Ars Technica South Africa
Rocket Report: An old Centaur comes home, Super Heavy construction begins - Ars Technica
“We can launch rockets that have satellites into space from right here in Queensland.”
Enlarge/ The Delta IV Heavy rocket lit up the night sky on Wednesday night, but not by launching. 64 with 35 posters participating, including story author Welcome to Edition 3.18 of the Rocket Report! I'm thrilled this week to announce that I've written a book about the origins of SpaceX. It focuses on the Falcon 1 rocket, Elon Musk, and the early employees who carried out his vision. I spent oodles of time with Musk, who was expansive about those early years. But just as importantly, I talked to dozens of the first SpaceX employees about those desperate days. Liftoff tells their story, and it is one hell of a tale. The book will be published by William Morrow on March 2, 2021. You can preorder now. As always, we welcome reader submissions, and if you don't want to miss an issue, please subscribe using the box below (the form will not appear on AMP-enabled versions of the site). Each report will include information on small-, medium-, and heavy-lift rockets as well as a quick look ahead at the next three launches on the calendar. German company tests hybrid rocket motor. Two-year-old launch startup HyImpulse successfully tested its 16,800 lbf hybrid rocket motor this month at the German space agency's Lampoldshausen facility, SpaceNews reports. The company said the hot-fire test on September 15, its first, confirmed that the paraffin/LOX hybrid rocket engine performed on par with liquid hydrocarbon-based fuels. An important engine ... HyImpulse is developing its three-stage "SL1" launch vehicle designed to carry payloads of up to 500kg to Sun-synchronous orbit. The rocket will be powered by 12 identical 16,800 lbf hybrid rocket motorseight on its first stage, and four on its second stageplus four smaller versions of the engines powering its third stage. (submitted by platykurtic and Ken the Bin) Another German startup picks a launch site. Rocket Factory Augsburg AG has signed a Memorandum of Understanding with Norway-based Andøya Space to implement a launch site for the RFA One rocket and provide end-to-end launch services for small satellites. "This partnership is pivotal, it allows RFA and Andøya to launch the first satellite into orbit from continental Europe with an European launcher" said Dr. Stefan Brieschenk, chief operation officer of RFA, in a news release. A bigger small rocket ... The startup is backed by the German satellite manufacturer OHB as a strategic investor and by Munich-based venture capital firm Apollo Capital Partners. Rocket Factory is currently building the RFA One booster to deliver up to 1.5 metric tons to low-Earth orbit. The first launch is scheduled for 2022. There is an interesting ongoing race in Germany among small-launch startups, including RFA, HyImpulse, and Isar Aerospace. (submitted by Ken the Bin) The easiest way to keep up with Eric Berger's space reporting is to sign up for his newsletter, we'll collect his stories in your inbox. Space becomes a bona fide political issue in Australia. We are not on top of Australian politics, but the opposition Liberal National Party of Queensland is apparently running on a platform that includes the accelerated development of a spaceport on islands along the country's northeast coast. Opposition leader Deb Frecklington has pledged $15 million to build an orbital rocket launch site at Abbot Point in north Queensland, the Brisbane Times reports. Gotta go fast ... The Labor government is moving too slowly on the project, opponents say. An LNP government would start building the government-owned site next year, which would create 100 construction jobs, Frecklington said, and another 200 jobs would come from securing Gilmour Space Technologies as the anchor tenant. "This means that we can launch rockets that have satellites into space from right here in Queensland," she said. "Make no mistake, if these rockets with their satellites are not launched from Queensland, they are going to be launched out of Cape Canaveral in the US." Or, presumably, New Zealand. (submitted by Cognac) Maine company sets launch date for small rocket. Brunswick-based bluShift Aerospace plans to launch its 20-foot rocket in October. The launch location, at the site of a former Naval Air Station, is in far northern Maine. The company is targeting October 21 for the launch of its Stardust rocket to an altitude of 4,500 feet. Showing, not telling ... The company is developing biofuel rockets, and this test will provide data about the performance of this fuel. "We learned early on in our research and development that having an engine that used a green fuel was not enough to inspire investment," bluShift CEO Sascha Deri told the Times Record. "We had to demonstrate that we could match or beat the petroleum alternative." We wish them luck! (submitted by Jenming) Skyroot unveils 3D-printed engine. The commercial launch startup based in India shared images of its Dhawan-1 cryogenic engine to mark the 100th anniversary of the birth of Indian rocket pioneer Satish Dhawan. The "100 percent" 3D-printed engine will be powered by liquified natural gas and liquid oxygen, Parabolic Arc reports. Another honorary name ... The company says it is developing three rocketsthe Vikram I, Vikram II, and Vikram IIIto