas, has been taking part in the successful “beta” tests of the Iridium Edge Pro, the new ultra-compact terminal for Iridium’s SBD service, with on board programmatic capabilities, satellite location signal receiver and various interfaces.

Iridium EDGE Pro Beta Test by Globalsat Group (courtesy: Globalstar Group)

The combination of CANbus and traditional Modbus enhances the flexibility of this satellite IoT device. Iridium partners can also take advantage of the BLE connectivity of Iridium Edge Pro by creating sophisticated solutions which incorporate wireless sensors that collect vital information and deliver it in real time.

By having a built-in GNSS reception module (GPS and other navigation and time systems), it allows resource tracking anywhere in the world, reporting positions and conditions through the Iridium constellation, thus being an extremely easy device to install and link to the resources which need to be monitored or controlled.

Globalsat Group has been able to verify that the multiple functionalities incorporated into this highly adaptive terminal allow it to be part of solutions that will optimize the logistics of operations of any scale, by facilitating very cost-effective and robust and real time data collection, transmission and even decision-making, both autonomous and remote. This can provide huge savings and significant risk reduction for customers, in areas such as:

  • Vessel and fishing monitoring
  • Mission critical electrical component management
  • Long-haul vehicle telematics and fleet management
  • Refrigerated container monitoring
  • Heavy equipment and construction machinery

Marcelo Sturmann, Product Manager of Globalsat Group, commented that “thanks to the opportunity that Iridium offered us, we have managed to understand how the new Iridium Edge Pro device can provide us with new opportunities in markets such as fishing and oil & gas, thanks to the simplicity in its configuration and the characteristics of its interfaces.” Sturmann adds that these qualities “combined with the diversity of resources that the Iridium low orbit constellation offers us and the compatibility with Amazon Web Services through the Iridium CloudConnect service, position Iridium Edge Pro as a product ready to become a success in the M2M and Industrial IoT ecosystem.”

Globalsat Group, in its capacity as a developer of value-added solutions and beta tester of the new device, is testing different applications for several markets, preparing training and live demonstrations for partners and customers in the region.

The consortium, with an extensive presence throughout the Western Hemisphere and the main actor in the MSS (Mobile Satellite Service or Mobile Satellite Service) field in many countries, carries out turnkey projects and also collaborates with other companies which require critical communication systems for sectors such as transport, energy, emergency management, resource monitoring, environment and others. This will facilitate the access of various markets to this technology and the added value necessary for its optimal implementation.

“With Iridium Edge Pro we now have a trio of out-of-the-box asset management products that serve a wide range of customer needs and applications,” said Bryan Hartin, executive vice president of sales and marketing, Iridium. “As a programmable device with features like BLE connectivity, Java programming and CANbus protocol integration, we have created a smarter, more innovative and developer-friendly device than anything in the market today. Add in our truly global coverage with real-time two-way communications, and it’s clear a new standard has been set for the industry.”

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Gilat successfully demonstrates carrying 5G traffic with over Thaicom’s GEO HTS satellite

Gilat successfully demonstrates carrying 5G traffic with over Thaicoms GEO

(29 October 2020 – Gilat) Gilat Satellite Networks announced today that it successfully demonstrated carrying 5G traffic with outstanding performance over Thaicom’s GEO HTS satellite.

With this successful demonstration, Gilat’s cellular backhaul solution is declared operational and ready for implementation in the 5G architecture.

Superior user experience was recorded using Gilat’s Capricorn PLUS VSAT in the live demonstrations last month with two MNOs over Thaicom’s IPSTAR GEO satellite. Using a 5G handset, a large number of applications including: Browsing, Speedtest, Youtube 4K, VoLTE, ViLTE, Virtual Reality, Augmented Reality and even communication with a drone providing a live video stream, were tested with excellent results.

The tests were done with a number of 5G architecture options, including Standalone (SA) and Non-Standalone (NSA), using Gilat’s Capricorn PLUS with adaptation of its patented GTP acceleration, reaching speeds of 400 Mbps download and 100 Mbps upload and at times showing results better than the terrestrial connection.

“We are excited with the results of the close work with our partners in demonstrating the extraordinary capabilities of our flagship VSAT, Capricorn PLUS. We believe that these recorded results of 400/100 Mbps to/from the 5G handset are unique in the industry,” said Alik Shimelmits, Chief Technology and Product Officer at Gilat. “This was successfully demonstrated using Gilat’s Capricorn PLUS over Thaicom’s GEO satellite and MNOs are invited to go ahead and deploy Gilat’s solution for their 5G services.”

“I am very pleased that Thaicom and Gilat have jointly achieved such a significant milestone, further proving the strategic long-term relationship between the companies,” said Abhay Kumar, Regional Vice President Asia Pacific and Japan for Gilat. “This strong partnership went a long way in allowing us to demonstrate these remarkable 5G capabilities and positions us well to deliver value to MNOs as they embark on their journey to deliver differentiated 5G services to the people around the world.”

“Thaicom has deployed Gilat’s multi-service platform across many MNOs over the years. Gilat has been a very strong partner for Thaicom and we highly value this relationship,” said Nile Suwansiri, CCO Thaicom. “This demonstration of 5G capabilities in Thailand will enable us to deliver very strong services with our HTS IPSTAR satellite to address the MNOs satellite-based 5G requirements.”

