Mold spores commonly found aboard the International Space Station (ISS) turn out to be radiation resistant enough to survive 200 times the X-ray dose needed to kill a human being. Based on experiments by a team of researchers led by Marta Cortesão, a microbiologist at the German Aerospace Center (DLR) in Cologne, the new study indicates that sterilizing interplanetary spacecraft may be much more difficult than previously thought.
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The ISS is a collection of sealed cans inhabited by people who spend every minute of the day sweating, touching things, and exhaling moist air. Even with regular cleaning and a life support system designed to keep things under control, the result is a constant battle against mold and bacteria.
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The researchers exposed samples of Aspergillus and Pennicillium spores to X-rays, heavy ions, and high-frequency ultraviolet light of the kinds and intensities found in space. Such radiation damages DNA and breaks down cell structures, but the spores survived X-rays up to 1,000 gray, heavy ions at 500 gray, and UV rays up to 3,000 joules per meter squared.
Gray is a measurement of radiation exposure based on the absorption of one joule of radiation energy per kilogram of matter. To place the results into perspective, five gray will kill a person and 0.7 gray is how much radiation the crew of a Mars mission would receive on a 180-day mission.
Since mold spores can already survive heat, cold, chemicals, and drying out, being able to take on radiation as well poses new challenges. It means that not only will manned missions have to put a lot of effort into keeping the ship clean and healthy, it also means that unmanned planetary missions, which must be free of terrestrial organisms to prevent contaminating other worlds, will be harder to sterilize.
But according to Cortesão there is a positive side to this resiliency. Since fungal spores are hard to kill, they’d be easier to carry along and grow under controlled conditions in space, so they can be used as raw materials or act as biological factories.
“Mold can be used to produce important things, compounds like antibiotics and vitamins, says Cortesão. “It’s not only bad, a human pathogen and a food spoiler, it also can be used to produce antibiotics or other things needed on long missions.”
Since the present study only looked at radiation, orbital experiments are scheduled for later this year that will test their ability to withstand the combination of radiation, vacuum, cold, and low gravity found in space.
Launch occurred at 0630 UTC on 25 June and the side boosters of the heavy lifter were shut down and separated from the centre core approximately 2 minutes 30 seconds later. The boosters, previously used for the last Falcon Heavy launch, headed back to briefly light up Landing Zones 1 and 2 with a synchronised touchdown.
The remaining Falcon 9 first stage continued its burn for another minute before it too was shut down and separated from the second stage of the Falcon Heavy.
Unlike the side boosters, the centre core was faced with what the SpaceX PAO breathlessly described as “the most difficult landing we’ve had to date” with the spent booster coming in fast towards the drone ship Of Course I Still Love You, which was stationed twice as far into the North Atlantic Ocean (from Port Canaveral) than usual.
Not that anything involving landing the first stage of an orbital booster on its end atop a platform at sea should ever be described as something so mundane as “usual”.
SpaceX has yet to successfully recover a Falcon Heavy centre stage. The maiden launch of the rocket saw the stage undergo a rapid disassembly after its engines failed to reignite to slow the thing down. The second did land, but subsequently toppled over.
Third time was, alas, not the charm. While the engines (the centre and two extra) ignited as planned, cameras on the drone ship captured the returning first stage appearing to miss the barge before creating its own night-into-day moment with a spectacular explosion.
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And the fairing? Much whooping could be heard as SpaceX finally managed to catch one half in the net strung atop Ms Tree (pic here), the ship formerly known as Mr Steven. This was the first time the company has accomplished the feat. The other half will be recovered from the water.
According to new research, Antlia 2’s current position is consistent with a collision with the Milky Way hundreds of millions of years ago that could have produced the perturbations we see today. The paper has been submitted for publication and is undergoing peer review.
Antlia 2 was a bit of a surprise when it showed up in the second Gaia mission data release last year. It’s really close to the Milky Way – one of our satellite galaxies – and absolutely enormous, about the size of the Large Magellanic Cloud.
But it’s incredibly diffuse and faint, and hidden from view by the galactic disc, so it managed to evade detection.
That data release also showed in greater detail ripples in the Milky Way’s disc. But astronomers had known about perturbations in that region of the disc for several years by that point, even if the data wasn’t as clear as that provided by Gaia.
It was based on this earlier information that, in 2009, astrophysicist Sukanya Chakrabarti of the Rochester Institute of Technology and colleagues predicted the existence of a dwarf galaxy dominated by dark matter in pretty much the exact location Antlia 2 was found nearly a decade later.
Using the new Gaia data, the team calculated Antlia 2’s past trajectory, and ran a series of simulations. These produced not just the dwarf galaxy’s current position, but the ripples in the Milky Way’s disc by way of a collision less than a billion years ago.
Simulation of the collision: The gas distribution is on the left, stars on the right. (RIT)
Previously, a different team of researchers had attributed these perturbations to an interaction with the Sagittarius Dwarf Spheroidal Galaxy, another of the Milky Way’s satellites.
Chakrabarti and her team also ran simulations of this scenario, and found that the Sagittarius galaxy’s gravity probably isn’t strong enough to produce the effects observed by Gaia.
“Thus,” the researchers wrote in their paper, “we argue that Antlia 2 is the likely driver of the observed large perturbations in the outer gas disk of the Galaxy.”
The first batch of satellites were launched from Cape Canaveral, Florida, and deployed to orbit by a Falcon 9 rocket on May 23. Each contains a single solar array, which both captures and bounces sunlight off the satellites and, as a result, can sometimes be seen from Earth. On May 25, as the drifting luminescent army of satellites zoomed overhead, Dutch satellite tracker Marco Langbroek captured their marching, posting a stunning video to Vimeo.
In time, the satellites will drift apart and head to specific orbits so that satellite internet coverage can be beamed to every corner of the globe.
However, as the unusual display in the night sky quickly gathered steam across social media, some astronomers began to point out the potential problems the satellite system may pose for astronomy. At present, only 60 satellites are moving into their orbit, but eventually that number will reach 12,000, and a megaconstellation will encircle the Earth. Practically overnight, our view of the sky has changed.
“We’ve become used to change in space activities as slow and incremental, and suddenly, it’s fast and speeding up,” said Alice Gorman, space archeologist at Flinders University, Australia. “By its very visibility, Starlink has opened up some big questions: who gets to use Earth orbit and what for?”
Watch this: SpaceX launches first batch of Starlink satellites
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Indeed, Starlink would triple the number of satellites orbiting the Earth. If thousands of satellites are sent into orbit, our view of space changes. Will we find ourselves in a position where it’s impossible to investigate the cosmos from the ground?
The quick answer: not forever, no. SpaceX designed the Starlink satellites to fall back to the Earth after about five years of service..
“The satellites are meant to put themselves in a re-entry orbit at the end of their mission life, and remove themselves from the debris population by burning up,” says Gorman.