serve the small-satellite launch market. The smallest rocket will have a capacity of 225kg to a Sun-synchronous orbit, while the largest will carry up to 580kg. The launch vehicles are named for Vikram Sarabhai, who is known as the father of the Indian space program. (submitted by Ken the Bin and platykurtic) Speaking of Indian launch history. If you're like me, you probably don't know all that much about India's history with regard to space and launch. (I can barely keep my US and Soviet history straight). However, if you're into podcasts, there's a fascinating new one titled Mission to ISRO that dives deep into this past. Great context for modern-day activity ... Narrated by Harsha Bhogle, the podcast is targeted at those with a basic knowledge of space history but no knowledge whatsoever of Indian launch history (raises hand). So if you're wondering who Vikram Sarabhai was and why an Indian startup is naming rockets after him, this is a good place to start. I've been loving it. Alas, it's exclusive to Spotify. Space Force agrees to fly on used Falcon 9s. Last Friday, the US Space Force said it would launch two critical Global Positioning System missions on used Falcon 9 rockets next year, Ars reports. Doing so will save the military $52 million, officials said, as SpaceX agreed to lower compensation for the two missions in return for flying used hardware. A continuing journey ... This represents a significant step by the Space Force toward validating the use of flight-proven first stages of a rocket for the most critical national security missions. "We're looking forward to this journey with SpaceX as we get even more experienced with them and reusable hardware," said Walter Lauderdale, Space and Missile Systems Center Falcon Systems and Operations Division chief, in a call with reporters. Next Crew Dragon launch moves to Halloween. NASA and SpaceX now are targeting 2:40am ET (06:40 UTC) on Saturday, October 31, for the launch of the agency's SpaceX Crew-1 mission with astronauts to the International Space Station. This is an eight-day slip from the previous date but is not due to a hardware issue, the space agency said. Closing open work ... Rather, NASA sought to deconflict the Crew-1 launch and arrival from upcoming Soyuz launch and landing operations. This additional time is needed to ensure closure of all open work, both on the ground and aboard the station, ahead of the Crew-1 arrival. In the coming weeks, Ars will have more on this exciting mission carrying four astronauts. (submitted by TFargo04, Ken the Bin and platykurtic) DARPA awards contract for nuclear-thermal rocket. The Defense Advanced Research Projects Agency has awarded a $14 million task order to Gryphon Technologies, a company in Washington, DC, to design a nuclear thermal rocket for cislunar operations, Space.com reports. This was the result of a contracting process that opened in June. A lot of work ahead ... The money will support DARPA's Demonstration Rocket for Agile Cislunar Operations program, whose main goal is to demonstrate a nuclear thermal propulsion system in space. "We are proud to support DRACO and the development and demonstration of NTP, a significant technological advancement in efforts to achieve cislunar space awareness," Gryphon CEO PJ Braden said. (submitted by Rick)
Charlie Bolden says the quiet part out loud: SLS rocket will go away - Ars Technica
“At some point, commercial entities are going to catch up.”
NASA Administrator Charles Bolden speaks in front of Falcon 9 rocket. 70 with 54 posters participating, including story author Charlie Bolden, a four-time astronaut, served as NASA administrator from mid-2009 through early 2017. During that time, he oversaw the creation and initial development of the agency's large Space Launch System rocket. Although some NASA officials such as then-Deputy Director Lori Garver were wary of the rocket's costsabout $20 billion has now been poured into development of a launch vehicle based on existing technologyBolden remained a defender of the large rocket, calling it a lynchpin of the agency's plans to send humans beyond low-Earth orbit, perhaps to the Moon or Mars. He also dismissed the efforts of commercial space companies like SpaceX to build comparable technology. When I sat down with Bolden for an interview in 2014 at Johnson Space Center, I asked why NASA was investing so much in the SLS rocket when SpaceX was using its own funds to develop the lower-cost Falcon Heavy rocket. His response at the time: Lets be very honest. We dont have a commercially available heavy-lift vehicle. The Falcon 9 Heavy may some day come about. Its on the drawing board right now. SLS is real. Two years later, in 2016, Bolden said he still did not believe commercial companies were up to the task. "If you talk about launch vehicles, we believe our responsibility to the nation is to take care of things that normal people cannot do, or dont want to do, like large launch vehicles," Bolden said. "Im not a big fan of commercial investment in large launch vehicles just yet." Since that time, a lot has changed. In February, 2018, SpaceX launched the Falcon Heavy rocket for the first time. It has since flown successfully two more times, and it will play a role in NASA's future exploration plans. Meanwhile, the SLS rocket, originally due to launch in 2017, is now delayed until at least the end of 2021. As a result of this, Bolden