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April 23, 2019
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Trifecta! SpaceX launches first mission on Falcon Heavy and lands all three boosters

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SpaceX’s Falcon Heavy launch vehicle successfully undertook its first commercial mission today, taking a communications satellite to orbit and proving the viability of its heavy-lift rocket platform. And as a piece de resistance, all three rocket cores autonomously landed themselves back on Earth and will soon be ready to fly again.

The mission is still underway, but the most dangerous moments are over with, and the system passed with flying colors. It’ll be some time before the next second stage burn and separation from the payload, at which point the mission will be considered a success.

Update: Arabsat-6A has detached in the desired orbit and the mission is a success!

The launch is a powerful endorsement of Falcon Heavy, which provides far more payload capacity, at far lower cost, than any competitor. New launch vehicles are being tested by SpaceX’s numerous competitors, but Falcon Heavy has the advantage of already existing and working as designed.

All planned launch events went as planned, though high winds delayed takeoff yesterday. After takeoff at about 6:35 local time in Cape Canaveral, the two first stages detached and made a picture-perfect landing at LZ-1 and LZ-2; the center core landed on the the drone ship Of Course I Still Love You. The latter was a bit of a nailbiter, as the video cut out just as the center core booster’s retro began to light the pad. But good signal a handful of seconds later revealed the final third of the trifecta.

It must be said that the crowd was going absolutely wild basically from T-0 to T+10 minutes, when the center core landed. Landing all three has never been done, and drone ship landings have led to some of SpaceX’s most public (not to say embarrassing) failures.

No word on whether SpaceX caught or attempted to catch the fairings that covered the payload during launch — we may hear about this later, depending on whether it’s a success or not.

News Source = techcrunch.com

Twin astronaut study suggests interplanetary travel may not be a health risk

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The human body “remains robust and resilient” after almost a year in space, according to a long-term, multi-institutional study of twins, one of whom lived aboard the International Space Station for 340 days while the other remained on Earth. These heartening results remove a potential barrier to crewed interplanetary missions — and just in time for us to start planning them.

The study, conducted by NASA and its partners on the American astronauts Scott and Mark Kelly, minutely monitored the twins vitals to see what if any changes occurred to the twin in orbit (Scott) that didn’t to the twin below (Mark). And changes there were, but nothing worrying enough that souls brave enough to go to space will second-guess their profession.

“We have only scratched the surface of knowledge about the body in space,” explained Jennifer Fogarty, chief scientist of NASA’s Human Research Program. “The Twins Study gave us the first integrated molecular view into genetic changes, and demonstrated how a human body adapts and remains robust and resilient even after spending nearly a year aboard the International Space Station. The data captured from integrated investigations like the NASA Twins Study will be explored for years to come.”

There have been previous studies that showed how microgravity and other factors lead to, for example, lower bone density, and consequently the need to address those specific trends with changes to diet or habits. But this is by far the longest anyone has had their health monitored in space, and having a twin on the ground to use as a control body makes for incredibly powerful — yet still limited — results. (Here it seems only fair to note that Mark Kelly is also an accomplished veteran astronaut, not just a “control body.”)

Some expected occurrences included weight loss, lower blood pressure, and eyesight problems due to the lack of gravity. But the length and nature of the study also allowed for several interesting new phenomena in the immunological and molecular domains to be considered. There’s good news and bad news.

Telomeres are parts of our chromosomes that help with, among other things, maintaining our genes. They were immediately affected by presence in space and genetic variation six times that of the control was observed. They lengthened considerably, then upon return to Earth were much shorter than normal. What causes this and what effects it could have are unknown.

That genetic variation also returned to normal when returning to the surface — for the most part. But about 7 percent, many relating to immune response and DNA repair, didn’t. Is there a reason for those genes being affected? It’s impossible to say with a sample size of one. It’s also important to note that these genes weren’t necessarily “damaged” or anything, but that their expression levels had changed. The DNA itself remained intact.

Fortunately, the immune system itself functioned perfectly during and after Scott’s time in space. That’s hugely important, as a weakened immune system could be hugely troublesome on a long, isolated trip to another planet where no additional medical aid can be provided.

The genetic damage may be slightly worrying, but honestly if that’s the biggest issue emerging out of someone spending a year in a can floating through space, it’s seriously good news. The brain (the most critical part of an astronaut) worked great — the circulatory system adapted well — muscles and bones stayed in great shape. Potential telomeric damage and genetic variation aren’t fun, but they aren’t showstoppers either and may very well be preventable.

Considering expeditions to the planned lunar base would almost certainly be longer in duration than those to the ISS, this is great news for the blooming extra-orbital space community. And missions to Mars, as difficult as they may be otherwise, will not have to contend with immune systems shutting down or brain damage from blood pressure changes. That kind of confidence goes a long way.

This study is only the first of many, to be sure, and in fact the teams warn that, because they only had the one person in space as an experimental group, “it is impossible to attribute causality to spaceflight versus a coincidental event. Therefore, our study should be considered as hypothesis-generating and framework-defining and must be complemented in the future by studies of additional astronauts.”

