Subscriber CaaC (John)+ Posted December 5, 2019 Author Subscriber Posted December 5, 2019 US meteorite adds to origins mystery In January 2018, a falling meteorite created a bright fireball that arced over the outskirts of Detroit, Michigan, followed by loud sonic booms. The visitor not only dropped a slew of meteorites over the snow-covered ground, but it also provided information about its extra-terrestrial source. Although tens of thousands of meteorites have been recovered by humans, scientists have only been able to trace the orbits of a small number. Most of these have been calculated in the last decade. Scientists can use information about how the meteorite burned through Earth's atmosphere to calculate how the rocky object moved through space before it transformed into a fireball. Researchers cannot trace the specific path of an object back through time - there are too many variables that could have affected its motion. But they can determine the most likely paths. Studying the likely orbits of similar asteroids can help to reveal their parent body, the larger asteroid they once were part of. Video of the fireball over Michigan: "This is a great way to do what amounts to a low-cost asteroid sample return mission," says Dr Peter Brown, who studies asteroids at Canada's University of Western Ontario. "In this case, the sample comes to us. We don't have to go to the sample." Dr Brown and his colleagues gathered information from fireball surveys as well as videos posted on social media to reconstruct a potential orbit for the Hamburg meteorite, named after the small Detroit suburb it buzzed. The team then worked with several of the amateur photographers to calibrate their observations. "We spent a lot of time scouring YouTube and Twitter," he says. The researchers found that the Hamburg meteorite was a fairly typical fireball. It likely entered the atmosphere with a mass ranging from 60kg to 220kg and a diameter between 3m and 5m. Travelling at about 16 km/s, it produced two major flares at 24.1km and 21.7km above the ground. The total energy produced by the fireball equalled somewhere between two and seven tonnes of TNT. Metal meteorite quest set to get underway The US detects huge meteor explosion UK meteorite hunt bags large haul A growing trend While some researchers took to the ground to hunt for dark meteorites in the Michigan snow, Dr Brown and his colleagues took to the internet to find reports of the fall. Because the region was densely populated, Dr Brown said there were a lot of video recordings that captured the fall. Out of the wealth of camera phone and security footage, they tracked down almost 30 unique videos that were sharp enough to reveal their location. Of these, only a handful was good enough for the team members to perform detailed calibration. How do you calibrate a casual fireball video? First, you need to have a positional reference that helps to pinpoint where the video was taken from. Ideally, the same camera would be placed in the exact spot where the meteorite fall was originally viewed - though often a similar camera was used instead. Measurements from those videos revealed the angle that the incoming meteorite was travelling on. "A lot of the legwork was just talking to people," Dr Brown says. In addition to the casual imagery, the researchers looked at images from fireball surveys, where the calibration had already been performed. While the official data was easier to work with, Dr Brown says that smartphones and dashboard cameras often tend to have higher resolution, providing better precision data if they can be calibrated. The growing prevalence of these kinds of cameras "has almost revolutionised this area," he says. While humans have collected meteorites for thousands of years, it wasn't until 1959 that the first meteorite orbit was recovered. Cameras operated by the Ondrejov Observatory in the Czech Republic recorded the fall of the Pribram meteorite, allowing the researchers to trace its orbit back to the asteroid belt. For the first time, astronomers were confident that meteors came from asteroids. "That orbit really sort of sealed it," Dr Brown says. Fireball networks came online through the 1960s, 70s, and 80s, and by 2000, four meteorite orbits were known. Three of those were H-chondrites, the iron-rich class of meteorites that most commonly falls, and the group that Hamburg belongs to. Since 2000, those meteorites with orbits that can be calculated have increased. Another 10 were spotted by 2010. The last few years have produced a handful of traceable meteorites annually, Dr Brown says. Today, there are about 30 meteorites whose orbits have been calculated. While the spread of cameras dedicated to tracking fireballs has played an important role, Dr Brown says that casual recordings have also advanced the field. The Hamburg fall "was very well recorded, and that's what makes it so interesting", Dr Brown says. After the more powerful 2013 Chelyabinsk fireball, "there's no other fall that had so many video records". But casual video recordings have their downfall. Because they are so much more difficult to calibrate than official surveys, they take more time. That can move them down the priority list for swamped scientists. Dr Brown knows of researchers working on nearly 10 more meteorite orbits, but he estimates that others exist. "There are data for probably another 20 that people just haven't tried to do because it's so much work," he says. "It's a difficult process." More questions than answers Although H-chondrites make up the bulk of the meteorites that survive the