But the long answer is: potentially. Astronomers already wrangle with the problems posed by space robots and satellites circling the Earth whenever they turn their ground-based telescopes toward the stars. Bright, reflective surfaces pose a problem because they obstruct our view of the universe.
More satellites equals cloudier vision, and Starlink plans to launch more satellites than ever.
When the sun is reflecting off the satellites’ solar panels, astronomers will have to account for the appearance of the satellites in their images. SpaceX was relatively mum about the design of the satellites leading up to launch, so it’s come as a bit of a surprise to some astronomers just how bright they are. However, the satellites will position their solar panels as they establish themselves in orbit, which should reduce their brightness.
Jonathan McDowell, an astronomer with the Harvard-Smithsonian Center for Astrophysics, perhaps summed it up best in a tweet, saying the satellites are “brighter than we had expected and still a problem, but somewhat less of a sky-is-on-fire problem.”
“Somewhat less of a sky-is-on-fire problem” sounds slightly reassuring, at least. But there do seem to be clear issues for the astronomy community..
Elon Musk, SpaceX CEO, jumped to the defense of his satellite system and noted on Twitter how “potentially helping billions of economically disadvantaged people is the greater good,” while making it clear that SpaceX plans to limit Starlink’s effects on astronomy. “We care a great deal about science,” Musk tweeted. He said he’s sent a note to the Starlink team to reduce albedo — that is, the amount of light the satellites reflect.
In addition, after a user suggested placing space telescopes using Starlink chassis into orbit to appease the astronomers, Musk said he “would love to do exactly that.” That might ease concerns, but will it slow our quickening colonization of Earth’s orbit? Unlikely.
“Space agencies and organizations have been cluttering the sky for decades and taking a very lax attitude to the long-term consequences,” said Gorman.
With a number of satellite constellations on the way, it will be critical for regulatory bodies and satellite providers to adequately manage the space debris and satellite problem, lest all of our space robots collide and lock us on Earth forever (yes, that’s a faint but possible catastrophic scenario)
A recent parachute test of the SpaceX Crew Dragon capsule “was not satisfactory,” a NASA official said during a House subcommittee hearing yesterday. Few details were disclosed, but it’s now looking even less likely that NASA will have the capability to fly astronauts to space anytime soon.
The House Science, Space, and Technology Committee held a hearing in Washington, DC, yesterday to discuss NASA’s plans to go to the Moon, and how the accelerated lunar timeline might affect the larger goal of sending humans to Mars. During the meeting, however, the conversation turned to a previously undisclosed incident that happened last month at Nevada’s Delamar Dry Lake during a test of the SpaceX Crew Dragon parachute system.
“The test was not satisfactory,” replied Bill Gerstenmaier, NASA Associate Administrator for Human Exploration and Operations, in response to a question posed by Alabama Congressman Morris Brooks. “We did not get the results we wanted, but we learned some information that’s going to affect, potentially, future parachute designs,” said Gerstenmaier.
When asked what he meant by unwanted results, the NASA official said the testing apparatus was “damaged upon impact with the ground.”
In an email to Gizmodo, a SpaceX spokesperson confirmed the incident, saying it was an “advanced development test” designed to measure the stresses endured by the parachutes. Rather than use an actual Crew Dragon capsule, however, SpaceX used a simple metal test sled. During the test, the parachutes didn’t fully open and the sled hit the ground at “a higher than expected velocity,” according to the spokesperson, adding that no one was hurt and no property damage occurred at the test site.
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As to the cause of the failure, Gerstenmaier was unable to provide an answer.
“We still need to understand whether it was a test setup configuration coming out of the aircraft or if there was something associated with the packing of the parachute, the rigging, all that,” he told the Committee. During the failed test, the loads within each parachute canopy were recorded, and this data will be used during the investigation, he said.
Japan can finally include itself among the ranks of countries with successful private spaceflight outfits. Interstellar Technologies has successfully launched its MOMO-3 sounding rocket into space, with the vehicle easily crossing the Kármán line (62 miles in altitude) before splashing into the Pacific. It’s a modest start — the rocket only stayed aloft for 8 minutes and 35 seconds — but it’s also a relief after Interstellar’s previous two attempts ended in failure.
There was a fair amount riding on the mission. Interstellar’s ultimate aim is to ferry small satellites into orbit at a fraction of the cost of government launches, and this takes the company one step closer to achieving its dream. It also relieves some of the pressure on Interstellar founder Takafumi Horie. There had been skepticism about the Livedoor creator’s spaceflight chops given his controversial entrepreneurial history (including a conviction for accounting fraud). This shows that his initiative can work on a basic level — the challenge is translating a test like this into a full-fledged business.
The space agency eggheads pointed the finger of blame at the aluminium manufacturer after probing two failed science missions: the February 24, 2009 fruitless launch of the Orbiting Carbon Observatory, and the March 4, 2011 doomed launch of the Glory satellite, designed for monitoring atmospheric pollutants.
In both cases, the rocket fairing, which is the nose cone protecting the satellite payload, failed to separate after liftoff. As a result, the Orbiting Carbon Observatory (OCO) plunged into the ocean off the Antarctic, and Glory swiftly crashed into the Pacific, after their rockets fell back to Earth, the satellites still attached.
The blunders were traced back to the fairing release mechanism, and specifically the aluminium (or aluminum in Freedom Language) used in this component. It was supplied by Sapa Profiles Inc, of Oregon, USA, now renamed Hydro Extrusion Portland, Inc. NASA’s boffins said the metals used were not up to specification, and called in the Feds.
Subsequent checks appeared to show that Sapa had been falsifying its materials testing reports for profit. The metal was supposed to have a particular tensile strength, however, company employees fudged the tests to increase profit margins, investigators said.
After weeks of speculation, SpaceX has finally admitted that a Crew Dragon capsule was destroyed during a test of system’s abort thrusters on April 20. No cause was given for the anomaly, nor were any new details disclosed about possible delays to NASA’s languishing Commercial Crew Program.
Speaking to reporters at a NASA briefing held earlier this week, Hans Koenigsmann, the vice president of build and flight reliability at SpaceX, said the mishap is “certainly not great news,” in terms of the company’s plan to launch astronauts into space later this year, as CBS News reports. The purpose of the briefing was to discuss an upcoming cargo launch to the ISS, but the incident, in which a Crew Dragon capsule got torched just prior to the firing of launch-abort thrusters, dominated much of the discussion.
The mishap occurred at Cape Canaveral’s Landing Zone 1 on April 20 during static ground tests of the system’s boosters. The Crew Dragon was reportedly engulfed in flames and thick orange-black smoke, which was probably toxic, could be seen for miles. Both NASA and SpaceX have been tight-lipped about the incident, but Koenigsmann shared some new information with reporters during the briefing.
Tests of the system’s smaller, maneuvering Draco thrusters were done earlier in the day without incident, he said. It was when the focus shifted to the system’s larger SuperDraco boosters—a series of eight thrusters tied to the abort system—that things went sideways.
