https://www.moondaily.com/reports/Queqiao_The_bridge_between_Earth_and_the_far_side_of_the_moon_999.html ----------------------------------------------------------------------------------------------------------------------------------------------------------------- [spacedaily-10] [marsdaily-100] [saturndaily-1] [spacewar-100-] [terradaily-10] [nanodaily-100] [robodaily-100] [radardaily-10] [japan-news-10] ----------------------------------------------------------------------------------------------------------------------------------------------------------------- Moon News ----------------------------------------------------------------------------------------------------------------------------------------------------------------- ----------------------------------------------------------------------------------------------------------------------------------------------------------------- [INS::INS] ----------------------------------------------------------------------------------------------------------------------------------------------------------------- * ------------------------------------------------------------------------------------------------------------------- * 2021 Commercial UAV Expo Americas event, MOON DAILY to be held September 7-9 LIVE in Las Vegas [INS::INS] Queqiao: The bridge between Earth and the far side of the moon by Staff Writers Space & Aerospace Equipment & Services Subscribe to our free Washington DC (SPX) Jun 11, 2021 daily newsletters Simulation of surviving and thriving on [china-lunar-far-side-queqiao-change-4-relay-satellite-lander-hg] the moon based on NASA Artemis Mission for file illustration astronauts living on the moon and Mars Because of a phenomenon called gravitational locking, the Moon always faces the Earth from the same side. This proved useful in the early lunar landing missions in the 20th century, as there was always a direct line of sight for uninterrupted radiocommunications between Earth ground stations and equipment on the Moon. However, gravitational locking makes exploring the hidden face of the moon - the far side - much more challenging, because signals cannot be sent directly across the Moon towards Earth. Still, in January 2019, China's lunar probe Chang'e-4 marked the first time a spacecraft landed on the far side of the Moon. Both the lander and the lunar rover it carried have been gathering and sending back images and data from previously unexplored areas. But how does Chang'e-4 probe communicate with the Earth? The answer is Queqiao, a relay communications satellite, explains Dr. Lihua Zhang from DFH Satellite Co., Ltd., China. As explained by Dr. Zhang in a review paper recently published in Space: Science and Technology, Queqiao is an unprecedented satellite designed specifically for one purpose: to act as a bridge between Chang'e-4 probe and the Earth. Queqiao was launched in 2018 and put into orbit around a point 'behind' the Moon. This point is known as the Earth-Moon Libration point 2, where a special case of gravitational balance allows Queqiao to maintain an orbit such that it has almost constant direct line of sight with both the far side of the Moon and the Earth. Getting the satellite into this peculiar orbit required careful planning and maintenance management, and the success of this operation set a precedent for future attempts at putting satellites in orbit around other Earth-Moon libration points. From its stable place in space, Queqiao helped guide the soft-landing and surface operations of Chang'e-4 probe and has been our intermediary with it ever since. The satellite is equipped with two different kinds of antennas: a parabolic antenna and several spiral antennas. The former, which has a large diameter of 4.2 m, was designed to send and receive signals on the X band (7-8GHz) to and from the rover and lander on the surface of the Moon. Its large size is related the expected noise levels and the low intensity of the transmissions that are sent by surface equipment. On the other hand, the spiral antennas operate on the S band (2-4 GHz) and communicate with Earth ground stations, forwarding commands to the lunar surface equipment and exchanging telemetry and tracking data. Most notably, all these different links can transmit and receive simultaneously, making Queqiao highly versatile. The review paper addresses other important design considerations for Queqiao and future relay satellites, such as the use of regenerative forwarding, the various link data rates involved, and data storage systems for when no Earth ground station is accessible. Over two years of exploration, a great amount of data has been received from the rover and lander through Queqiao. "Scientists in both China and other countries have conducted analysis and research based on the retrieved data, and they have produced valuable scientific results. The longer the operational life of Queqiao, the more scientific outcomes will be achieved," remarks Dr. Zhang. Based on current predictions, Queqiao should be operable on mission orbit for at least five years. Dr. Zhang also addressed the prospects for future lunar missions and how relay communication systems should evolve to support them. Many unexplored areas on the Moon, such as the largest crater