Expect more studies both of this data and whatever gets gathered from future missions to test and verify the results published today. You can read the full paper in the journal Science, and hear much more about the setup and the twins themselves at NASA’s Twins Study page.

News Source = techcrunch.com

Israel’s Beresheet spacecraft is lost during historic lunar landing attempt

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Israel’s SpaceIL almost made history today as its Beresheet spacecraft came within an ace of landing on the surface of the Moon, but suffered a last minute failure during descent. Israel missed out on the chance to be the fourth country to make a controlled lunar landing, but getting 99 percent of the way there is still an extraordinary achievement for private spaceflight.

Beresheet (“Genesis”) launched in February as secondary payload aboard a SpaceX Falcon 9 rocket, and after a month and a half spiraling outward, entered lunar orbit a week ago. Today’s final maneuver was an engine burn meant to bring down its relative velocity to the Moon, then brake to a soft landing in the Mare Serenitatis, or Sea of Serenity.

Everything was working fine up until the final moments, as is often the case in space. The craft, having made it perfectly to its intended point of descent, determined that all systems were ready and the landing process would go ahead as planned.

They lost telemetry for a bit, and had to reset the craft to get the main engine back online… and then communication dropped while only a handful of kilometers from the surface. The “selfie” image above was taken from 22 km above the surface, just a few minutes that. The spacecraft was announced as lost shortly afterwards.

Clearly disappointed but also exhilarated, the team quickly recovered its composure, saying “the achievement of getting to where we got is tremendous and we can be proud,” and of course, “if at first you don’t succeed… try, try again.”

The project began as an attempt to claim the Google Lunar Xprize, announced more than a decade ago, but which proved too difficult for teams to attempt in the timeframe specified. Although the challenge and its prize money lapsed, Israel’s SpaceIL team continued its work, bolstered by the support of Israel Aerospace Industries, the state-owned aviation concern there.

It’s worth noting that Beresheet did enjoy considerable government support in this way, it’s a far cry from any other large-scale government-run mission, and can safely be considered “private” for all intents and purposes. The ~50-person team and $200 million budget are laughably small compared to practically any serious mission, let alone a lunar landing.

I spoke with Xprize’s Founder and CEO, Peter Diamandis and Anousheh Ansari respectively, just before the landing attempt. Both were extremely excited and made it clear that the mission was already considered a huge success.

“What I’m seeing here is an incredible who’s who from science, education, and government who have gathered to watch this miracle take place,” Diamandis said. “We launched this competition now 11 years ago to inspire and educate engineers, and despite the fact that it ran out of time it has achieved 100 percent of its goal. Even if it doesn’t make it onto the ground fully intact it has ignited a level of electricity and excitement that reminds me of the Ansari Xprize 15 years ago.”

He’s not the only one. Ansari, who funded the famous spaceflight Xprize that bore her name, and who has herself visited space as one of the first tourist-astronauts above the International Space Station, felt a similar vibe.

“It’s an amazing moment, bringing so many great memories up,” she told me. “It reminds me of when we were all out in the Mojave waiting for the launch of Spaceship One.”

Ansari emphasized the feeling the landing evoked of moving forward as a people.

“Imagine, over the last 50 years only 500 people out of seven billion have been to space — that number will be thousands soon,” she said. “We believe there’s so much more that can be done in this area of technology, a lot of real business opportunities that benefit civilization but also humanity.”

Congratulations to the SpaceIL team for their achievement, and here’s hoping the next attempt makes it all the way down.

News Source = techcrunch.com

The first research book written by an AI could lead to on-demand papers

in Artificial Intelligence/Delhi/India/machine learning/Politics/Science/TC by

The amount of research that gets published is more than any scholar can hope to keep up with, but soon they may rely on an AI companion to read thousands of articles and distill a summary from them — which is exactly what this team at Goethe University did. You can read the first published work by “Beta Writer” here… though unless you really like lithium-ion battery chemistry, you might find it a little dry.

The paper itself is called, in creative fashion, “Lithium-Ion Batteries: A Machine-Generated Summary of Current Research.” And it is exactly what it sounds like, some 250 pages of this:

The pore structure and thickness of the separator should be carefully controlled, as a satisfactory balance between mechanical strength and ionic electrical conductivity should be kept (Arora and Zhang [40]; Lee and others [33]; Zhang [50]) in order to satisfy these two functions [5]. The pore structure and porosity of the material are clearly quite crucial to the performance of the separator in a battery in addition to the separator material [5].

But as interesting as battery research is, it is only tangential to the actual purpose of this project. The creators of the AI, in an extensive and interesting preface to the book, explain that their intent is more to start a discussion of machine-generated scientific literature, from authorship questions to technical and ethical ones.

In other words, they aim to produce questions, not answers. And questions they have in abundance:

Who is the originator of machine-generated content? Can developers of the algorithms be seen as authors? Or is it the person who starts with the initial input (such as “Lithium-Ion Batteries” as a term) and tunes the various parameters? Is there a designated originator at all? Who decides what a machine is supposed to generate in the first place? Who is accountable for machine-generated content from an ethical point of view?