“At the test stand, we powered up Dragon, it powered up as expected, we completed tests with the Draco thrusters—the smaller thrusters that are also on the cargo Dragon,” said Koenigsmann per CBS News. “And then just before we wanted to fire the SuperDracos there was an anomaly and the vehicle was destroyed.”
On the afternoon of December 3rd, 2018, a SpaceX Falcon 9 rocket took off from the southern coast of California, lofting the largest haul of individual satellites the vehicle had ever transported. At the time, it seemed like the mission was a slam dunk, with all 64 satellites deploying into space as designed.
But nearly four months later, more than a dozen satellites from the launch have yet to be identified in space. We know that they’re up there, and where they are, but it’s unclear which satellites belong to which satellite operator on the ground.
They are, truly, unidentified flying objects.
The launch, called the SSO-A SmallSat Express, sent those small satellites into orbit for various countries, commercial companies, schools, and research organizations. Currently, all of the satellites are being tracked by the US Air Force’s Space Surveillance Network — an array of telescopes and radars throughout the globe responsible for keeping tabs on as many objects in orbit as possible. Yet 19 of those satellites are still unidentified in the Air Force’s orbital catalog. Many of the satellite operators do not know which of these 19 probes are theirs exactly, and the Air Force can’t figure it out either.
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Not knowing the exact location of a spacecraft is a major problem for operators. If they can’t communicate with their satellite, the company’s orbiting hardware becomes, essentially, space junk. It brings up liability and transparency concerns, too. If an unidentified satellite runs into something else in space, it’s hard to know who is to blame, making space less safe — and less understood — for everyone. That’s why analysts and space trackers say both technical and regulatory changes need to be made to our current tracking system so that we know who owns every satellite that’s speeding around the Earth. “The whole way we do things is just no longer up to the task,” Jonathan McDowell, an astrophysicist at Harvard and spaceflight tracker, tells The Verge.
How to identify a satellite
Up until recently, figuring out a satellite’s identity has been relatively straightforward. The Air Force has satellites high above the Earth that detect the heat of rocket engines igniting on the ground, indicating when a vehicle has taken off. It’s a system that was originally put in place to locate the launch of a potential missile, but it’s also worked well for spotting rockets launching to orbit. And for most of spaceflight history, usually just one large satellite or spacecraft has gone up on a launch — simplifying the identification process.
“For more traditional launches, where there are fewer objects, it’s fairly simple to do,” Diana McKissock, the lead for space situational awareness sharing and spaceflight safety at the Air Force’s 18th Space Control Squadron, tells The Verge. As a result, the Air Force has maintained a robust catalog of more than 20,000 space objects in orbit, many of which have been identified.
But as rocket ride-shares have grown in popularity, the Air Force’s surveillance capabilities have sometimes struggled to identify every satellite that is deployed during a launch. One problem is that most of the spacecraft on board all look the same. Nearly 50 satellites on the SSO-A launch were modified CubeSats — a type of standardized satellite that’s roughly the size of a cereal box. That means they are all about the same size and have the same general boxy shape. Plus, these tiny satellites are often deployed relatively close together on ride-share launches, one right after the other. The result is a big swarm of nearly identical spacecraft that are difficult to tell apart from the ground below.
Operators often rely on tracking data from the Air Force to find their satellites, so if the military cannot tell a significant fraction of these CubeSats apart, the operators don’t know where to point their ground communication equipment to get in contact with their spacecraft.
It’s a bit of a Catch-22, though. The Air Force also relies on satellite operators to help identify their spacecraft. Before a launch, the Air Force collects information from satellite operators about the design of the spacecraft and where it’s going to go. The operators are also responsible for making sure that they have the proper equipment (in space and on the ground) to communicate with the satellite. “It’s really a cooperative, ongoing process that involves the satellite operators as much as it involves us here at the 18th, processing the data,” says McKissock.
The SSO-A launch isn’t the only example of mistaken satellite identity. Five satellites are still unidentified from an Electron launch that took place in December last year, which sent up 13 objects, according to McDowell. And in 2017, a Russian Soyuz rocket deployed a total of 72 satellites, but eight are still unknown, says McDowell. The SSO-A launch is perhaps the most egregious example of this ride-share problem, as nearly a third of the satellites are still missing in the Air Force’s catalog.
The Air Force says the launch posed a unique challenge. One difficulty had to do with the way the satellites were deployed, according to McKissock, who says it was hard to predict before the launch where each satellite was going to be. The SSO-A launch was organized by a company called Spaceflight Industries, which acts as a broker for operators — finding room for their satellites on upcoming rocket launches. Spaceflight bought this entire Falcon 9 rocket for the SSO-A launch, and created the device that deployed all of these satellites into orbit. One satellite tracker, T.S. Kelso, who operates a tracking site called CelesTrak, agreed with the Air Force, saying that Spaceflight’s deployment platform made it hard to predict each satellite’s exact position. “[Spaceflight] had no way to provide the type of data needed,” Kelso writes in an email to The Verge.
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The Air Force’s 18th Space Control Squadron has other priorities to consider, too. While identifying spacecraft is something the team always hopes to accomplish on every flight, the main function of the 18th is to track as many objects as possible and then provide information on the possibility of spacecraft running into each other in orbit. The identification of satellites is secondary to that safety concern. “I wouldn’t say it’s not a priority, but we certainly have other mission requirements to consider,” says McKissock.
India launched a missile at a satellite believed to be the Indian spy satellite Microsat-r, launched a few months ago. The blowup created a field of satellite debris at that altitude. That debris is a problem because it sits at the same altitude as the ISS. In a worst-case scenario, some of that debris could impact the station creating a Gravity-esque scenario. Some of those pieces are too small for NASA to track, meaning we’ll have no way of predicting an impact beforehand.
“What we are tracking right now, objects big enough to track — we’re talking about 10 cm (4 inches) or bigger —about 60 pieces have been tracked,” Bridenstine said in an announcement on Monday.
India deliberately targeted a satellite that orbited at a lower altitude than the ISS to prevent this sort of situation, but some of the debris appears to have reached higher. Of those 60 debris objects tracked by NASA, Bridenstine says 24 of them are at the same altitude as the ISS or higher.
The nature of low Earth orbit means that even debris pieces residing above the ISS could still pose a threat. Satellites and debris are gradually slowed by the very thin atmosphere that resides there. The ISS, for instance, routinely has to fire its boosters to increase its altitude to counteract atmospheric drag.
Those small debris pieces will lose altitude over time and eventually burn up in the atmosphere, but the high-altitude debris will have to come in range of the ISS before that happens. That means an impact could happen even a few months from now as high-altitude debris continues to fall.
The head of the United States’ National Aeronautics and Space Administration (NASA), Jim Bridenstine, on Tuesday branded India’s destruction of one of its satellites a “terrible thing” that had created 400 pieces of orbital debris and led to new dangers for astronauts aboard the International Space Station (ISS).