About Thaicom

Thaicom is a leading Asian satellite operator and end-to-end service provider of satellite enabled communications since 1991. With nearly 30 years of experience in providing cost-effective satellite communications and a presence in 10 countries in Asia-Pacific, Thaicom is a partner of choice for many of the region’s leading broadcasters, telecom operators, and government customers. Thaicom’s video and data platforms offer a portfolio of integrated satellite communications that fuel the demand of these customers to connect and grow their markets in the digital era. Thaicom is a true innovator and satellite industry pioneer: with IPSTAR, Thaicom was the first operator in the world to develop and launch a High Throughput Satellite (HTS). Thaicom currently operates a fleet of four high performance satellites covering Asia, Oceania, and Africa.

About Gilat

Gilat Satellite Networks Ltd. (NASDAQ: GILT, TASE: GILT) is a leading global provider of satellite-based broadband communications. With 30 years of experience, we design and manufacture cutting-edge ground segment equipment, and provide comprehensive solutions and end-to-end services, powered by our innovative technology. Delivering high value competitive solutions, our portfolio comprises of a cloud based VSAT network platform, high-speed modems, high performance on-the-move antennas and high efficiency, high power Solid State Amplifiers (SSPA) and Block Upconverters (BUC).

Gilat’s comprehensive solutions support multiple applications with a full portfolio of products to address key applications including broadband access, cellular backhaul, enterprise, in-flight connectivity, maritime, trains, defense and public safety, all while meeting the most stringent service level requirements. Gilat controlling shareholders are the FIMI Private Equity Funds.

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Impact craters reveal details of Titan’s dynamic surface weathering

Impact craters reveal details of Titans dynamic surface weathering

(29 October 2020 – JPL) Scientists have used data from NASA’s Cassini mission to delve into the impact craters on the surface of Titan, revealing more detail than ever before about how the craters evolve and how weather drives changes on the surface of Saturn’s mammoth moon.

Like Earth, Titan has a thick atmosphere that acts as a protective shield from meteoroids; meanwhile, erosion and other geologic processes efficiently erase craters made by meteoroids that do reach the surface. The result is far fewer impacts and craters than on other moons. Even so, because impacts stir up what lies beneath and expose it, Titan’s impact craters reveal a lot.

This composite image shows an infrared view of Saturn’s moon Titan from NASA’s Cassini spacecraft, captured in 2015. Several places on the image, visible through the moon’s hazy atmosphere, show more detail because those areas were acquired near closest approach. Image Credit: NASA/JPL/University of Arizona/University of Idaho (courtesy: NASA/JPL/University of Arizona/University of Idaho)

The new examination showed that they can be split into two categories: those in the fields of dunes around Titan’s equator and those in the vast plains at midlatitudes (between the equatorial zone and the poles). Their location and their makeup are connected: The craters among the dunes at the equator consist completely of organic material, while craters in the midlatitude plains are a mix of organic materials, water ice, and a small amount of methane-like ice.

From there, scientists took the connections a step further and found that craters actually evolve differently, depending on where they lie on Titan.

Some of the new results reinforce what scientists knew about the craters – that the mixture of organic material and water ice is created by the heat of impact, and those surfaces are then washed by methane rain. But while researchers found that cleaning process happening in the midlatitude plains, they discovered that it’s not happening in the equatorial region; instead, those impact areas are quickly covered by a thin layer of sand sediment.

That means Titan’s atmosphere and weather aren’t just shaping the surface of Titan; they’re also driving a physical process that affects which materials remain exposed at the surface, the authors found.

“The most exciting part of our results is that we found evidence of Titan’s dynamic surface hidden in the craters, which has allowed us to infer one of the most complete stories of Titan’s surface evolution scenario to date,” said Anezina Solomonidou, a research fellow at ESA (European Space Agency) and the lead author of the new study. “Our analysis offers more evidence that Titan remains a dynamic world in the present day.”

Unveiling Secrets

The new work, published recently in Astronomy & Astrophysics, used data from visible and infrared instruments aboard the Cassini spacecraft, which operated between 2004 and 2017 and conducted more than 120 flybys of the Mercury-size moon.

“Locations and latitudes seem to unveil many of Titan’s secrets, showing us that the surface is actively connected with atmospheric processes and possibly with internal ones,” Solomonidou said.

Scientists are eager to learn more about Titan’s potential for astrobiology, which is the study of the origins and evolution of life in the universe. Titan is an ocean world, with a sea of water and ammonia under its crust. And as scientists look for pathways for organic material to travel from the surface to the ocean underneath, impact craters offer a unique window into the subsurface.

The new research also found that one impact site, called Selk Crater, is completely covered with organics and untouched by the rain process that cleans the surface of other craters. Selk is in fact a target of NASA’s Dragonfly mission, set to launch in 2027; the rotorcraft-lander will investigate key astrobiology questions as it searches for biologically important chemistry similar to early Earth before life emerged.

NASA got its first close-up encounter with Titan some 40 years ago, on Nov. 12, 1980, when the agency’s Voyager 1 spacecraft flew by at a range of just 2,500 miles (4,000 kilometers). Voyager images showed a thick, opaque atmosphere, and data revealed that liquid might be present on the surface (it was – in the form of liquid methane and ethane), and indicated that prebiotic chemical reactions might be possible on Titan.

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 moons that have the potential of holding conditions suitable for life.

The Cassini-Huygens mission is a cooperative project of NASA, ESA, 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.

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