appears to have changed his mind. In an interview with Politicopublished Friday morning in the publication's Space newsletter, Bolden was asked what might happen during the next four years. SLS will go away," he said. "It could go away during a Biden administration or a next Trump administration because at some point commercial entities are going to catch up. They are really going to build a heavy lift launch vehicle sort of like SLS that they will be able to fly for a much cheaper price than NASA can do SLS. Thats just the way it works. Bolden remains a popular and influential voice in the space community, but he no longer has a direct say in US space policy. Perhaps because he no longer has to answer to Congress for NASA budgets, he is also free to speak his mind. In any case, his comments reflect the general sentiment in the space communityat least outside of the traditional contractors like Boeing and Northrop Grumman who directly benefit from SLS developmentthat the SLS rocket will eventually go away. The Falcon Heavy is not as capable as the SLS rocket, but its success has clearly demonstrated that private companies can build large, powerful rockets. Moreover, it's not just SpaceX, but also Blue Origin with its New Glenn booster, that seeks to build heavy lift rockets with private money. And although they are rivals, SpaceX's Elon Musk and Blue Origin's Jeff Bezos both agree that rockets need to be capable of reuse to be viable. The SLS will cost about $2 billion to launch and then fall into the ocean. If you're wondering what commercial space proponents really think about the SLS rocket due to its cost and expendability, it's this, which comes from a senior official at a new space company: "If Santa Claus arrived, and said, 'I have good news. It now works and you can launch tomorrow. Everything's done. You're going to have a launch tomorrow.' ... It still isn't getting us to the Moon. Even if they achieve everything they aim for, it still does not get people to the Moon. It certainly does not get a base on the Moon and absolutely doesn't get humans to Mars." When Congress conceived of the Space Launch System rocket in 2010 and directed NASA to build it, they were making two bets. First, they bet the new space companies such as SpaceX would fail. This was a reasonable bet back then, as SpaceX had lost most of the rockets it had tried to launch into space. Second, they bet that traditional companies like Boeing would be better at building big rockets. The Congressional lawmakers who created SLSit began with Florida Senator Bill Nelson and Texas Senator Kay Bailey Hutchison, and they were soon joined by Alabama Senator Richard Shelbylost both of those bets. So now, NASA is building a large, expendable rocket that has cost taxpayers tens of billions of dollars. Congress remains as committed as ever, both in budgets and public statements of support. However, the more that new rockets fly, the more difficult this support will be to maintain. Ironically, NASA and the SLS prime contractor Boeing are no longer competing with the Falcon Heavy. SpaceX beat them 2.5 years ago. Rather, NASA is competing with SpaceX's next rocket, the Super Heavy booster that will loft Starship into orbit. SpaceX has not even built a single segment of its Super Heavy rocketwhich is larger than SLS, more powerful, vastly cheaper, and reusablebut it's possible that the vehicle makes an orbital launch before the decade-old SLS in 2021.
Rocket Report: Delta IV Heavy gets a new date, SpaceX to destroy test tank - Ars Technica
“We believe the current providers address the plans we have today for the near future.”
Enlarge/ Rocket Lab launches its "I Can't Believe It's Not Optical" mission on August 31. 52 with 30 posters participating Welcome to Edition 3.15 of the Rocket Report! The realm of small lift overflows with news in this edition. And as usual, our report covers news from around the world, spanning this week from Germany, to China, to India, to South America. Ours is a global enterprise. As always, we welcome reader submissions, and if you don't want to miss an issue, please subscribe using the box below (the form will not appear on AMP-enabled versions of the site). Each report will include information on small-, medium-, and heavy-lift rockets as well as a quick look ahead at the next three launches on the calendar. Rocket Lab launches a Photon satellite. The launch company said it has sent its first in-house-designed and -built operational satellite into orbit. "First Light" was deployed to orbit on Rocket Lab's 14th Electron mission, "I Can't Believe It's Not Optical," which lifted off from Launch Complex 1 in New Zealand on August 31. The mission's primary customer was a 100kg microsatellite for Capella Space. Not just a rocket company anymore ... Photon's launch cements the company's "evolution from a launch provider to an end-to-end space solutions company that offers turnkey satellites and spacecraft components, launch, and on-orbit," a news release said. Photon is designed to provide in-space services such as power and propulsion to satellites, even allowing for deep-space missions to the Moon and Venus. (submitted by Ken the Bin) Virgin Galactic sets date for next test flight. Virgin Galactic plans to conduct its next crewed spaceflight test on October 22, according to documents the company filed with the Federal Communications Commission, CNBC