plunge through Earth's atmosphere, their origin remains a mystery. In 1998, astronomers proposed the large main-belt asteroid (6) Hebe as the primary parent body because it resembled H-chondrites. Hebe's orbit sits in a location where Jupiter's gravitational forces can stir up material, allowing it to escape from the asteroid belt. Near-Earth asteroids similar to Hebe have also been spotted, suggesting that something - probably the giant planet Jupiter - slung material from the asteroid belt. However, other main-belt asteroids similar to H-chondrites have been identified in recent years, muddying the picture. Of the 30 or so meteorites with known orbits, nearly half are H-chondrites. So far, however, those objects don't seem to be coming from the outer asteroid belt - the side facing Jupiter - where Hebe orbits. Instead, they appear to start their journey from the middle and inner belt, closer to the Sun. And the new discovery isn't helping. "Hamburg, unfortunately, adds more questions about the orbit of H-chondrites than it answers," Dr Brown says. Narrowing things down will take more meteorite samples. Dr Brown estimates that doubling the existing known orbits for H-chondrites will allow researchers to make more solid associations with a parent body. That assumes the iron-rich asteroids come from a single source; it's possible they come from two or more locations in the asteroid belt. "It's a very complicated story," Dr Brown says. "We need to get more of these if we're going to answer these questions more fully." https://www.bbc.co.uk/news/science-environment-50419924 Quote
Subscriber CaaC (John)+ Posted December 20, 2019 Author Subscriber Posted December 20, 2019 We're likely to find alien life in the next decade, scientists say. Here's where NASA plans to look — in our solar system and beyond. SLIDES - 1/22 Many NASA scientists think we're on the verge of finding alien life. That's because the agency plans to dramatically ramp up its search for signs of extraterrestrial life in the next 10 years - in ancient Martian rock, hidden oceans on moons of Jupiter and Saturn, and the atmospheres of faraway planets orbiting other stars. "With all of this activity related to the search for life, in so many different areas, we are on the verge of one of the most profound discoveries ever," Thomas Zurbuchen, NASA's former administrator, told Congress in 2017. Ellen Stofan, NASA's former chief scientist, said in 2015 that she believes we'll get "strong indications of life beyond Earth in the next decade and definitive evidence in the next 10 to 20 years." "We know where to look, we know how to look, and in most cases, we have the technology," she added, according to the LA Times. Here's how NASA plans to track down alien life - in our solar system and beyond. (SLIDES above). https://www.msn.com/en-gb/news/photos/were-likely-to-find-alien-life-in-the-next-decade-scientists-say-heres-where-nasa-plans-to-look-%e2%80%94-in-our-solar-system-and-beyond/ss-BBYaOzQ?li=BBoPWjQ#image=1 Quote
nudge Posted December 23, 2019 Posted December 23, 2019 A year in space exploration: https://interestingengineering.com/12-of-the-most-exciting-space-moments-of-2019 1 Quote
Subscriber CaaC (John)+ Posted December 28, 2019 Author Subscriber Posted December 28, 2019 Satellite constellations: Astronomers warn of threat to the view of the Universe Astronomers are warning that their view of the Universe could be under threat. From next week, a campaign to launch thousands of new satellites will begin in earnest, offering high-speed internet access from space. But the first fleets of these spacecraft, which have already been sent into orbit by US company SpaceX, are affecting images of the night sky. They are appearing as bright white streaks, so dazzling that they are competing with the stars. Scientists are worried that future "mega-constellations" of satellites could obscure images from optical telescopes and interfere with radio astronomy observations. Dr Dave Clements, an astrophysicist from Imperial College London, told BBC News: "The night sky is a commons - and what we have here is a tragedy of the commons." The companies involved said they were working with astronomers to minimise the impact of the satellites. Why are so many satellites being launched? It's all about high-speed internet access. Instead of being constrained by wires and cables, satellites can beam internet access down to the ground from space. And if you have lots of them in orbit, it means even the most remote regions can get connectivity. To give you an idea of the numbers, there are currently just 2,200 active satellites flying around the Earth. But as of next week, the Starlink constellation - a project by US company SpaceX - will start sending batches of 60 satellites into orbit every few weeks. This will mean about 1,500 satellites have been launched by the end of next year, and by the mid-2020s there could be a fleet of 12,000. UK company OneWeb are aiming for about 650 satellites - but this could rise to 2,000 if there is enough customer demand. While Amazon has a constellation of 3,200 spacecraft planned. Why are astronomers worried? In May and November, Starlink sent 120 satellites into orbits below 500km. But stargazers were concerned when the spacecraft appeared as bright white flashes on their images. Dhara Patel, an astronomer at the Royal Observatory Greenwich said: "These satellites are about the size of a table, but they're very reflective, and their panels reflect lots of the Sun's light, which means that we can see them in images that we take with telescopes. "These