Mr. Bridenstine was addressing employees of the NASA five days after India shot down a low-orbiting satellite in a missile test to prove it was among the world’s advanced space powers.
Not all of the pieces were big enough to track, Mr. Bridenstine explained. “What we are tracking right now, objects big enough to track — we’re talking about 10 cm [six inches] or bigger — about 60 pieces have been tracked.”
The Indian satellite was destroyed at a relatively low altitude of 300 km, well below the ISS and most satellites in orbit.
But 24 of the pieces “are going above the apogee of the ISS,” said Mr. Bridenstine.
“That is a terrible, terrible thing to create an event that sends debris at an apogee that goes above the International Space Station. That kind of activity is not compatible with the future of human spaceflight. It’s unacceptable and NASA needs to be very clear about what its impact to us is,” he said.
But the risk will dissipate over time as much of the debris will burn up as it enters the atmosphere.
The U.S. military tracks objects in space to predict the collision risk of the ISS and satellites.
They are currently tracking 23,000 objects larger than 10 cm.
Chinese test created 3,000 debris
That includes about 10,000 pieces of space debris, of which nearly 3,000 were created by a single event: a Chinese anti-satellite test in 2007 at 530 miles from the surface.
As a result of the Indian test, the risk of collision with the ISS has increased by 44 percent over 10 days, Mr. Bridenstine said.
Soon after the ASAT test, India said it was done in the lower atmosphere to ensure that there is no space debris. “Whatever debris that is generated will decay and fall back onto the earth within weeks.”
By conducting the test, the Ministry of External Affairs in New Delhi said, India was not in violation of any international law or treaty to which it is a party to or any national obligation.
Interestingly, Bridenstine is the first top official from the Trump administration to come out in public against the India’s ASAT test.
A day after India successfully carried out its ASAT test, acting US defence secretary Patrick Shanahan warned that the event could create a “mess” in space but said Washington was still studying the impact.
Bridenstine said the NASA is “learning more and more every hour” that goes by about this orbital debris field that has been created from the anti-satellite test.
“Where we were last week with an assessment that comes from NASA experts as well as the Joint Space Operations Center (part of US Strategic Command).. is that the risk to the International Space Station has increased by 44 per cent,” Bridenstine said.
“We are charged with commercialising of low earth orbit. We are charged with enabling more activities in space than we’ve ever seen before for the purpose of benefiting the human condition, whether it’s pharmaceuticals or printing human organs in 3D to save lives here on earth or manufacturing capabilities in space that you’re not able to do in a gravity well,” he said.
“All of those are placed at risk when these kinds of events happen,” Bridenstine said as he feared India’s ASAT test could risk proliferation of such activities by other countries.
“When one country does it, other countries feel like they have to do it as well,” he said.
“It’s unacceptable. The NASA needs to be very clear about what its impact to us is,” he said.
Risk gone up 44% over 10 days
The risk from small debris as a result of the ASAT test to the ISS went up 44 per cent over a period of 10 days. “So, the good thing is it’s low enough in earth orbit that over time this will all dissipate,” he told his NASA colleagues.
The ISS is a habitable artificial satellite, orbiting the Earth at an altitude between 330 and 435 km. It is a joint project between space agencies of US, Russia, Japan, Europe and Canada, and serves as a research laboratory for scientists to conduct space experiments.
As many as 236 astronauts from 18 countries have visited the space station, many of them multiple times, since November 2000.
Bridenstine said a lot of debris from the 2007 direct ascent anti-satellite test by China is still in the space.
“And we’re still dealing with it. We are still, we as a nation are responsible for doing space situational awareness and space traffic management, conjunction analysis for the entire world,” the NASA chief said.
“The International Space Station is still safe. If we need to manoeuvre it, we will. The probability of that I think is low. But at the end of the day we have to be clear also that these activities are not sustainable or compatible with human spaceflight,” he said.
Most people think that the Earth’s atmosphere stops a bit over 62 miles (100 km) from the surface, but a new study based on observations made over two decades ago by the joint US-European Solar and Heliospheric Observatory (SOHO) satellite shows that it actually extends as far 391,000 miles (630,000 km) or 50 times the Earth’s diameter. This makes the Moon a very high altitude aircraft.
If you’re living in Earth’s southern hemisphere, chances are you may be able to see some of the stars in a newly identified cosmic river that’s flowed through the Milky Way for hundreds of millions of years.
Astronomers say the freshly discovered gigantic cluster of stars is passing relatively close to our Solar System. The cluster contains at least 4,000 stars that have been steadily moving together across the night sky like a river, covering almost the entire southern sky. To be clear, the stars aren’t new discoveries: the fact they are in a cluster together is the revelation here.
“Most star clusters in the galactic disk disperse rapidly after their birth as they do not contain enough stars to create a deep gravitational potential well, or in other words, they do not have enough glue to keep them together,” said Stefan Meingast, lead author of the study published today in Astronomy & Astrophysics journal and an astronomer working at the University Vienna, Austria.
If you’re living in Earth’s southern hemisphere, chances are you may be able to see some of the stars in a newly identified cosmic river that’s flowed through the Milky Way for hundreds of millions of years.
Astronomers say the freshly discovered gigantic cluster of stars is passing relatively close to our Solar System. The cluster contains at least 4,000 stars that have been steadily moving together across the night sky like a river, covering almost the entire southern sky. To be clear, the stars aren’t new discoveries: the fact they are in a cluster together is the revelation here.
“Most star clusters in the galactic disk disperse rapidly after their birth as they do not contain enough stars to create a deep gravitational potential well, or in other words, they do not have enough glue to keep them together,” said Stefan Meingast, lead author of the study published today in Astronomy & Astrophysics journal and an astronomer working at the University Vienna, Austria.
“Even in the immediate solar neighborhood, there are, however, a few clusters with sufficient stellar mass to remain bound for several hundred million years. So, in principle, similar, large, stream-like remnants of clusters or associations should also be part of the Milky Way disk.”
It is estimated the stellar river formed about a billion years ago, and has circled the Milky Way four times already.
The projection of the stellar stream centered around the south Galactic pole. The Milky Way is curved around in an arc, and the red points are the stars in the cluster. Image credit: Astronomy & Astrophsyics.
The researchers from the University of Vienna and Harvard University spotted the stellar stream by carefully mapping the 3D motion of 200 stars using data taken from Europe’s Gaia spacecraft. The stars’ distribution and movements showed telltale signs that they were all locked in a clump together, and are being pulled apart by the Milky Way’s gravitational field.
“Identifying nearby disk streams is like looking for the proverbial needle in a haystack,” said João Alves, co-author of the paper and an astrophysics professor at the University of Vienna.
“Astronomers have been looking at, and through, this new stream for a long time, as it covers most of the night sky, but only now realize it is there, and it is huge, and shockingly close to the Sun. Finding things close to home is very useful, it means they are not too faint nor too blurred for further detailed exploration, as astronomers dream.”