reports. This flight will likely be the first of two that the space tourism company has planned to complete testing of its SpaceShipTwo spacecraft system, and it should have just two test pilots on board. Commercial service, finally, next year? ... Virgin Galactic said last month that the second test spaceflight, for which no date has yet been set, will have four "mission specialists" inside the cabin. If both test flights succeed, Virgin Galactic expects to fly founder Sir Richard Branson in the first quarter of 2021. This milestone flight would mark the beginning of the company's commercial tourism service. (submitted by Ken the Bin, JohnCarter17, and DanNeely) The easiest way to keep up with Eric Berger's space reporting is to sign up for his newsletter, we'll collect his stories in your inbox. LandSpace raises $175 million. Chinese launch firm LandSpace has raised $175 million in series C+ round funding for development of its Zhuque-2 series of methane/liquid-oxygen launch vehicles, SpaceNews reports. The funding comes two weeks after Chinese competitor launch firm iSpace secured $173 million in series B funding. Both are impressive cash hauls that signal serious intent. A powerful small rocket ... LandSpace is working toward an inaugural launch of the Zhuque-2 in June 2021. The 49.5-meter-tall, two-stage Zhuque-2 will be capable of delivering 4,000kg to a 200km low-Earth orbit or 2,000 kilograms to 500kg Sun-synchronous orbit, according to LandSpace. (submitted by platykurtic and Ken the Bin) NASA sounding rocket launches DUST-2 mission. A two-stage Black Brant IX suborbital sounding rocket launched on Tuesday from White Sands Missile Range in New Mexico carrying the DUST-2 science mission. NASA said the rocket launched the payload to an apogee of approximately 346km before descending back to Earth by parachute. Cheap access to microgravity ... DUST-2's goal is to study how individual atoms, shed by dying stars and supernovae, stick together. When they do, the atoms form dust grainssome of the basic building blocks of our universe. "What we're trying to do is duplicate what happens in at least two astrophysical environments," said principal investigator Joe Nuth, a planetary scientist at NASA's Goddard Space Flight Center. (submitted by JohnCarter17) Blue Origin vets start several new companies. Blue Origin turned 20 years old this week, and although the privately held company hasn't yet put people into space or put a rocket into orbit, it has spawned a new generation of space startups, Cosmic Log reports. Relativity Space is fairly well known, but more companies are currently emerging from semi-stealth mode. Launch and in-space propulsion ... One of them, Stoke Space Technologies, appears to be working on technology to enable the reuse of upper stages. Reach Space Technologies seems to be a propulsion company. And Starfish Space says it is working on an "on-demand, in-space transportation service." We'll add all of them to our list of companies to track! (submitted by Ken the Bin and BH) Brazil launch site evaluating proposals. The Brazilian Space Agency says it has begun evaluating 11 proposals from companies interested in launching rockets from the Alcântara Space Center, located on the country's northern Atlantic coast. The site, at just 2 degrees south of the equator, offers prime territory from which to launch equatorial missions. Turning to commercial use ... Following an initial analysis, the companies will have until October 30, to finalize their proposals, Parabolic Arc reports. It is not clear how many companies the Brazilian spaceport will accept, but it seems likely to prioritize companies with mature, or nearly mature, rocket designs. The spaceport has been used, until now, primarily for military launches. (submitted by Ken the Bin) Australian rocket firm signs Aussie payload. Gilmour Space Technologies says it has signed an Australian customer for the first launch of its Eris rocket, no earlier than 2022. Space Machines Company has contracted to launch a 35kg spacecraft to orbit. "This could well be the first Australian payload to be launched to orbit on an Australian rocket, from an Australian launch site," said Adam Gilmour, co-founder and CEO of Gilmour Space. Talking a big game by the middle of the decade ... The first Eris rockets are advertised as having the capacity to launch payloads up to 305kg into low-Earth orbit and 215kg into 500km Sun-synchronous orbits. The company says its goals are to reach a flight rate of 12 launches a year by 2025 and to help spur a broadening of the Aussie space industry. (submitted by Ken the Bin and platykurtic) Germany considers North Sea launch facility. The German government is studying a proposal from German industry to create a mobile launch pad for satellites in the North Sea. Under the plan, small satellites weighing up to one tonne would be launched with German-built rockets. The Federation of German Industries is lobbying for the project, the BBC reports. A good spot for polar launches ... The pad would be a public-private partnership. German media quote the BDI proposal as saying, "a German launchpad is technically feasible and makes strategic and economic sense." Among the companies that could potentially launch from the platform is Isar Aerospace. (submitted by cpushack, Ken the Bin, and JohnCarter17) China launches a secretive spaceplane. Following months