satellites are also big radiowave users… and that means they can interfere with the signals that astronomers using. So it also affects radio astronomy as well." She warns that the problem will grow as the numbers of satellites in orbit increase. What could this mean for research? Dr Clements believes the satellites could have a real impact on observations. "They present a foreground between what we're observing from the Earth and the rest of the Universe. So they get in the way of everything. "And you'll miss whatever is behind them, whether that's a nearby potentially hazardous asteroid or the most distant Quasar in the Universe." He said it would be particularly troublesome for telescopes taking large surveys of the sky, such as the future Large Synoptic Survey Telescope (LSST) in Chile. He explained: "What we want to do with LSST and other telescopes is to make a real-time motion picture of how the sky is changing... "Now we have these satellites that interrupt observations, and it's like someone's walking around firing a flashbulb every now and again." But Prof Martin Barstow, an astrophysicist from the University of Leicester said some of the problems could be fixed. "The numbers of satellites do sound frightening, but actually space is big - so when you superimpose them all on the sky, the density of these things is not going to be very large," he said. "And because the satellites have known positions, you can mitigate. A satellite is going to be a dot in an image and it might appear as a transient burst of light - but you will know about it and can remove it from the image. "It will cost effort and work for observatories to deal with it, but it can be done." For radioastronomy, however, the constellations could pose more of an issue - especially for relatively new telescopes, such as the Square Kilometre Array (SKA). The radio signals the satellites use will be different from the ones astronomers are looking for, but they could still interfere, said Prof Barstow. What do the companies involved say? SpaceX told the BBC that they were actively working with international astronomers to minimise the impact of the Starlink satellites. For their next launch, they are trialling a special coating that is designed to make the spacecraft less bright to see if this will help. OneWeb said they wanted to be a "thought leader in responsible space" and were putting their satellites into an orbit of 1,200km so they would not interfere with astronomical observations. Ruth Pritchard-Kelly, vice president of OneWeb, said: "We chose an orbit as part of our dedication to the responsible use of outer space… And we've also talked to the astronomy community before we launched to make sure that our satellites won't be too reflective and that there won't be radio interference with their radio astronomy." She added that it shouldn't be a case of having to choose between connectivity and astronomy. "There is no question that the entire world is entitled to be connected to the internet…. So it's going to happen. And probably three or four of these systems are going to happen," she said. "And the question will be working with the other stakeholders to make sure that we're not interfering with them, whether they are existing satellite technologies, or the mobile phone on the ground, or the astronomy community. "We know we're going to work it out with everybody." Stargazers will be watching the skies to see if a compromise can be found. https://www.bbc.co.uk/news/science-environment-50870117 Quote
Subscriber CaaC (John)+ Posted December 28, 2019 Author Subscriber Posted December 28, 2019 2020 celestial events to look forward to SLIDES - 1/28 Quote
Subscriber CaaC (John)+ Posted January 6, 2020 Author Subscriber Posted January 6, 2020 The telescope that looks further back in time A team of astronomers and engineers in Edinburgh have constructed an instrument that can look further back in time than ever before. It is a key part of an international mission to launch a huge new telescope a million miles from Earth. The James Webb Space Telescope (JWST) is years behind schedule and billions of dollars over budget. But scientists say it will have the ability to detect any galaxy in the universe. James Webb Space Telescope comes together Launch of Hubble's successor pushed back to 2021 Could Nasa's James Webb Space Telescope detect alien life? How can you look back in time? The telescope will be fitted with a Mid Infrared Instrument (MIRI), which is one of four key detectors. MIRI will be able to look back in time to just a few hundred million years after the Big Bang - thought to have happened more than 13.5 billion years ago. Speed of light This ability to look back in time is based on the fact that even light has a speed limit. It bowls along at 186,000 miles per second. That means that the natural light reaching us now left the sun more than eight minutes ago. However, the larger the distance that you observe in the universe, the more time has passed since the light you are observing set off on its journey towards you. So if you look at a star that is 30 light-years away, that is what it looked like 30 years ago. The same applies to stars that are millions of light-years away. The telescope is perfect for studying those worlds and distant planets that orbit other suns - known as exo-planets because they exist outside our solar system. The existence of the first exoplanet was confirmed in 1995. Now we know of more than 4,000 of them. MIRI will allow astronomers to look at them in greater detail, including looking through their atmospheres