After several delays, SpaceX has finally launched its 12th Starlink Mission, which brings its internet-beaming satellite constellation to just under the 800 it needs to deliver moderate coverage in North America.
With this latest launch at Tuesday, 7:29 am EDT from the Kennedy Space Center in Florida, SpaceX has now launched 775 Linux-powered Starlink satellites. But, via CBS News, only 728 Starlink satellites remain in orbit, according to astronomer Jonathan McDowell’s latest Space Report.
As noted by Space.com, before Tuesday’s successful Starlink launch, SpaceX had scrubbed four attempted launches due to weather and other issues. SpaceX integration and test engineer Siva Bharadvaj said Tuesday was “a happy end to Scrub-tober”.
SEE: Network security policy (TechRepublic Premium)
More importantly for broadband-starved potential customers in the US, this latest batch of 60 Starlink satellites clears the way for a public beta in northern US and possibly southern Canada.
“Once these satellites reach their target position, we will be able to roll out a fairly wide public beta in northern US and hopefully southern Canada. Other countries to follow as soon as we receive regulatory approval,” tweeted SpaceX CEO Elon Musk.
Starlink has been running a private beta since July in parts of northern US and while it has had coverage of southern Canada, services there are pending regulatory approval. However, the private beta was largely limited to SpaceX employees, according to TechCrunch.
One group Musk said SpaceX has prioritized is emergency services. Last week, the Washington state military’s emergency-management unit revealed it had been using seven Starlink end-user terminals for connectivity since early August in fire-ravaged parts of the state.
In an update after Tuesday’s launch, SpaceX said the way Washington’s first responders deployed Starlink in Malden, just south of Spokane, Washington, is “representative of how Starlink works best – in remote or rural areas where internet connectivity is unavailable”.
The public beta means more would-be Starlink customers, who are looking to ditch sub-par broadband connections, traditional satellite services, and mobile broadband substitutes, will have a chance to test SpaceX’s satellite broadband service.
Starlink satellites orbit Earth at an altitude of about 500km, or 311 miles, far closer to Earth than traditional conventional satellite broadband services.
Richard Hall, the emergency telecommunications leader of the Washington State Military Department’s IT division, vouched for Starlink’s broadband throughput, low latency, and ease of setting up the ‘UFO on a stick’ end-user terminals.
SpaceX in August applied to the Federal Communications Commission to boost the number of end-user terminals it’s permitted to deploy from one million to five million, after 700,000 US residents signed up to be updated about the service’s availability.
SpaceX recently presented the FCC Starlink internet performance tests showing it was capable of download speeds of between 102Mbps to 103Mbps, upload speeds of 40.5Mbps to not quite 42Mbps, and a latency of 18 milliseconds to 19 milliseconds.
However, SpaceX still has some way to go in ramping up production of the end-user terminals. Currently, it has the capacity to produce “thousands of consumer user terminals per month”.
More on Elon Musk’s SpaceX and internet-beaming satellites
Scientists Peer Inside an Asteroid – Is Bennu in the Process of Spinning Itself Into Pieces? – SciTechDaily
New findings from NASA’s OSIRIS-REx mission suggest that the interior of the asteroid Bennu could be weaker and less dense than its outer layers—like a crème-filled chocolate egg flying though space.
The results appear in a study published in the journal Science Advances and led by the University of Colorado Boulder’s OSIRIS-REx team, including professors Daniel Scheeres and Jay McMahon. The findings could give scientists new insights into the evolution of the solar system’s asteroids—how bodies like Bennu transform over millions of years or more.
OSIRIS-REx rendezvoused with Bennu, an asteroid orbiting the sun more than 200 million miles from Earth, in late 2018. Since then, the spacecraft, built by Colorado-based Lockheed Martin, has studied the object in more detail than any other asteroid in the history of space exploration.
So far, however, one question has remained elusive: What’s Bennu like on the inside?
Scheeres, McMahon and their colleagues on the mission’s radio science team now think that they have an answer—or at least part of one. Using OSIRIS-REx’s own navigational instruments and other tools, the group spent nearly two years mapping out the ebbs and flows of Bennu’s gravity field. Think of it like taking an X-ray of a chunk of space debris with an average width about the height of the Empire State Building.
“If you can measure the gravity field with enough precision, that places hard constraints on where the mass is located, even if you can’t see it directly,” said Andrew French, a coauthor of the new study and a former graduate student at CU Boulder, now at NASA’s Jet Propulsion Laboratory (JPL).
What the team has found may also spell trouble for Bennu. The asteroid’s core appears to be weaker than its exterior, a fact that could put its survival at risk in the not-too-distant future.
“You could imagine maybe in a million years or less the whole thing flying apart,” said Scheeres, a distinguished professor in the Ann and H.J. Smead Department of Aerospace Engineering Sciences.
Evolution of asteroids
Of course, that’s part of the fun of studying asteroids. Scheeres explained that Bennu belongs to a class of smaller bodies that scientists call “rubble pile” asteroids—which, as their name suggests, resemble loosely held-together mounds of debris.