of low-key preparations at the Jiuquan Satellite Launch Center, China launched an experimental reusable spacecraft on Friday, SpaceNews reports. A Long March 2F launch vehicle delivered the spacecraft into orbit following launch at an unspecified time. Maybe an X-37B clone? ... "After a period of in-orbit operation, the spacecraft will return to the scheduled landing site in China. It will test reusable technologies during its flight, providing technological support for the peaceful use of space," the Xinhua report stated following the launch. The plane landed after about two days in space. This Twitter thread by NPR's Geoff Brumfiel provides more interesting details about where the mission landed. (submitted by Ken the Bin) Chandrayaan-3 Moon mission may launch next year. India's "Chandrayaan-3" lunar mission is likely to be launched in the first quarter of 2021, DNA India reports. After the Chandrayaan-2 mission was lost last September, the Indian space agency said it would try again to make a soft landing on the Moon's surface. Enter Chandrayaan-3 ... Because the orbiter launched with the Chandrayaan-2 mission remains functional, this follow-up launch will only carry a lander. It is expected to launch on a GSLV Mark III rocket from India's Satish Dhawan Space Center, and India will attempt to become just the fourth country to make a soft landing on the Moon. (submitted by JohnCarter17) China still has a toxic rocket problem. On Monday, a Long March 4B rocket launched from China's Taiyuan Satellite Launch Center carrying a remote-sensing satellite. This 50-year-old spaceport is located in north-central China, about 500km to the southwest of Beijing. As often happens with the first stages of Chinese rockets launching from the inland Taiyuan facility, the spent Long March 4B booster fell downstream of the spaceport. In this case, it landed near a school and created a predictably large cloud of toxic gas. Living the hydrazine dream (or nightmare) ... The use of hydrazine as a fuel for launch vehicles has been phased out for most of the world, Ars reports. The last major US rocket to use hydrazine was United Launch Alliance's Delta II rocket, which used the toxic fuel in its second stage. Yet the majority of China's launch fleet is powered by hydrazine fuel and nitrogen tetroxide oxidizer. This includes its human-rated Long March 2F rocket as well as the widely used Long March 4 family. Delta IV Heavy launch reset for September 18. United Launch Alliance teams have determined the cause behind a Delta IV Heavy rocket's dramatic, last-second abort late last month, Florida Today reports. This sets the stage for another attempt no earlier than a week from Friday, and an exact time has not been released. This will be the third attempt to launch the NROL-44 classified mission. Rip in the regulator ... On August 29, a torn diaphragm in one of three pressure regulators at Cape Canaveral Air Force Station's Launch Complex 37 caused the computer-controlled scrub just three seconds before liftoff, ULA CEO Tory Bruno said via Twitter on Wednesday. The engines briefly lit on fire, but the rocket remained firmly on the pad. (submitted by BH and JohnCarter17) Military takes wait-and-see approach to super-heavy lift. The US military is happy with the current offerings from United Launch Alliance and SpaceX, but it is keeping an eye on future super-heavy rockets under development. That's according to comments made this week by Brig. Gen. D. Jason Cothern, who oversees launch services procurement for the US Space Force (SpaceNews reported on his comments). If you build it, will they come? ... "We believe the current providers address the plans we have today for the near future." That's what Gen. Cothern said in response to a viewer's question on the potential military value of super-heavy-lift vehicles like Starship and New Glenn, which are being developed to fly to the Moon and beyond. As to what might be required in the next generation of launch vehicles, "as the lead acquirers for military space, it's a question that's dear to us," Cothern said. (submitted by JohnCarter17 and platykurtic) SpaceX may roll a test tank to pad this week. The next tests at SpaceX's Boca Chica facility are likely to involve a test tank rather than a full-scale Starship prototype, NASASpaceflight.com reports. This "SN7.1" model is a larger test tank than its predecessor, SN 7, and made from 304L-series stainless steel (or at least a variant of that alloy). It is likely to be pushed to the bursting point so that SpaceX engineers can understand its limits. Prepping for another pop ... While 304L may not be the "final" alloy SpaceX is hoping to utilize on Starships and Super Heavies in the longer-term future, all previous Starships have been made from the 301-series alloy. Future versions, beginning with SN8, will use the new alloy. With two launch mounts available, it remains to be seen if SN7.1 will take up residence on Starship's regular mount or the second test mount. (submitted by platykurtic) Sept. 11: Rocket 3.1 | Astra demonstration mission | Kodiak Spaceport, Alaska | 02:00 UTC Sept. 17: Falcon 9 | Starlink-12 mission| Kennedy Space Center, Fla. | 18:17 UTC Sept. 18: Delta IV Heavy | NROL-44 | Cape Canaveral, Fla.| TBD
New gravitational-lensing study hints at problems for dark matter models - Ars Technica
On a fine scale, the Universe seems lumpier than it should be.