for tantalising signs of extra-terrestrial life. How does it work? Like all space telescopes, the JWST starts with an advantage over its earthbound counterparts. There is no atmosphere to distort our view of the stars, so stars do not twinkle in space. All of the JWST's instruments will observe infrared light. One advantage of that is that infrared can pass through the interstellar dust that blocks visible light. Another reason is that visible light travelling from a faraway star is stretched on its way to us. Its wavelength gets longer, meaning light that was in the range we humans can see has shifted down the spectrum into the infrared. The effect is called redshift and means that if you want to look further back in time, you must look at things which appear invisible to us. However, these "invisible" objects are not invisible to the James Webb telescope. Three of its detectors are tuned to the near-infrared. As the term suggests, that is just beyond the reds we can see. But MIRI can look deeper, into the mid-infrared. So further away and long ago. Prof Alistair Glasse is the lead scientist on MIRI and explained how the detector works. "It can see the colours of objects, for example, that are approximately at room temperature," he said. "That makes it particularly interesting if you want to study planets orbiting other stars." And there is more because MIRI will be able to look back almost to the dawn of the universe. MIRI's European Principal Investigator Prof Gillian Wright said: "We think that the first stars that formed were very big and they started the chain of making the elements and the stars we see around us. "We don't know very much about [this era]. We know what the structure of the universe looked like shortly after the Big Bang, and we know from Hubble and the other missions what the galaxies look like now or in later epochs. "But the little piece in the middle? How did the first ones form? We don't know very much about that era." A mirror larger than Hubble's The JWST involves NASA, European Space Agency (ESA) and the Canadian Space Agency. It is a huge undertaking - literally. The telescope's 6.5m mirror is several times larger than that of Hubble's. In its working configuration it is too big for any rocket, so must be unfolded in space. So too the JWST's huge sun shield, designed to keep its working temperature just a few degrees above absolute zero. It is made of five delicate layers as thin as cling film, which will have to be stretched into place. The JWST is being exhaustively tested here on Earth because it is going where no-one can fix it. It will orbit L2, a point in space where the gravitational pull of the Sun and Earth are in balance - roughly a million miles away from here. The mission, scheduled for 2021, is planned to last less than six years. https://www.bbc.co.uk/news/uk-scotland-edinburgh-east-fife-50984467 Quote
Subscriber CaaC (John)+ Posted January 8, 2020 Author Subscriber Posted January 8, 2020 Vast 'star nursery' region found in our galaxy Astronomers have discovered a vast structure in our galaxy, made up of many interconnected "nurseries" where stars are born. The long, thin filament of gas is a whopping 9,000 light-years long and 400 light-years wide. It lies around 500 light-years from our Sun, which is relatively close by in astronomical distances. The discovery, outlined in the journal Nature, came from work to assemble a new map of the Milky Way. An international team analysed data from the European Gaia space telescope, which was launched in 2013. The monolithic structure has been dubbed the Radcliffe Wave, in honour of Harvard University's Radcliffe Institute for Advanced Study in Cambridge, Massachusetts. "What we've observed is the largest coherent gas structure we know of in the galaxy, organized not in a ring but in a massive, undulating filament," said co-author Joao Alves, from the University of Vienna, Austria, and Harvard. It is in the spiral arm (the long thin extensions of spiral galaxies that give them their name) located closest to our Solar System. Gaia was launched with the intention of precisely measuring the position, distance and motion of stars in our galaxy. Team members used data from the European Space Agency telescope, along with other measurements, to construct a detailed, 3D map of interstellar matter in the Milky Way. The results correct a previous view of this region of the Milky Way. Many of the star-forming regions found in the Radcliffe Wave were previously thought to be part of a structure called Gould's Belt that was around 3,000 light-years (20 quadrillion km) wide. Small, or far away? First described in 1879, Gould's Belt was thought to be comprised of star-forming regions, believed to be oriented around the Sun in a ring. The new study in Nature transforms that picture into one of a 90 quadrillion-kilometre-long, four quadrillion-kilometre-wide star-forming filament. Co-author Prof Alyssa Goodman, from Harvard, commented: "We were completely shocked when we first realised how long and straight the Radcliffe Wave is, looking down on it from above in 3D." She added: "The wave's very existence is forcing us to rethink our understanding of the Milky Way's 3D structure." All of the stars in the Universe, including our Sun, are formed when clouds of gas and dust undergo a gravitational collapse. But working out how much mass the clouds have and how large they are has been difficult because these things depend on how far away the clouds are. Co-author Douglas Finkbeiner said: "Studying stellar births is complicated by imperfect data. We risk getting the details wrong because if you're confused about distance, you're confused about size." The results are being presented at the 235th meeting of the American Astronomical Society in Honolulu, Hawaii. https://www.bbc.co.uk/news/science-environment-51021704 Quote