Asteroids also change over time more than people think.
“None of them have sat out there unchanging since the dawn of the solar system,” Scheeres said. “They’re being changed by things like sunlight affecting how they spin and collisions with other asteroids.”
To study how Bennu and other similar asteroids may change, however, he and his colleagues needed to take a peek inside.
This is where the team got lucky. When OSIRIS-REx first arrived at Bennu, the spacecraft spotted something unusual: Over and over again, tiny bits of material, some just the size of marbles, seemed to pop off the asteroid and into space. In many cases, those particles circled Bennu before falling back down to the surface. Members of the mission’s radio science team at JPL were able to witness how the body’s gravity worked first-hand—a bit like the apocryphal story of Isaac Newton inferring the existence of gravity after observing an apple falling on his head.
“It was a little like someone was on the surface of the asteroid and throwing these marbles up so they could be tracked,” Scheeres said. “Our colleagues could infer the gravity field in the trajectories those particles took.”
In the new study, Scheeres and his colleagues combined those records of Bennu’s gravity at work with data from OSIRIS-REx itself—precise measurements of how the asteroid tugged on the spacecraft over a period of months. They discovered something surprising: Before the mission began, many scientists had assumed that Bennu would have a homogenous interior. As Scheeres put it, “a pile of rocks is a pile of rocks.”
But the gravity field measurements suggested something different. To explain those patterns, certain chunks of Bennu’s interior would likely need to be more tightly packed together than others. And some of the least dense spots in the asteroid seemed to lie around the distinct bulge at its equator and at its very core.
“It’s as if there is a void at its center, within which you could fit a couple of football fields,” Scheeres said.
Now, thanks to laser altimetry data and high-resolution imagery from OSIRIS-REx, we can take a tour of Bennu’s remarkable terrain. Credit: NASA’s Goddard Space Flight Center
The asteroid’s spin may be responsible for that void. Scientists know that the asteroid is spinning faster and faster over time. That building momentum could, Scheeres said, be slowly pushing material away from the asteroid’s center and toward its surface. Bennu, in other words, may be in the process of spinning itself into pieces.
“If its core has a low density, it’s going to be easier to pull the entire asteroid apart,” Scheeres said.
For the scientist, the new findings are bittersweet: After measuring Bennu’s gravity field, Scheeres and his team have mostly wrapped up their work on the OSIRIS-REx mission.
Their results have contributed to the mission’s sample analysis plan—currently in development. The returned sample will be analyzed to determine the cohesion between grains—a key physical property that affects the mass distribution observed in their study.
“We were hoping to find out what happened to this asteroid over time, which can give us better insight into how all of these small asteroids are changing over millions, hundreds of millions or even billions of years,” Scheeres said. “Our findings exceeded our expectations.”
Read Asteroid Bennu Secrets Unlocked by NASA’s OSIRIS-REx Ahead of Historic Heist for more on this and related research.
“Heterogeneous mass distribution of the rubble-pile asteroid (101955) Bennu” by D. J. Scheeres, A. S. French, P. Tricarico, S. R. Chesley, Y. Takahashi, D. Farnocchia, J. W. McMahon, D. N. Brack, A. B. Davis, R.-L. Ballouz, E. R. Jawin, B. Rozitis, J. P. Emery, A. J. Ryan, R. S. Park, B. P. Rush, N. Mastrodemos, B. M. Kennedy, J. Bellerose, D. P. Lubey, D. Velez, A. T. Vaughan, J. M. Leonard, J. Geeraert, B. Page, P. Antreasian, E. Mazarico, K. Getzandanner, D. Rowlands, M. C. Moreau, J. Small, D. E. Highsmith, S. Goossens, E. E. Palmer, J. R. Weirich, R. W. Gaskell, O. S. Barnouin, M. G. Daly, J. A. Seabrook, M. M. Al Asad, L. C. Philpott, C. L. Johnson, C. M. Hartzell, V. E. Hamilton, P. Michel, K. J. Walsh, M. C. Nolan and D. S. Lauretta, 8 October 2020, Science Advances.
The University of Arizona leads science operations for OSIRIS-REx. NASA’s Goddard Space Flight Center in Maryland manages the overall mission.
Other coauthors on the new study include researchers at the Jet Propulsion Laboratory, Smithsonian Institution, The Open University, Northern Arizona University, KinetX Aerospace, Inc., NASA Goddard Space Flight Center, University of Maryland, Johns Hopkins University, York University, University of British Columbia, Southwest Research Institute, Université Côte d’Azur and University of Arizona.
Geologists might have found a long-lost tectonic plate – Tech Explorist
The existence of a tectonic plate called Resurrection has long been controversial among geophysicists. Some believe that it never existed, while others say that it is subducted into the Earth’s mantle somewhere in the Pacific Margin between 40 and 60 million years ago.