Enlarge/ The massive galaxy cluster MACSJ 1206. Embedded within the cluster are the distorted images of distant background galaxies, seen as arcs and smeared features. 25 with 22 posters participating While the idea of dark matter was originally proposed to explain the structure of galaxies, one of its great successes was explaining the nature of the Universe itself. Features of the Cosmic Microwave Background can be explained by the presence of dark matter. And models of the early Universe produce galaxies and galaxy clusters by building on structures formed by dark matter. The fact that these models get the big picture so right has been a strong argument in their favor. But a new study suggests that the same models get the details wrongby an entire order of magnitude. The people behind the study suggest that either there's something wrong with the models, or our understanding of dark matter may need an adjustment. Under a lens The new study, performed by an international team of researchers, took advantage of a phenomenon called gravitational lensing. Gravity warps space itself, and it can do so in a way that bends light, analogous to a lens. If a massive objectsay, a galaxysits between us and a distant object, it can create a gravitational lens that magnifies or distorts the distant object. Depending on the precise details of how the objects are arranged, the results can be anything from a simple magnification to circular rings or having the object appear multiple times. Because dark matter's effects are detectable via gravity, we can "see" the presence of dark matter via its gravitational-lensing effects. In a few cases, we've even detected lensing where little matter is present. That's one of the many pieces of evidence in favor of dark matter. The researchers used gravitational lensing to set up a test that, at least conceptually, was very simple. We've built models of the early Universe that indicate how dark matter helped structure the first galaxies and drew them into clusters of galaxies. These models, when run forward, provide a description of what that dark matter distribution should look like at different points in the Universe's history up to the present. So the researchers decided to use gravitational lensing to determine whether the dark matter distribution seen in the models matched where we see it via gravitational lensing. According to these models, the Universe was built hierarchically. Via gravitational interactions with itself, dark matter formed filaments that intersected in a complex, three-dimensional meshwork. The additional gravitational pull at the points where filaments intersected would draw in regular matter, leading to the first galaxies. Over time, the continued draw of gravity pulled galaxies together, forming large clusters. By examining the output of these models, we can get a look at the expected distribution of dark matter around clusters. And by zooming in, we can see how dark matter should be distributed in the area of individual galaxies. That distribution of dark matter can be viewed as a prediction of the models. Meanwhile, in the actual Universe... To test those predictions, the researchers used images from the Hubble space telescope to map out all the objects in and around a large collection of galaxy clusters. Follow-up imaging using the Very Large Telescope helped identify the distance of those objects based on how much their light was shifted to the red end of the spectrum by the expansion of the Universethe larger the redshift, the more distant the object. This allowed the researchers to determine which objects must be behind the galaxy cluster and thus potential candidates for gravitational lensing. A software package then used the data to create a mass distribution for each galaxy cluster. This included the overall lensing effects of the entire cluster, as well as the sub-lensing driven by individual galaxies within the cluster. The researchers found a strong agreement between the appearance of lensed objects and the location of individual galaxies, which allowed them to validate their mass-distribution calculations. The researchers then used the Universe simulator to build 25 simulated clusters and performed a similar analysis with the clusters. They did so in order to identify the sites of possible lensing and the locations that could create the greatest distortions. The two didn't match. There were significantly more areas that generated high distortion in the real-Universe galaxy than there were in the model. This would be the case if the distribution of dark matter were a bit more lumpy than the models would predictthe dark matter halos around galaxies were more compact than the models would predict. This isn't the first discrepancy of the sort we've seen. Dark matter models also predict that there should be more dwarf satellite galaxies around the Milky Way and that they should be more diffuse than they are. But if we were to adjust our models to make these galaxies more diffuse, we'd be less likely to see more compact structures in galaxy clusters. So rather than finding two problems that could both be solved by making one adjustment, the two issues appear to need adjusting in opposite directions. Two possibilities The researchers suggest there are two likely explanations for this discrepancy: either we don't appreciate all the properties of dark matter or there's something missing from our simulations of the Universe's evolution. Since both of those get the big picture of the Universe largely right, however, the issue is going to be a subtle one and consequently difficult to identify, should these results get an independent confirmation. One possibility is that the problems seem to be in the area of galaxies, where there would be a lot of matter-dark matter interactions. If there's something more complicated going on there, it could easily throw off the models. For now, however, there are already likely to be teams with additional data in hand that could perform similar analysis, so we'll have to wait for those to be done. Theoretical cosmologists, being the impatient sort, will undoubtedly be testing out dark matter variants long before any additional reanalyses are out. Science, 2020. DOI: 10.1126/science.aax5164 (About DOIs).
Planet X? Why not a tiny black hole instead? - Ars Technica
Unsuccessful at finding planet X? Substitute with undetectable black hole.