Subscriber CaaC (John)+ Posted January 19, 2020 Author Subscriber Posted January 19, 2020 (edited) SpaceX to practise emergency crew capsule escape America aims to take another step on Sunday towards being able to send its own astronauts into orbit again. California's SpaceX company will practise what to do in the event that one of its rockets carrying a human crew fails shortly after lift-off. If the test is completed successfully, it should clear the way for regular astronaut launches later this year. The US has not launched from its own soil since the retirement of the space shuttles nine years ago. It has been riding the Russian Soyuz system instead. The US space agency (Nasa) has contracted both SpaceX and the aerospace giant Boeing to come up with home-grown alternatives. SpaceX - with its Falcon rocket and Dragon capsule - is now in the final stages of development. Sunday's in-flight abort manoeuvre is really the last major obstacle the firm faces before receiving the full certification it needs to begin operational astronaut taxi services. (The test was due to take place on Saturday but is delayed to Sunday because of weather concerns.) FULL REPORT Edited January 19, 2020 by CaaC (John) 1 Quote
nudge Posted January 19, 2020 Posted January 19, 2020 The in-flight test Crew Dragon's launch escape capabilities was successful! 1 Quote
Subscriber CaaC (John)+ Posted January 22, 2020 Author Subscriber Posted January 22, 2020 A space mission to reveal 'truths' about climate change The UK is going to lead a space mission to get an absolute measurement of the light reflected off Earth's surface. The information will be used to calibrate the observations of other satellites, allowing their data to be compared more easily. Called Truths, the new spacecraft was approved for development by European Space Agency member states in November. Proponents of the mission expect its data to help reduce the uncertainty in projections of future climate change. Scientists and engineers met on Tuesday to begin planning the project. Industry representatives from Britain, Switzerland, Greece, the Czech Republic and Romania gathered at Esa's technical centre in Harwell, Oxfordshire. The agency has allocated €32.4m (£27.7m) for the initial design phase, with the scientific lead on the mission to be taken by Britain's National Physical Laboratory. The satellite will gain a hi-res view of the greenhouse effect Europe's new space budget to enable CO2 mapping Weather forecasters start using space laser data NPL is the UK's "keeper of standards". It holds references for the kilogram, the metre, the second and all other units used in the international system (SI) of measurement. The lab is the place you go, for example, if you want a precise description of the intensity of a light source - something it's able to gauge using a device called a cryogenic radiometer. And the aim of the Truths mission is to get one of these instruments into orbit. Working in tandem with a hyperspectral camera, the radiometer will make a detailed map of the sunlight reflected off Earth's surface - off its deserts, snowfields, forests and oceans. The map should be of such exquisite quality that it's expected to become the standard reference against which all other imaging spacecraft will want to adjust and correct their own observations. This ought to make it a much simpler task to compare the pictures from different satellites, not just from those missions flying today but also from the ones that have long since been retired and whose data now sits in archives. One of the other big goals of Truths is that in measuring the complete reflectance of the Earth globally, and doing it with such precision, it will establish a kind of "climate fingerprint" that a future version of the satellite, 10 to 15 years' later, can then resample. "By doing that we'll be able to detect subtle changes much earlier than we can with our current observing system," explained NPL's Prof Nigel Fox. "This will allow us to constrain and test the climate forecast models. So we'll know earlier whether the predicted temperatures that the models are giving us are consistent or not with the observations." Invitations to tender for the design work will be sent out to industry shortly. A grand plan for how to implement Truths must be ready for when the research ministers of Esa's member states gather for their next major policy meeting in 2022. The feasibility work will also need to produce a full costing for the project, likely to be in the region of €250-300m (£210-260m). Barring technical showstoppers, the ministers should then green-light the mission for a targeted launch in 2026. Britain will almost certainly bear the majority of the cost of implementing Truths. The UK has been its leading advocate. "It plays to our strengths," said Beth Greenaway, the head of Earth observations and climate at the UK Space Agency. "NPL is remarkable. It does the standard time for the world; it does the standard metre. We like to think of ourselves leading on climate change so we should be providing the standard reference for Earth's radiation budget." Truths is an acronym for Traceable Radiometry Underpinning Terrestrial- and Helio- Studies. It will be sensitive to light in the visible and near-infrared part of the electromagnetic spectrum. Esa recently agreed to implement another UK-led mission called Forum which will map Earth's radiation at longer wavelengths in the far-infrared. https://www.bbc.co.uk/news/science-environment-51197453 Quote