The Sloan Digital Sky Survey has created the most detailed three-dimensional maps of the Universe ever made, with deep multi-color images of one third of the sky, and spectra for more than three million astronomical objects
The Milky Way galaxy’s disk of stars is anything but stable and flat. Instead, it becomes increasingly warped and twisted far away from the Milky Way’s center, according to astronomers from National Astronomical Observatories of Chinese Academy of Sciences (NAOC).
From a great distance, the galaxy would look like a thin disk of stars that orbit once every few hundred million years around its central region, where hundreds of billions of stars, together with a huge mass of dark matter, provide the gravitational ‘glue’ to hold it all together.
But the pull of gravity becomes weaker far away from the Milky Way’s inner regions. In the galaxy’s far outer disk, the hydrogen atoms making up most of the Milky Way’s gas disk are no longer confined to a thin plane, but they give the disk an S-like warped appearance.
“It is notoriously difficult to determine distances from the sun to parts of the Milky Way’s outer gas disk without having a clear idea of what that disk actually looks like,” says Dr. Chen Xiaodian, a researcher at NAOC and lead author of the article published in Nature Astronomy on Feb. 4.
“However, we recently published a new catalogue of well-behaved variable stars known as classical Cepheids, for which distances as accurate as 3 to 5 percent can be determined.” That database allowed the team to develop the first accurate three-dimensional picture of the Milky Way out to its far outer regions.
Top: 3D distribution of the classical Cepheids in the Milky Way’s warped disk. Bottom: Precession of the warp’s line of nodes with Galactocentric radius. Credit: CHEN Xiaodian
Classical Cepheids are young stars that are some four to 20 times as massive as the sun and up to 100,000 times as bright. Such high stellar masses imply that they live fast and die young, burning through their nuclear fuel very quickly, sometimes in only a few million years. They show day- to month-long pulsations, which are observed as changes in their brightness. Combined with a Cepheid’s observed brightness, its pulsation period can be used to obtain a highly reliable distance.
“Somewhat to our surprise, we found that in 3-D, our collection of 1339 Cepheid stars and the Milky Way’s gas disk follow each other closely. This offers new insights into the formation of our home galaxy,” says Prof. Richard de Grijs from Macquarie University in Sydney, Australia, and senior co-author of the paper. “Perhaps more importantly, in the Milky Way’s outer regions, we found that the S-like stellar disk is warped in a progressively twisted spiral pattern.”
A rocket carrying a satellite on a mission to deliver the world’s first artificial meteor shower blasted into space on Friday, Japanese scientists said.
A start-up based in Tokyo developed the micro-satellite for the celestial show over Hiroshima early next year as the initial experiment for what it calls a “shooting stars on demand” service.
The satellite is to release tiny balls that glow brightly as they hurtle through the atmosphere, simulating a meteor shower.
It hitched a ride on the small-size Epsilon-4 rocket that was launched from the Uchinoura space centre by the Japan Aerospace Exploration Agency (JAXA) on Friday morning.
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The company ALE Co. Ltd plans to deliver its first out-of-this-world show over Hiroshima in the spring of 2020.
Lena Okajima, CEO of a space technology venture ALE is hoping to deliver shooting stars on demand and choreograph the cosmos
The satellite launched Friday carries 400 tiny balls whose chemical formula is a closely-guarded secret.
That should be enough for 20-30 events, as one shower will involve up to 20 stars, according to the company.
ALE’s satellite, released 500 kilometres (310 miles) above the Earth, will gradually descend to 400 kilometres over the coming year as it orbits the Earth.
Worldwide meteor shower shows
The company plans to launch a second satellite on a private-sector rocket in mid-2019.
ALE says it is targeting “the whole world” with its products and plans to build a stockpile of shooting stars in space that can be delivered across the world.
The annual Perseid meteor shower—seen here over eastern France—is a highlight for sky-watchers
When its two satellites are in orbit, they can be used separately or in tandem, and will be programmed to eject the balls at the right location, speed and direction to put on a show for viewers on the ground.
Tinkering with the ingredients in the balls should mean that it is possible to change the colours they glow, offering the possibility of a multi-coloured flotilla of shooting stars.
A small green shoot is growing on the moon in an out-of-this-world first after a cotton seed germinated on board a Chinese lunar lander, scientists said Tuesday.
The sprout has emerged from a lattice-like structure inside a canister since the Chang’e-4 lander set down earlier this month, according to a series of photos released by the Advanced Technology Research Institute at Chongqing University.
“This is the first time humans have done biological growth experiments on the lunar surface,” said Xie Gengxin, who led the design of the experiment.
The Chang’e-4 probe—named after a Chinese moon goddess—made the world’s first soft landing on the moon’s “dark side” on January 3, a major step in China’s ambitions to become a space superpower.
Scientists from Chongqing University —who designed the “mini lunar biosphere” experiment—sent an 18-centimetre (seven-inch) bucket-like container holding air, water and soil.
Inside are cotton, potato, and arabidopsis seeds—a plant of the mustard family—as well as fruit fly eggs and yeast.
Images sent back by the probe show a cotton sprout has grown well, but so far none of the other plants has taken, the university said.
Swarm Technologies Inc will pay a $900,000 fine for launching and operating four small experimental communications satellites that risked “satellite collisions” and threatened “critical commercial and government satellite operations,” the Federal Communications Commission said on Thursday.
The Federal Communications Commission (FCC) logo is seen before the FCC Net Neutrality hearing in Washington February 26, 2015. REUTERS/Yuri Gripas
The California-based start-up founded by former Google and Apple engineers in 2016 also agreed to enhanced FCC oversight and a requirement of pre-launch notices to the FCC for three years.
Swarm launched the satellites in India last January after the FCC rejected its application to deploy and operate them, citing concerns about the company’s tracking ability.
It said Swarm had unlawfully transmitted signals between earth stations in the state of Georgia and the satellites for over a week. The investigation also found that Swarm performed unauthorized weather balloon-to-ground station tests and other unauthorized equipment tests prior to the satellites’ launch.
Swarm aims to provide low-cost space-based internet service and plans eventually to use a constellation of 100 satellites.
Swarm won permission in August from the FCC to reactivate the satellites and said then it is “fully committed to complying with all regulations and has been working closely with the FCC,” noting that its satellites are “100 percent trackable.”
For the first time, an object in our solar system has been found more than 100 times farther than Earth is from the sun.
The International Astronomical Union’s Minor Planet Center announced the discovery Monday, calling the object 2018 VG18. But the researchers who found it are calling it “Farout.”
They believe the spherical object is a dwarf planet more than 310 miles in diameter, with a pinkish hue. That color has been associated with objects that are rich in ice, and given its distance from the sun, that isn’t hard to believe. Its slow orbit probably takes more than 1,000 years to make one trip around the sun, the researchers said.