20 with 17 posters participating Planet X has a long and storied history of non-existence. For about 130 years, astronomers have debated the existence of an additional planet or planets to explain discrepancies in the orbits of the known planets (mainly Neptune and Uranus). Later, the list of discrepancies was expanded to cover trans-Neptunian objects. But none of the Planet X candidates discovered, including Pluto, have the mass or location to explain observations. Primordial black holes have now been proposed as the latest planet X (or planet 9, since Pluto was demoted). Orbital weirdness Planet Xs origin starts with the discovery of Neptune. Neptune was not found by accident: observations of oddities in the orbit of Uranus were used to calculate the location of Neptune, and it was subsequently found. That is a game that can be played more than once. Astronomers then noted that Uranus and Neptunes orbits could be better explained by the existence of another large planet. Follow-up observations have found numerous objects: Pluto and Charon, Sedna, and Eris to name a few. None of these far-flung bodies is large enough to be planet X. But some of their orbits may also suggest a new planet is needed. Some trans-Neptunian objects have very weird orbits. Many are clustered and have highly elliptical orbits, and there is a sub-group that orbits well out of the plane in which the planets orbit. Thats unusual, since the action of gravity and the nature of the disc that formed the planets typically keeps everything close to the same orbital plane. Finding highly inclined orbits suggests that something is pulling the objects back out of the plane. A planet that is large and far enough from the Sun might explain these orbits. Indeed, researchers have calculated a range of different planet masses and orbits that may account of the behavior of objects like Sedna. By happy coincidence, the required masses and distances correspond to an observed gravitational lensing anomalyan excess of events where the gravitational influence of an unseen object distorted the light from distant stars. That is, there is mass out there, and it is unseen. Could this be a new planet? A series of unlikely events So, there seems to be mass, but where did it come from? The planet would have to be something like 300-1,000AU from the Sun (for reference, Neptunes orbit is just 30AU), where there is very little rock or gas. Simply put, a planet could not form out there. One possibility is that the planet formed closer the Sun and was ping-ponged out there by interactions with one or more of the gas giants. However, to stabilize at a distant orbit, a passing star (or something similar) is required, which seems unlikely. The remaining option is that our Sun captured a freely wandering planet. But wanderers need to have been expelled from their own solar system, meaning that most of them are moving at a fair clip. Hence, the chance of capturing such a planet in the required orbit is low, although not impossible. The new paper argues that, if we are looking at a low-probability event, why not a primordial black hole? Primordial black holes might have formed shortly after the Big Bang. And, unlike black holes formed from collapsing stars, they could have masses ranging from tiny (10µg) on upwards. That means there should be a few with the right mass range. How many is a matter of speculation. Drawn in by the idea, the researchers started rolling d20s: they set primordial black holes to an arbitrary low number and then concluded that capturing a black hole is about as likely as capturing a wandering planet. In for a penny, in for a pound If planet X were indeed a black hole, how would we know? The researchers argue that dark-matter annihilation is the thing to search for. No one knows if primordial black holes exist. No one knows if dark matter annihilates, and if it does, there is no certainty that it does so in a way that is detectabledark matter could annihilate with itself to create other forms of dark matter, leaving us, well, in the dark. Thus, a speculative product of the early Universe cannot be directly detected unless another speculative process happens to occur in the right manner. In which case, it is possible to confirm if a primordial black hole is part of our solar system family. Underlying the speculation is an interesting coincidence: unexplained gravitational lensing events that happen to be the right mass and distance to explain some very odd orbits of trans-Neptunian objects. That coincidence feels like it cries out for a single explanation, which is what the researchers are trying to do. That makes their house of cards useful. Physical Review Letters, 2020, DOI: 10.1103/PhysRevLett.125.051103 (About DOIs)
People slept on comfy grass beds 200,000 years ago - Ars Technica
The earliest members of our species slept on piles of grass alongside warm hearth fires.
31 with 27 posters participating Fragments of glassy petrified grass and microscopic traces of plant material, dating to around 200,000 years ago, are all thats left of a Paleolithic hunter-gatherers bed in the back of Border Cave. In the same part of the rock shelter, archaeologists found layers of ash with more recent (as in only around 43,000 years old) and better-preserved leaves of dried grass laid on top, as if people had burned their old, dirty bedding and then laid fresh, clean sheaves of grass over the ashesthe rock shelter version of changing the sheets. The finds shed light on an aspect of early human life that we rarely get to consider. Most of the artifacts that survive from more than a few thousand years ago are made of stone and bone; even wooden tools are rare. That means we tend to think of the Paleolithic in terms of hard, sharp stone tools and the bones of butchered animals. Through that lens, life looks very harshperhaps even harsher than it really was. Most of the human experience is missing from the archaeological record, including creature comforts like soft, clean beds. Beds were burning Until now, the oldest bedding archaeologists had ever found came from another South African site called Sibudu, where people 77,000 years ago had piled up layers of grasslike wetland plants called sedge, mixed with assorted medicinal plants, and occasionally burned the old layers. Some modern people in parts of Africa also use plants as bedding in similar ways. The Border Cave find shows that people have been making comfy sleeping pallets out of grass for at least 200,000 yearsnearly as long as there have been Homo sapiens in the world.
- This dried grass, atop a layer of ash, is around 43,000 years old.
- These fragments of silicified grass were once a layer of clean bedding, around 200,000 years ago.
Google Music shutdown starts this month, music deleted in December - Ars Technica
August begins the four-month Google Music shutdown.
Enlarge/ Please don't hurt our music collections, Google. 146 with 116 posters participating, including story author Google Play Music has been given the death sentence by Google, and today the company has announced a bit more detail about how its execution will be carried out. The main message from today's blog post is "back up your music now," as Google says it will wipe out all Google Music collections in December 2020. We've known for a while that the shutdown would be sometime in 2020, but for most regions, Google has now narrowed it down to "October." Here's the full timeline:
- Late AugustUsers will no longer be able to upload or download music through Music Manager. Pre-orders and purchases will be shut down.
- SeptemberStreaming shuts down for users in New Zealand and South Africa.
- OctoberGlobal streaming shutdown. The Google Music app and website will cease to be.
- DecemberMusic collections get deleted.