Subscriber CaaC (John)+ Posted January 25, 2020 Author Subscriber Posted January 25, 2020 Space cookies: First food baked in space by astronauts Chocolate chip cookies have become the first food to be baked in space in a first-of-its-kind experiment. Astronauts baked the cookies in a special zero-gravity oven at the International Space Station (ISS) last month. Sealed in individual baking pouches, three of the cookies returned to Earth on the SpaceX Dragon spacecraft on 7 January. The aim of the experiment was to study cooking options for long-haul trips. The results of the experiment, carried out by astronauts Luca Parmitano and Christina Koch, were revealed this week. FULL REPORT Quote
Subscriber CaaC (John)+ Posted January 26, 2020 Author Subscriber Posted January 26, 2020 Astronauts, complete 4-spacewalk marathon to fix space station's $2 billion antimatter detector It took four entire spacewalks to fix. It took four years of planning, 20 new tools shipped by spacecraft and an unprecedented four-part repair job, but a $2 billion experiment on the International Space Station is all patched up after a spacewalk by astronauts Saturday (Jan. 25). NASA astronaut Drew Morgan and European Space Agency astronaut Luca Parmitano spent 6 hours, 16 minutes working outside the station to finish repairs on the ailing Alpha Magnetic Spectrometer, a 9-year-old cosmic ray detector designed to seek out dark matter and antimatter. The instrument, launched in 2011, had lost two of four critical coolant pumps, which the spacewalkers restored. NASA aims to run a series of tests in upcoming days to make sure the repair worked. It wasn't an easy job to perform. Parmitano and Morgan were on the fourth of four spacewalks to fix AMS, completing work that began on the instrument in November. The astronauts were using tools to fix an instrument that was initially, never even designed for spacewalking repairs. On this spacewalk, which was broadcast live on NASA Television, leak drama dominated the early hours of the work. FULL REPORT Quote
Subscriber CaaC (John)+ Posted January 29, 2020 Author Subscriber Posted January 29, 2020 Two satellites set for a close shave over US city of Pittsburgh Two satellites hurtling across the sky at nearly 33,000 mph (53,000 km/h) are predicted to pass dangerously close to one another over Pennsylvania. A group tracking the satellites said it predicted a 1 in 20 chance of a collision, calling it "alarming". The satellites are not in operation, but it is feared a collision could create pieces of debris that would damage other objects in orbit. The last time a major satellite collision occurred was in 2009. The satellites may pass within 40ft (12m) of each other, some 550 miles (900km) above Pittsburgh at around 18:30 local time. LeoLabs, a group that tracks space debris, reported that "it is still unlikely that these objects will collide", but that due to the size of the satellites, the chance of collision had gone up from prior calculations. (More LeoLabs Tweets) FULL REPORT Quote
Subscriber CaaC (John)+ Posted February 1, 2020 Author Subscriber Posted February 1, 2020 Mega-constellation firms meet European astronomers Leading satellite mega-constellations companies SpaceX and OneWeb have met with astronomers in Europe to discuss the impact their operations could have on observations of the Universe. There's concern that the size and brightness of the firms' planned fleets could interfere with the work of professional telescopes. The parties discussed the issues in a private meeting at the Royal Astronomical Society in London, UK. The talks were described "as positive". Present for OneWeb was Dr Timothy Maclay, the start-up's director of mission systems engineering; and for SpaceX, the participant was Patricia Cooper, the California company's vice president of satellite government affairs. OneWeb and SpaceX are in the process of launching big networks of spacecraft to deliver broadband internet to every corner of the globe. The numbers of platforms involved are unprecedented in the history of spaceflight. The RAS gathering was intended as an opening move in what is hoped will become a continuing dialogue. Media were excluded to allow the delegates to have a frank discussion, RAS deputy executive director and press officer, Robert Massey, told BBC News. It's understood two new, soon-to-be-published research studies were presented. One, from the University of Southampton, has investigated the reflectivity of SpaceX's Starlink satellites and what's driving their brightness in the sky. The second, from the European Southern Observatory organisation, has attempted to model how much observing time might be lost by the world's major telescope facilities if the mega-constellations' interference is as bad as some fear it could become. Image captionOneWeb will be launching 34 satellites at once in the coming week Already, astronomers have talked of passing Starlink satellites producing streaks and "ghosting" in telescope images; and of detectors becoming saturated in the glare from the satellites. SpaceX has so far launched 240 satellites in what it says will be an initial constellation of 12,000. OneWeb only has six spacecraft up at the moment but will begin a big roll-out next week. This will see 34 satellites being lofted every month or so until 650 platforms are circling the globe. SpaceX is already in discussions