The distance between the Earth and the sun is an AU, or astronomical unit — the equivalent of about 93 million miles. Farout is 120 AU from the sun. Eris, the next most distant object known, is 96 AU from the sun. For reference, Pluto is 34 AU away.
The object was found by the Carnegie Institution for Science’s Scott S. Sheppard, the University of Hawaii’s David Tholen and Northern Arizona University’s Chad Trujillo — and it’s not their first discovery.
The team has been searching for a super-Earth-size planet on the edge of our solar system, known as Planet Nine or Planet X, since 2014. They first suggested the existence of this possible planet in 2014 after finding “Biden” at 84 AU. Along the way, they have discovered more distant solar system objects suggesting that the gravity of something massive is influencing their orbit.
Virgin Galactic completed its longest rocket-powered flight ever on Thursday, taking a step ahead in the nascent business of space tourism.
The two pilots on board Virgin Galactic’s spacecraft Unity became the company’s first astronauts. Virgin Group founder Richard Branson was on hand to watch the historic moment.
“Many of you will know how important the dream of space travel is to me personally. Ever since I watched the moon landings as a child I have looked up to the skies with wonder,” Branson said after the flight. “This is a momentous day and I could not be more proud of our teams who together have opened a new chapter of space exploration.”
Virgin Galactic said the test flight reached an altitude of 51.4 miles, or nearly 83 kilometers. The U.S. military and NASA consider pilots who have flown above 80 kilometers to be astronauts. The Federal Aviation Administration announced on Thursday that pilots Mark Stucky and C.J Sturckow would receive commercial astronaut wings at a ceremony in Washington, D.C. early next year.
Lifted by the jet-powered mothership Eve, the spacecraft Unity took off from the Mojave Air and Space Port in the California desert. Upon reaching an altitude above 40,000 feet, the carrier aircraft released Unity. The two-member crew then piloted the spacecraft in a roaring burn which lasted 60 seconds. The flight pushed Unity to a speed of Mach 2.9, nearly three times the speed of sound, as it screamed into a climb toward the edge of space.
After performing a slow backflip in microgravity, Unity turned and glided back to land at Mojave. This was the company’s fourth rocket-powered flight of its test program.
Unity is the name of the spacecraft built by The Spaceship Company, which Branson also owns. This rocket design is officially known as SpaceShipTwo (SS2).
Unity also carried four NASA-funded payloads on this mission. The agency said the four technology experiments “will collect valuable data needed to mature the technologies for use on future missions.”
“Inexpensive access to suborbital space greatly benefits the technology research and broader spaceflight communities,” said Ryan Dibley, NASA’s flight opportunities campaign manager, in a statement.
The spacecraft underwent extensive engine testing and seven glide tests before Virgin Galactic said it was ready for a powered test flight — a crucial milestone before the company begins sending tourists to the edge of the atmosphere. Each of the previous three test flights were successful in pushing the spacecraft’s limits farther.
Yes, it can be done without rockets exploding all over the place or going the wrong direction. Well done, this is how commercial space flight should look.
NASA’s mission to send a probe to an asteroid, dig up a chunk, and send the material back to Earth is now half-way complete. The agency says its OSIRIS-REx spacecraft has reached its hunk-of-rock target after a trip lasting two years and two billion miles.
The spacecraft, technically the Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer (OSIRIS-REx) is orbiting the asteroid Bennu, a diamond-shaped chunk of space rock with a varying orbit that keeps it around 100 million miles (160 million kilometers) from Earth.
“Initial data from the approach phase show this object to have exceptional scientific value,” said Dante Lauretta, the mission’s principal investigator. “We can’t wait to get to work studying and characterizing Bennu’s rough and rugged surface to find out where the right spot is to collect the sample and bring it back to Earth.”
“Today has been very exciting, but the true nail-biting moment will be the sample collection. The best times are ahead of us, so stay tuned. The exploration of Bennu has just begun, and we have a lifetime of adventure ahead of us.”
Bennu is thought to be a lump of rock from the earliest days of the Solar System. After a couple of flybys, OSIRIS-REx will settle into a steady orbit a few miles above the surface. It will spend the next 505 days circling the asteroid and scanning it with cameras, LIDAR and spectrographs to try and find out as much information as possible about its composition.
The asteroid is of particular interest to NASA because it may contain water and clays from the protoplasmic disc that formed the Sun and the planets in our Solar System. So, once it has picked the likeliest spot and safest place to find some of these materials, the spacecraft will extend the Touch-And-Go Sample Acquisition Mechanism (TAGSAM) – a 3.35-meter (11 ft) robotic arm – and grab a handful of matter from the surface.
Once that’s done, and assuming OSIRIS-REx doesn’t hit the surface, the spacecraft will begin the long voyage back to Earth. It’s expected to arrive on September 2023 and the sealed sample contained will reenter the atmosphere using a heat shield and float back to scientists via parachute into the Utah desert.
Early in the New Year, if all goes well, the Chinese spacecraft Chang’e-4 will arrive where no craft has been before: the far side of the Moon. The mission is scheduled to launch from Xichang Satellite Launch Centre in Sichuan province on December 8. The craft, comprising a lander and a rover, will then enter the Moon’s orbit, before touching down on the surface.
If the landing is successful, the mission’s main job will be to investigate this side of the lunar surface, which is peppered with many small craters. The lander will also conduct the first radio astronomy experiments from the far side of the Moon—and the first investigations to see whether plants will grow in the low-gravity lunar environment.
A small rocket from a little-known company lifted off Sunday from the east coast of New Zealand, carrying a clutch of tiny satellites. That modest event — the first commercial launch by a U.S.-New Zealand company known as Rocket Lab — could mark the beginning of a new era in the space business, where countless small rockets pop off from spaceports around the world. This miniaturization of rockets and spacecraft places outer space within reach of a broader swath of the economy.
The rocket, called the Electron, is a mere sliver compared to the giant rockets that Elon Musk, of SpaceX, and Jeffrey P. Bezos, of Blue Origin, envisage using to send people into the solar system. It is just 56 feet tall and can carry only 500 pounds into space.
But Rocket Lab is aiming for markets closer to home.
“We’re FedEx,” said Peter Beck, the New Zealand-born founder and chief executive of Rocket Lab. “We’re a little man that delivers a parcel to your door.”
Behind Rocket Lab, a host of start-up companies are also jockeying to provide transportation to space for a growing number of small satellites. The payloads include constellations of telecommunications satellites that would provide the world with ubiquitous internet access.
The payload of this mission, which Rocket Lab whimsically named “It’s Business Time,” offered a glimpse of this future: two ship-tracking satellites for Spire Global; a small climate- and environment-monitoring satellite for GeoOptics; a small probe built by high school students in Irvine, Calif., and a demonstration version of a drag sail that would pull defunct satellites out of orbit.
Space Angels, a space-business investment firm, is tracking 150 small launch companies. Chad Anderson, Space Angel’s chief executive, said that although the vast majority of these companies will fail, a small group possess the financing and engineering wherewithal to get off the ground.