Having had robust debate already among themselves, their peers, and the experts with whom they collaborated to produce the book, the researchers are clear that this is only a beginning. But as Henning Schoenenberger writes in the preface, we have to begin somewhere, and this is as good a place as any.

Truly, we have succeeded in developing a first prototype which also shows that there is still a long way to go: the extractive summarization of large text corpora is still imperfect, and paraphrased texts, syntax and phrase association still seem clunky at times. However, we clearly decided not to manually polish or copy-edit any of the texts due to the fact that we want to highlight the current status and remaining boundaries of machine-generated content.

The book itself is, as they say, imperfect and clunky. But natural-sounding language is only one of the tasks the AI attempted, and it would be wrong to let it distract from the overall success.

This AI sorted through thousands upon 1,086 papers on this highly technical topic, analyzing them to find keywords, references, takeaways, ” pronominal anaphora,” and so on. The papers were then clustered and organized according to their findings in order to be presented in a logical, chapter-based way.

Representative sentences and summaries had to be pulled from the papers and then reformulated for the review, both for copyright reasons and because the syntax of the originals may not work in the new context. (Experts the team talked to said they should stay as close to the meaning of the original as possible, avoiding “creative” interpretations.)

Imagine that the best sentence from a paper starts with “Therefore, it produces a 24 percent higher insulation coefficient, as suggested by our 2014 paper.”

The AI must understand the paper well enough that it knows what “it” is, and in recasting the sentence, replace “it” with that item, and know that it can do away with “therefore” and the side note at the end.

This has to be done thousands of times and many edge cases pop up where the model doesn’t handle it right or produces some of that admittedly clunky diction. For instance: “That sort of research’s principal aim is to attain the materials with superior properties such as high capacity, fast Li-ion diffusion rate, easy to operate, and stable structure.” Henry James it isn’t, but the meaning is clear.

Ultimately the book is readable and conceivably useful, having boiled down probably ten thousand pages of research to a much more palatable 250. But as the researchers say, the promise is much greater.

The goal here, which doesn’t seem far fetched at all, is to be able to tell a service “give me a 50-page summary of the last 4 years of bioengineering.” A few minutes later, boom, there it is. The flexibility of text means you could also request it in Spanish or Korean. Parameterization means you could easily tweak the output, emphasizing regions and authors or excluding keywords or irrelevent topics.

These and a boatload of other conveniences are inherent to such a platform, assuming you don’t mind a rather stilted voice.

If you’re at all interested in scientific publishing or natural language processing, the preface by the authors is well worth a read.

News Source = techcrunch.com

Flying taxis could be more efficient than gas and electric cars on long-distance trips

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Flying cars definitely sound cool, but whether they’re actually a good idea is up for debate. Fortunately they do seem to have some surefire benefits, among which you can now count improved efficiency — in theory, and on long trips. But it’s something!

Air travel takes an enormous amount of energy, since you have to lift something heavy into the air and keep it there for a good while. This is often faster but rarely more efficient than ground transportation, which lets gravity do the hard work.

Of course, once an aircraft gets up to altitude, it cruises at high speed with little friction to contend with, and whether you’re going 100 feet or 50 miles you only have to take off once. So University of Michigan researchers thought there might be a sweet spot where taking a flying car might actually save energy. Turns out there is… kind of. The team published their results today in Nature Communications.

The U-M engineers made an efficiency model for both ground transport and for electric vertical take-off and landing (VTOL) aircraft, based on specs from aerospace companies working on them.

“Our model represents general trends in the VTOL space and uses parameters from multiple studies and aircraft designs to specify weight, lift-to-drag ratio and battery-specific energy,” said study co-author Noah Furbush in a U-M news release.

They looked at how these various theoretical vehicles performed when taking various numbers of people various distances, comparing energy consumed.

As you might imagine, flying isn’t very practical for going a mile or two, since you use up all that energy getting to altitude and then have to come right back down. But at the 100-kilometer mark (about 62 miles) things look a little different.

For a 100 km trip, a single passenger in a flying car uses 35 percent less energy than a gas-powered car, but still 28 percent more than an electric vehicle. In fact, the flying car is better than the gas one starting at around 40 km. But it never really catches up with the EVs for efficiency, though it gets close. Do you like charts?

ICEV: Internal combustion engine vehicle; VTOL: Vertical takeoff and landing; BEV: Battery electric vehicle. The vertical axis is emissions.

To make it better, they had to juice the numbers a bit bit, making the assumption that flying taxis would be more likely to operate at full capacity, with a pilot and three passengers, while ground vehicles were unlikely to have their average occupancy of 1.5 people change much. With that in mind, they found that a 100 km trip with three passengers just barely beats the per-person efficiency of EVs.

That may seem like a bit of a thin victory, but keep in mind that the flying car would be making the trip in likely a quarter of the time, unaffected by traffic and other issues. Plus there’s the view.

It’s all theoretical right now, naturally, but studies like this help companies looking to get into this business decide how their service will be organized and marketed. Reality might look a little different from theory, but I’ll take any reality with flying cars.

News Source = techcrunch.com

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