with the American Astronomical Society. It's the wide-field survey telescopes that could suffer most. These will scan large portions of the sky every night looking for opportunity targets such as passing asteroids and exploded stars, but these searches could become compromised if astronomers also have to account for large numbers of confounding artificial light sources. Dr Massey told BBC News: "We appreciated the openness of the two companies; we appreciated the fact that they came to see us and to talk to us. We know that they're not the only operators out there and we need to be having discussions with those people as well. But I think we started to understand some of the genuine quantitative impacts on optical and radio telescopes." The absence of an internationally agreed framework to guide the satellite industry on the brightness of its satellites, giving it some standards to work to, was one of the issues raised at the meeting, Dr Massey added. He contrasted this with the best-practice measures designed to mitigate space debris. Operators are urged to pull defunct spacecraft out of orbit within 25 years to reduce the chances of a collision with active platforms. SpaceX has modified one of its satellites to have a different coating which may help reduce its reflectivity. However, the suspicion is that much of the brightness comes from light bouncing off the long singular solar array incorporated into the Starlink design. The RAS meeting also included representatives from the UK and European space agencies, and from the Square Kilometre Array. Earlier in January, the 235th American Astronomical Society meeting held a special session on the impacts of mega-constellations. https://www.bbc.co.uk/news/science-environment-51334423 Quote
Subscriber CaaC (John)+ Posted February 5, 2020 Author Subscriber Posted February 5, 2020 Greenlight for UK commercial telecoms Moon mission UK satellite company SSTL has got the go-ahead to produce a telecommunications spacecraft for the Moon. The platform, which should be ready for launch in late 2022, will be used by other lunar missions to relay their data and telemetry to Earth. Satellites already do this at Mars, linking surface rovers with engineers and scientists back home. The Lunar Pathfinder venture will do the same at the Moon. SSTL is financing the build of the satellite itself but will sell its telecoms services under a commercial contract with the European Space Agency (Esa). It's hoped other governmental organisations and private actors will purchase capacity as well. The Moon is set to become the go-to destination this decade with the Americans intent on putting humans on the surface again, 50 years after Apollo. Europe's new space budget to enable CO2 mapping Europe keen to demonstrate Moon ambitions To the Moon and beyond: The future of exploration Nasa's Project Artemis has identified 2024 as the date when the "first woman and the next man" will touchdown, close to the lunar south pole. The plan is to put the UK satellite into a highly elliptical orbit so that it can have long periods of visibility over this location. Pathfinder is expected to be particularly useful for any sorties - human or robotic - to the Moon's far side, which is beyond the reach of direct radio transmission with Earth. The UK satellite's presence would make connections possible and this could be the enabler for some smaller, low-cost lunar projects that would otherwise have to procure their own separate relay system. But anywhere at the Moon, above it or on the surface - all missions should benefit from the boost in data rates that comes from a local, dedicated telecoms platform. SSTL says Lunar Pathfinder should be just under 300kg at launch. Its radio payloads will work in S-band and UHF frequencies to talk to nearby spacecraft, and in the X-band to make the back-and-forth connection with Earth. Goonhilly teleport in Cornwall, with its big radio dishes, is anticipated to act as the uplink/downlink station. The Guildford firm is getting this opportunity thanks to the money invested by the UK government in Esa at its recent Ministerial Council in Seville, Spain. The UK Space Agency (UKSA) delegation committed €14m (£12m) to Europe's lunar exploration budget. British representatives also put down €18m (£15m) to be part of efforts to develop an international space station at the Moon called Gateway. Again, the UK is hopeful it can play a role in this station's communications. "This would be to talk from Gateway to surface missions," said Sue Horne, the head of the space exploration at UKSA. "This should be compatible with Lunar Pathfinder. So, you can see our strategy: We'd like to take a lead in deep space communications with Goonhilly, Lunar Pathfinder and Gateway. We're carving out an area for the UK," she told BBC News. Separately, SSTL is working on a feasibility study for Esa looking at how a constellation of spacecraft could be flown around the Moon to provide not just telecoms but also satellite-navigation services for the lunar market (SSTL has been part of the consortium that's built all the spacecraft for Europe's Galileo sat-nav system). Good positioning on the Moon will be relevant as more and more missions visit the surface. "Lunar Pathfinder is a 'pathfinder' - it will prove the technology but also test the viability of a commercial market for telecoms services at the Moon. When the future constellation is launched, Pathfinder will become a node within that network," explained Nelly Offord Harlé, the business manager for exploration at SSTL. SSTL says Lunar Pathfinder should be