Each company on Mr. Anderson’s list proffers its own twist in business plan or capability:
Vector Launch Inc. aims for mass production;
Virgin Orbit, a piece of Richard Branson’s business empire, will drop its rockets from the bottom of a 747 at 35,000 feet up;
Relativity Space plans to 3-D print almost all pieces of its rockets;
Firefly Aerospace will offer a slightly larger rocket in a bet that the small satellites will grow a bit in size and weight;
Gilmour Space Technologies is a rare Australian aerospace company;
And Astra Space Inc., which is operating in stealth mode like a Silicon Valley start-up, saying nothing about what is doing.
Daniel Bryce, a manufactering operations manager working on a satellite at Spire Global in Glasgow.CreditAndy Buchanan/Agence France-Presse — Getty Images
Rockets are shrinking, because satellites are shrinking.
In the past, hulking telecommunications satellites hovered 22,000 miles above the Equator in what is known as a geosynchronous orbit, where a satellite continuously remains over the same spot on Earth. Because sending a satellite, there was so expensive, it made sense to pack as much as possible into each one.
Advances in technology and computer chips have enabled smaller satellites to perform the same tasks as their predecessors. And constellations of hundreds or thousands of small satellites, orbiting at lower altitudes that are easier to reach, can mimic the capabilities once possible only from a fixed geosynchronous position.
“It’s really a shift in the market,” Mr. Beck said. “What once took the size of a car is now the size of a microwave oven, and with exactly the same kind of capabilities.”
Some companies already have launched swarms of satellites to make observations of Earth. Next up are the promised space-based internet systems such as OneWeb and SpaceX’s Starlink.
Until now, such small spacecraft typically hitched a rocket ride alongside a larger satellite. That trip is cheaper but inconvenient, because the schedule is set by the main customer. If the big satellite is delayed, the smaller ones stay on the ground, too. “You just can’t go to business like that,” Mr. Beck said.
The Electron, Mr. Beck said, is capable of lifting more than 60 percent of the spacecraft that headed to orbit last year. By contrast, space analysts wonder how much of a market exists for a behemoth like SpaceX’s Falcon Heavy, which had its first spectacular launch in February.
A Falcon Heavy can lift a payload 300 times heavier than a Rocket Lab Electron, but it costs $90 million compared to the Electron’s $5 million. Whereas SpaceX’s standard Falcon 9 rocket has no shortage of customers, the Heavy has only announced a half-dozen customers for the years to come.
The United States military — a primary customer for large launch vehicles — is also rethinking its spy satellites. The system would be more resilient, some analysts think, if its capabilities were spread among many, smaller satellites. Smaller satellites would be easier and quicker to replace, and an enemy would have a harder time destroying all of them.
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The Rocket Lab production facility. Its rockets cost $5 million.CreditRocket Lab
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A Rocket Lab Rutherford engine test.CreditRocket Lab
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An Electron “Still Testing” rocket with Shaun D’Mello, Rocket Lab’s vice president of launch.CreditRocket Lab
Pit stops in the space race
SpaceX could have cornered this market a decade ago.
Its first rocket, the Falcon 1, was designed to lift about 1,500 pounds. But after just two successful launches, SpaceX abandoned it, focusing on the much larger Falcon 9 to serve NASA’s needs to carry cargo and, eventually, astronauts to the International Space Station.
Jim Cantrell, one of the first employees of SpaceX, did not understand that decision and left the company. In 2015, he started Vector Launch, Inc., with headquarters in Tucson. Its goal is to make the Model T of rockets — small, cheap, mass-produced.
Vector claims that it can send its rockets into orbit from almost any place it can set up its mobile launch platform, which is basically a heavily modified trailer. That trailer was inspired by Mr. Cantrell’s hobby, auto racing, and many of the companies’ employees come from the racing world, too.
The company is still aiming to meet its goal of getting the first of its Vector-R rockets to orbit this year, but Mr. Cantrell admitted that the schedule might slip again, into early 2019. The flight termination system — the piece of hardware that disables the rocket if anything goes wrong — is late in arriving.
“There are a lot of little things,” Mr. Cantrell said. “It drives you crazy.”
A prototype was planned for suborbital launch from Mojave, Calif., in September, but it encountered a glitch and the test was called off. The crew put the rocket in a racecar trailer and drove it to Vector’s testing site at Pinal Airpark, a small airport a half-hour outside of Tucson that is surrounded 350 acres of shrubby desert.
Vector built test stands for firings of individual engines as well as completed rocket stages. During a recent visit to the site, engineers were troubleshooting the launch problems of both the prototype rocket and a developmental version of its upper-stage engine.
Soon the team will head to the Pacific Spaceport Complex, on Alaska’s Kodiak Island, for its first orbital launch. Next year, Mr. Cantrell said, the company hopes to put a dozen rockets into space.
Within a few years, he added, it could be launching 100 times a year, not just from Kodiak but also from Vandenberg Air Force Base in California and Wallops Island in Virginia, where Rocket Lab agreed in October to build its second launch complex. Vector is also looking for additional launch sites, including one by the Sea of Cortez in Mexico.
Resurrected rocketry
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Space analysts wonder how much of a market exists for a behemoth like SpaceX’s Falcon Heavy, which first launched in February. Though it can lift far heavier payloads than the Electron, the Heavy has only a half-dozen announced customers.CreditThom Baur/Reuters
Tom Markusic, another veteran of SpaceX’s early days, also sees an opportunity to help smaller satellites get to space.
“I didn’t feel there was a properly sized launch company to address that market,” he said.
Mr. Markusic said that the need for stronger antennas and cameras would ultimately prompt the construction of slightly bigger small satellites, and that it would be beneficial to be able to launch several at a time.
He started Firefly in 2014, aiming to build Alpha, a rocket that would lift a 900-pound payload to orbit.
The company grew to 150 employees and won a NASA contract. But in the uncertainty surrounding Britain’s exit from the European Union, a European investor backed out. An American investor also became skittish, Mr. Markusic said, after a SpaceX rocket exploded on the launchpad in 2016. Firefly shut down, and the employees lost their jobs.
At an auction, a Ukraine-born entrepreneur, Max Polyakov, one of Firefly’s investors, resurrected the company. Mr. Markusic took the opportunity to rethink the Alpha rocket, which is now able to launch more than 2,000 pounds.
“Alpha is basically Falcon 1 with some better technology,” he said.
Mr. Markusic said his competition was not the smaller rockets of Rocket Lab, Vector or Virgin Orbit but foreign competitors such as a government-subsidized rocket from India and commercial endeavors in China. But he complimented Rocket Lab.
“They’re ahead of everyone else,” he said. “I think they deserve a lot of credit.”
Firefly plans to launch its first Alpha rocket in December of 2019.
Riding the bus to orbit
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A LauncherOne rocket under the wing of a Virgin Orbit Boeing 747, which releases the rocket mid-air at 35,000 feet. CreditGreg Robinson/Virgin Orbit, via Associated Press
Not everyone is convinced that the market for small satellites will be as robust as predicted.