A new study by the University of Houston College of Natural Sciences and Mathematics shed light on this- suggesting that the Resurrection plate existed. Scientists believe they have found the remains of the missing plate, Resurrection in northern Canada-crushed, reshaped, and buried through subduction processes.
For this study, scientists used a technique developed by the UH Center for Tectonics and Tomography called slab unfolding to reconstruct what tectonic plates in the Pacific Ocean looked like during the early Cenozoic Era.
The rigid outermost shell of Earth, or lithosphere, is broken into tectonic plates, and geologists have always known there were two plates in the Pacific Ocean around then called Kula and Farallon. Be that as it may, there has been discussion about a potential third plate, Resurrection, which has shaped a unique volcanic belt along with Alaska and Washington State.
According to scientists, this study could help geologists predict volcanic hazards and mineral and hydrocarbon deposits.
Spencer Fuston, a third-year geology doctoral student, said, “We believe we have direct evidence that the Resurrection plate existed. We are also trying to solve a debate and advocate for which side our data support.”
Using 3-D mapping technology, scientists applied the slab unfolding technique to the mantle tomography images to pull out the subducted plates before unfolding and stretching them to their original shapes.
Jonny Wu, assistant professor of geology in the Department of Earth and Atmospheric Sciences, said, “When ‘raised’ back to the Earth’s surface and reconstructed, the boundaries of this ancient Resurrection tectonic plate match well with the ancient volcanic belts in Washington State and Alaska, providing a much sought after link between the ancient Pacific Ocean and the North American geologic record.”
- Spencer Fuston et al., Raising the Resurrection plate from an unfolded-slab plate tectonic reconstruction of northwestern North America since early Cenozoic time, GSA Bulletin (2020). DOI: 10.1130/B35677.1
Researchers rediscover tectonic plate lost for 60 million years – lintelligencer
The existence of a tectonic plate called Resurrection has long been a topic of debate among geologists, with some arguing it was never real. Others say it subducted – moved sideways and downward – into the earth’s mantle somewhere in the Pacific Margin between 40 and 60 million years ago.
A team of geologists at the University of Houston College of Natural Sciences and Mathematics believes they have found the lost plate in northern Canada by using existing mantle tomography images – similar to a CT scan of the earth’s interior. The findings, published in Geological Society of America Bulletin, could help geologists better predict volcanic hazards as well as mineral and hydrocarbon deposits.
“Volcanoes form at plate boundaries, and the more plates you have, the more volcanoes you have,” said Jonny Wu, assistant professor of geology in the Department of Earth and Atmospheric Sciences. “Volcanoes also affect climate change. So, when you are trying to model the earth and understand how climate has changed since time, you really want to know how many volcanoes there have been on earth.”
Wu and Spencer Fuston, a third-year geology doctoral student, applied a technique developed by the UH Center for Tectonics and Tomography called slab unfolding to reconstruct what tectonic plates in the Pacific Ocean looked like during the early Cenozoic Era. The rigid outermost shell of Earth, or lithosphere, is broken into tectonic plates and geologists have always known there were two plates in the Pacific Ocean at that time called Kula and Farallon. But there has been discussion about a potential third plate, Resurrection, having formed a special type of volcanic belt along Alaska and Washington State.
“We believe we have direct evidence that the Resurrection plate existed. We are also trying to solve a debate and advocate for which side our data supports,” Fuston said.
Using 3D mapping technology, Fuston applied the slab unfolding technique to the mantle tomography images to pull out the subducted plates before unfolding and stretching them to their original shapes.
“When ‘raised’ back to the earth’s surface and reconstructed, the boundaries of this ancient Resurrection tectonic plate match well with the ancient volcanic belts in Washington State and Alaska, providing a much sought after link between the ancient Pacific Ocean and the North American geologic record,” explained Wu.
Post-lignite investment projects of €4 bln | Business | ekathimerini.com – www.ekathimerini.com
Lee Kun-Hee, force behind Samsung's rise, dies at 78 – Business News – Castanet.net
Vote to review Liberals response to COVID-19 highlights showdown between politics and science – National Post
Silver investment demand jumped 12% in 2019
Iran anticipates renewed protests amid social media shutdown
Galaxy M31 July 2020 security update brings Glance, a content-driven lockscreen wallpaper service
- Politics24 hours ago
'Escape the politics': B.C. clinics headhunt Alberta doctors – Calgary Herald
- Economy19 hours ago
Time to Reset Expectations for World Economy With Virus Untamed
- News21 hours ago
Ontario reports record 978 new COVID-19 cases
- Economy20 hours ago
World Economy Gets Temperature Check Before U.S. Vote: Eco Week
- Tech20 hours ago
MagSafe Chargers Might Leave Imprints on Leather Cases, Warns Apple
- Media21 hours ago
Kelowna woman learns lesson from public shaming on social media
- Health20 hours ago
COVID infections in B.C. remain at elevated levels on Friday with 223 new cases
- Sports20 hours ago
Rays walk-off Game 4 to even World Series against Dodgers