Scientists unlocked the secret of how these ultra-black fish absorb light - Ars Technica
The fish skin absorbs more than 99.5% of light thanks to pigment-packed granules
Anoplogaster cornuta. A unique arrangement of pigment-packed granules enables some fish to absorb nearly all of the light that hits their skin, so that as little as 0.05 percent of that light is reflected back."/> Enlarge/ One specimen of the ultra-black fish species Anoplogaster cornuta. A unique arrangement of pigment-packed granules enables some fish to absorb nearly all of the light that hits their skin, so that as little as 0.05 percent of that light is reflected back. 10 with 9 posters participating In the darkest depths of the ocean, where little to no light from the surface penetrates, an unusual array of creatures thrives, many of which create their own light via bioluminescence to hunt for prey, among other uses. But there are also several species of fish that have evolved the opposite survival strategy: they are ultra-black, absorbing nearly all light that strikes their skin, according to a new paper in Current Biology. Karen Osborn of the Smithsonian's Museum of Natural History became intrigued by the creatures upon finding she was unable to capture these ultrablack fish on camera while working in the field, trying to photograph specimens caught in the team's deep-sea trawl nets. "Two specimens, the Anoplogaster cornuta and the Idiacanthus antrostomus, were the only two fish over the course of six years of field work that I was able to get decent photographs of," Osborn told Ars. To do so, she used a Canon Mark II DSL R body and 65 mm macro lens with four strobes, then tested various lighting setups by taking lots and lots of photographs. Finally, she adjusted contrast and applied a high pass filter uniformly across the images, the better to bring out the details. It still wasn't sufficient to capture most of the specimens caught in the trawl net. "Over the years I deleted thousands of failed shots of other fish as useless because I couldnt bring out the details in the photos," she added. "It didn't matter how you set up the camera or lightingthey just sucked up all the light. I wish I had a few of them now to illustrate this." To discover why this was the case, Osborn teamed up with Duke University biologist Sönke Johnsen, among others, and laboratory measurements showed that, indeed, these ultra-black fish absorbed more than 99.5 percent of any light that hit their skin. That is a handy adaptation for survival in the dark depths of the sea, where even a few photons of lightsay, from hungry nearby bioluminescent organismscan give away a fish's position to a predator.
- Another angle on the ultra-black fish species Anoplogaster cornuta.
- This Anoplogaster cornuta fish was so lively after being sampled and documented that the research team released it back to the deep via submarine the day after being caught in a trawl net.
- The ultra-black Pacific blackdragon (Idiacanthus antrostomus), the second-blackest fish studied by the research team.
- The Pacific black dragon has a bioluminescent lure that they use to attract prey, and if not for their ultra-black skin and transparent, anti-reflective teeth, the reflection of their lure would scare prey away.
- The Pacific blackdragon also has light-producing organs below their eyes that scientists expect might be used as a searchlight to spot prey.
- The ultra-black ridgehead (Poromitra crassiceps). These fish are also commonly known as bigscales because of the few giant scales they possess. Their ultra-black skin covers their scales, but the skin and scales detach easily when a predator tries to grab them.
After nearly a month in space, NASA seems really happy with Crew Dragon - Ars Technica
NASA still hasn't decided whether Dragon will land in the Atlantic or Gulf of Mexico.
62 with 41 posters participating
- This image shows Dragonship Endeavour approaching the International Space Station.
- Dragon, with a Canadian robotic arm.
- Dragon coming in for its final approach.
- After the space shuttle and Russian Soyuz, Dragon is the third type of crewed vehicle to dock at the space station.
- This image of Dragon docked to the International Space Station was captured by Russian cosmonaut Ivan Vagner.
Microsoft is adding Linux, Android, and firmware protections to Windows - Ars Technica
Unfortunately, all 3 additions are currently available only to big organizations.
18 with 17 posters participating Microsoft is moving forward with its promise to extend enterprise security protections to non-Windows platforms with the general release of a Linux version and a preview of one for Android. The software maker is also beefing up Windows security protections to scan for malicious firmware. The Linux and Android movesdetailed in posts published on Tuesday here, here, and herefollow a move last year to ship antivirus protections to macOS. Microsoft disclosed the firmware feature last week. All the new protections are available to users of Microsoft Advanced Threat Protection and require Windows 10 Enterprise Edition. Public pricing from Microsoft is either non-existent or difficult to find, but according to this site, costs range from $30 to $72 per machine per year to enterprise customers. In February, when the Linux preview became available, Microsoft said it included antivirus alerts and preventive capabilities. Using a command line, admins can manage user machines, initiate and configure antivirus scans, monitor network events, and manage various threats. We are just at the beginning of our Linux journey and we are not stopping here! Tuesdays post announcing the Linux general availability said. We are committed to continuous expansion of our capabilities for Linux and will be bringing you enhancements in the coming months. The Android preview, meanwhile, provides several protections, including:
- The blocking of phishing sites and other high-risk domains and URLs accessed through SMS/text, WhatsApp, email, browsers, and other apps. The features use the same Microsoft Defender SmartScreen services that are already available for Windows so that decisions to block suspicious sites will apply across all devices on a network.
- Proactive scanning for malicious or potentially unwanted applications and files that may be downloaded to a mobile device.
- Measures to block access to network resources when devices show signs of being compromised with malicious apps or malware.
- Integration to the same Microsoft Defender Security Center thats already available for Windows, macOS, and Linux.