“That equation has weaknesses at every step,” said Carissa Christensen, founder and chief executive of Bryce Space and Technology, an aerospace consulting firm.
Three-quarters of venture capital-financed companies fail, she said, and the same will likely happen to the companies aiming to put up the small satellites. She also is skeptical that space-based internet will win against ground-based alternatives.
“Publicly, there’s no compelling business plans,” she said.
That means that the market for small rockets could implode for lack of business. She said a key to survival would be to tap into the needs of the United States government, especially the military. Virgin Orbit, Vector and Rocket Lab were the current front-runners, she said.
The small rocket companies also have to compete with Spaceflight Industries, a Seattle company that resells empty space on larger rockets that is not taken up by the main payload. In addition, Spaceflight is looking to purchasing entire rockets launched by other companies, including Rocket Lab, and selling the payload space to a range of companies heading to a similar orbit.
The first such flight, using a SpaceX Falcon 9, is to launch from Vandenberg Air Force Base this month carrying 70 satellites, in what the company compares to a bus ride into orbit.
Curt Blake, president of Spaceflight, said that both approaches can work. Buses are cheaper but less convenient, and sometimes the timely lift from a taxi is worth the added cost.
Mr. Anderson of Space Angels was also optimistic. “The difference today is how robust the sector is,” he said. “The sector today can handle failures.”
While the sector is getting off the ground, Rocket Lab doesn’t intend to waste any more time: it is hoping to quickly follow “It’s Business Time” with a second commercial launch next month, and then a third the month after that.
“We’re very focused on the next 100 rockets, not the next one rocket.” Mr. Beck said. “It’s one thing to go to orbit. It’s a whole another thing to go to orbit on a regular basis.”
A research team from Tsinghua University in Beijing has developed a fibre they say is so strong it could even be used to build an elevator to space.
They say just 1 cubic centimetre of the fibre – made from carbon nanotube – would not break under the weight of 160 elephants, or more than 800 tonnes. And that tiny piece of cable would weigh just 1.6 grams.
“This is a breakthrough,” said Wang Changqing, a scientist at a key space elevator research centre at Northwestern Polytechnical University in Xian who was not involved in the Tsinghua study.
The Chinese team has developed a new “ultralong” fibre from carbon nanotube that they say is stronger than anything seen before, patenting the technology and publishing part of their research in the journal Nature Nanotechnology earlier this year.
“It is evident that the tensile strength of carbon nanotube bundles is at least 9 to 45 times that of other materials,” the team said in the paper.
They said the material would be “in great demand in many high-end fields such as sports equipment, ballistic armour, aeronautics, astronautics and even space elevators”.
[…]
Those cables would need to have tensile strength – to withstand stretching – of no less than 7 gigapascals, according to Nasa. In fact, the US space agency launched a global competition in 2005 to develop such a material, with a US$2 million prize attached. No one claimed the prize.
Now, the Tsinghua team, led by Wei Fei, a professor with the Department of Chemical Engineering, says their latest carbon nanotube fibre has tensile strength of 80 gigapascals.
Carbon nanotubes are cylindrical molecules made up of carbon atoms that are linked in hexagonal shapes with diameters as small as 1 nanometre. They have the highest known tensile strength of any material – theoretically up to 300 gigapascals.
But for practical purposes, these carbon nanotubes must be bonded together in cable form, a process which is difficult and can affect the overall strength of the final product.
According to Wang, the space lift researcher, the transport system would need more than 30,000km of cable, and it would also need other structures such as a rail and a shield to protect against space debris and other environmental hazards.
[…]
Japan launched two satellites last month in an experiment to study elevator movement in space – the first time this has been done – involving a mini-lift travelling along a cable from one satellite to another. It has yet to report the results of the experiment. China has also conducted space tethering tests but the details were classified.
[…]
Song Liwei, who studies mechanical batteries at the Harbin Institute of Technology in Heilongjiang, said if the carbon nanotube fibre could be mass-produced and if it significantly increased the energy density of mechanical batteries, it “would kill fossil fuel engines”.
Astrobiologists are mostly interested in rocky exoplanets that lie in the habitable zone around their parent stars, where liquid water may exist on its surface. NASA’s Kepler spacecraft has spotted a handful of these in the so-called Goldilocks Zone – where it’s not too cold or too hot for life.
As such, a second team from Google and NASA’s lab has built a machine-learning-based tool known as INARA that can identify the chemical compounds in a rocky exoplanet’s atmosphere by studying its high-resolution telescope images.
To develop this software, the brainiacs simulated more than three million planets’ spectral signatures – fingerprints of their atmospheres’ chemical makeups – and labelled them as such to train a convolutional neural network (CNN). The CNN can therefore be used to automatically estimate the chemical composition of a planet from images and light curves of its atmosphere taken from NASA’s Kepler spacecraft. Basically, a neural network was trained to link telescope images to chemical compositions, and thus, you should it a given set of images, and it will spit out the associated chemical components – which can be used to assess whether those would lead to life bursting on the scene.
INARA takes seconds to figure out the biological compounds potentially present in a world’s atmosphere. “Given the scale of the datasets produced by the Kepler telescopes, and the even greater volume of data that will return to Earth from the soon-to-be-launched Transiting Exoplanet Survey Satellite (TESS) satellite, minimizing analysis time per planet can accelerate this research and ensure we don’t miss any viable candidates,” Mascaro concluded. ®
By searching for the telltale, periodic dimming of light from distant stars, astronomers can spot orbiting exoplanets tens to hundreds of light-years away. But how do they know what these bodies look like? Perhaps they first try to imagine how the planets in our own Solar System might appear to a faraway alien world.
A pair of scientists has released a detailed catalog of the colors, brightness, and spectral lines of the bodies in our Solar System. They hope to use the catalog as a comparison, so when they spot the blip of an exoplanet, they’ll have a better idea of how it actually looks.
“This is what an alien observer would see if they looked at our Solar System,” study coauthor Lisa Kaltenegger, director of the Carl Sagan Institute at Cornell, told Gizmodo. With this data, astronomers might guess whether an exoplanet is Earth-like, Mars-like, Jupiter-like, or something else entirely.
[…]
All of that incoming data motivated Kaltenegger and coauthor Jack Madden to make this catalog of colors, spectra, and albedos, or how much the planet reflects starlight. They analyzed published data to create fingerprints for 19 objects in our Solar System, including all eight planets, the dwarf planets Pluto and Ceres, and nine moons. Their works is published in the journal Astrobiology.
The full catalog
Graphic: Jack Madden
“It’s smart to leverage everything we know about our own Solar System,” said Kaltenegger. “We have gas giants, the rocky planets, and all these interesting moons. We basically made a reference fingerprint.”
Simulation of the collision: The gas distribution is on the left, stars on the right. (RIT)