at the South Pole, call for multiple relay satellites to maintain constant communication links, which poses an expensive and time-consuming challenge. But what if relay satellites were suitable for more than a single mission? "A sustainable communication and navigation infrastructure should be established to benefit all lunar missions rather than dealing with each mission independently," comments Dr. Zhang, "This infrastructure should adopt an open and extensible architecture and provide flexible, interoperable, cross-supportable, and compatible communications services, which are critical to the success of future lunar explorations." It's likely that future endeavors on the far side of the Moon will be a test on how well we can cooperate to unveil the secrets of our natural satellite. Research Report: "Development and Prospect of Chinese Lunar Relay Communication Satellite" Related Links Lunar Exploration and Space Program Mars News and Information at MarsDaily.com Lunar Dreams and more Tweet Thanks for being here; We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain. With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords. Our news coverage takes time and effort to publish 365 days a year. If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution. SpaceDaily Contributor SpaceDaily Monthly Supporter $5 Billed Once $5 Billed Monthly _ PayPal - The safer, easier way to pay online! * PayPal - The safer, easier way to pay online! * credit card or paypal paypal only [lunar-moon-dust-apollo-astronaut-gene-cer] MOON DAILY Dust: An Out-of-This World Problem Cleveland OH (SPX) Jun 09, 2021 Dust is a nuisance on Earth. Thankfully, we can simply pull out a vacuum or grab a rag to rid ourselves of the concoction of dust mites, fibers, soil, pollen, and other tiny bits. Beyond Earth's atmosphere, dust is insidious. On the Moon, it's made of crushed rock and is damaging to everything from lunar landers to spacesuits and human lungs if inhaled. As NASA readies to return to the Moon with the Artemis program, a team at NASA's Glenn Research Center in Cleveland is working to mitigate dust's ... read more Comment using your Disqus, Facebook, Google or Twitter login. Please enable JavaScript to view the comments powered by Disqus. [INS::INS] ------------------------------------------------------------------------------------------ Share this article via these popular social media networks ------------------------------------------------------------------------------------------ del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle ------------------------------------------------------------------------------------------ MOON DAILY * MOON DAILY ExoMars rover twin begins Earth-based Nano-Bio Materials Consortium introduces new mission in 'Mars Terrain Simulator' AFRL-Industry Co-Development Program A new water treatment technology could also Nanostructured device stops light in its help Mars explorers tracks NASA's Mars helicopter Ingenuity flies for Scientists use DNA technology to build tough 7th time 3D nanomaterials Perseverance Rover Begins Its First Science MOON DAILY Campaign on Mars Scientists identify distinctive deep infrasound rumbles of space launches MOON DAILY Glenn researchers study new, futuristic SpaceX Falcon 9 rocket launches cargo to concept to explore Titan space station Johns Hopkins Scientists Model Saturn's Launch of competition for young people to Interior help make UK spaceflight history Ocean currents predicted on Enceladus SpaceX's night-time launch sends SiriusXM satellite into orbit Hubble Sees Changing Seasons on Saturn MOON DAILY MOON DAILY Manned space mission preps for takeoff First images of Ganymede as Juno sailed by Tianzhou 2 docks with China's new station Leiden astronomers calculate genesis of Oort core module cloud in chronologically order Spacewalks planned for Shenzhou missions NASA's Juno to get a close look at Jupiter's Moon Ganymede China cargo craft docks with space station module Jupiter antenna that came in from the cold MOON DAILY MOON DAILY New spacecraft will use lasers to transmit NASA's new $23 million space commode system video, data in seconds is more than just a toilet New connector for sustainable structures on China accuses US of 'paranoid delusion' over Earth and in space huge innovation bill Radiation-hardened MOSFET qualified for TikToker in space: Virgin Galactic to send commercial and military satellites and space up well-known researcher power solutions Amazon's Jeff Bezos to go to space on Blue SpaceChain to test On-orbit Ethereum Origin rocket Multisignature Transaction Services on ISS [INS::INS] The content herein, unless otherwise known to be public domain, are Copyright 1995-2021 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. General Data Protection Regulation (GDPR) Statement Our advertisers use various cookies and the like to deliver the best ad banner available at one time. All network advertising suppliers have GDPR policies (Legitimate Interest) that conform with EU regulations for data collection. By using our websites you consent to cookie based advertising. If you do not agree with this then you must stop using the websites from May 25, 2018. Privacy Statement. Additional information can be found here at About Us.