just under 300kg at launch. Its radio payloads will work in S-band and UHF frequencies to talk to nearby spacecraft, and in the X-band to make the back-and-forth connection with Earth. Goonhilly teleport in Cornwall, with its big radio dishes, is anticipated to act as the uplink/downlink station. The Guildford firm is getting this opportunity thanks to the money invested by the UK government in Esa at its recent Ministerial Council in Seville, Spain. The UK Space Agency (UKSA) delegation committed €14m (£12m) to Europe's lunar exploration budget. British representatives also put down €18m (£15m) to be part of efforts to develop an international space station at the Moon called Gateway. Again, the UK is hopeful it can play a role in this station's communications. "This would be to talk from Gateway to surface missions," said Sue Horne, the head of the space exploration at UKSA. "This should be compatible with Lunar Pathfinder. So, you can see our strategy: We'd like to take a lead in deep space communications with Goonhilly, Lunar Pathfinder and Gateway. We're carving out an area for the UK," she told BBC News. Separately, SSTL is working on a feasibility study for Esa looking at how a constellation of spacecraft could be flown around the Moon to provide not just telecoms but also satellite-navigation services for the lunar market (SSTL has been part of thee consortium that's built all the spacecraft for Europe's Galileo sat-nav system). Good positioning on the Moon will be relevant as more and more missions visit the surface. "Lunar Pathfinder is a 'pathfinder' - it will prove the technology but also test the viability of a commercial market for telecoms services at the Moon. When the future constellation is launched, Pathfinder will become a node within that network," explained Nelly Offord Harlé, the business manager for exploration at SSTL. https://www.bbc.co.uk/news/science-environment-51378320 Quote
Subscriber CaaC (John)+ Posted February 7, 2020 Author Subscriber Posted February 7, 2020 OneWeb: London start-up launches the first big batch of satellites The UK-based OneWeb company has sent 34 satellites into orbit on a single Soyuz rocket from Baikonur in Kazakhstan. The start-up is building a mega-constellation in the sky to deliver broadband internet to all corners of the globe. Six spacecraft were lofted in 2019 to prove the technology, but this year will see big batches of platforms going up on a near-monthly basis. The aim is to have the full network in operation by the end of 2021. OneWeb is in a race with a number of other companies that want to provide the same kind of service. FULL REPORT Quote
Subscriber CaaC (John)+ Posted February 9, 2020 Author Subscriber Posted February 9, 2020 What is Solar Orbiter and what's it going to do? Many scientists are calling it the UK's most important mission for a generation. 1 Quote
Subscriber CaaC (John)+ Posted February 13, 2020 Author Subscriber Posted February 13, 2020 New Horizons spacecraft 'alters theory of planet formation' Scientists say they have "decisively" overturned the prevailing theory of how planets in our Solar System formed. The established view is that material violently crashed together to form ever-larger clumps until they became worlds. New results suggest the process was less catastrophic - with matter gently clumping together instead. The study appears in Science journal and has been presented at the American Association for the Advancement of Science meeting in Seattle. The study's lead researcher, Dr Alan Stern said that the discovery was of "stupendous magnitude". FULL REPORT Quote
Subscriber CaaC (John)+ Posted February 14, 2020 Author Subscriber Posted February 14, 2020 (edited) @nudge, go for it, I am too old. Wanted: New astronauts for Nasa Moon mission https://www.bbc.co.uk/news/world-us-canada-51487871 Edited February 14, 2020 by CaaC (John) 1 Quote
nudge Posted February 14, 2020 Posted February 14, 2020 3 minutes ago, CaaC (John) said: @nudge, go for it, I am too old. Wanted: New astronauts for Nasa Moon mission https://www.bbc.co.uk/news/world-us-canada-51487871 "But as it is a US federal agency, the first requirement to join Nasa is American citizenship." Quote
Subscriber CaaC (John)+ Posted February 14, 2020 Author Subscriber Posted February 14, 2020 1 minute ago, nudge said: "But as it is a US federal agency, the first requirement to join Nasa is American citizenship." Get one of your pals to falsify documents, someone like @Bluewolf 1 Quote
nudge Posted February 14, 2020 Posted February 14, 2020 Just now, CaaC (John) said: Get one of your pals to falsify documents, someone like @Bluewolf I have NASA slippers, maybe they'll make an exception for me based on that 3 Quote
Subscriber Mel81x+ Posted February 14, 2020 Subscriber Posted February 14, 2020 6 minutes ago, nudge said: "But as it is a US federal agency, the first requirement to join Nasa is American citizenship." This, to me, is silly. If you're not able to get enough astronauts in your own country you should hunt elsewhere. I am sure there are so many people who would fit the bill and could be vetted properly. I'd say apply and tell them the only way you will come, when you pass, is if they send you the application with an oak cask aged Whiskey. 1 Quote
Bluewolf Posted February 14, 2020 Posted February 14, 2020 17 minutes ago, CaaC (John) said: Get one of your pals to falsify documents, someone like @Bluewolf As you mention it... got some blank ones knocking about, just need a few details and we are good to go... 1 Quote
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