Jupiter Science from Juno Coming Out

The Juno spacecraft has been in orbit around Jupiter since July 2016, and will complete at least two more orbits under current funding (July, 2018).

One of the goals of the mission is to look in detail at the atmosphere of this gas giant.  From Earth, we can see the stripes, which are vast wind streams (in opposite directions ?!), and the Great Red Spot, the largest hurricane in the solar system. But what is going on under the cloud tops?

After more than a year of data collection, results are starting to come in.  Jonathan Fortney summarizes three new papers appearing this spring in Nature [2].  Fortney points out that Earth bound experiments and  theory have not been able to describe the complicated Hydrogen / Helium atmosphere below the surface we can see.

One study investigated the mass distribution of Jupiter by measuring the Doppler effects on the radio signals from the Juno spacecraft as it swooped past [4].  Fortney notes that this was a very finicky process, which had to account for tiny amounts of acceleration including the absorption and re-radiation of sunlight!  The researchers conclude that the bands we see extend quite deep into the atmosphere.

A second study extends this work to conclude that the strong winds decay slowly down some 3.000 kilometers [5].  I.e., the bands we see probably extend down some 3,000 kilometers into the atmosphere.

A third study finds that below that depth, the planet rotates as a solid [3]. At that depth, the pressure is such that the hydrogen ionizes and electromagnetic forces bind the material into a liquid. (This core is the source of the strong magnetic field.)  Obviously, there must be a very turbulent area at the boundary of these two regions, with huge bands of wind ripping East and West across an inner core.

These studies give a picture of a dense interior, with a deep atmosphere dominated by huge bands of strong winds.  An extremely stormy planet!

See swirling cloud formations in the northern area of Jupiter’s north temperate belt in this new view taken by NASA’s Juno spacecraft. The color-enhanced image was taken on Feb. 7 at 5:42 a.m. PST (8:42 a.m. EST), as Juno performed its eleventh close flyby of Jupiter. At the time the image was taken, the spacecraft was about 5,086 miles (8,186 kilometers) from the tops of the clouds of the planet at a latitude of 39.9 degrees. Citizen scientist Kevin M. Gill processed this image using data from the JunoCam imager.

(Caveat:  these studies are based on the theory of gravitational harmonics which I don’t understand at all.)

Fortney suggests that Juno may be able to make further detailed observations of the Red Spot and other storms, which would be interesting details to have.  He also notes that data returned by the Cassini probe of Saturn should yield comparative measurements for the its less dense and probably deeper atmosphere.

Stay tuned. There is lots of other science coming.

The current funding ends in July, but the mission could continue for several more years if supported.

  1. Jonathan Amos, Jupiter’s winds run deep into the planet, in BBC News – Science & Environment. 2018. http://www.bbc.com/news/science-environment-43317566
  2. Jonathan Fortney, A deeper look at Jupiter. Nature, 555:168-169, March 7 2018. https://www.nature.com/articles/d41586-018-02612-y
  3. T. Guillot, Y. Miguel, B. Militzer, W. B. Hubbard, Y. Kaspi, E. Galanti, H. Cao, R. Helled, S. M. Wahl, L. Iess, W. M. Folkner, D. J. Stevenson, J. I. Lunine, D. R. Reese, A. Biekman, M. Parisi, D. Durante, J. E. P. Connerney, S. M. Levin, and S. J. Bolton, A suppression of differential rotation in Jupiter’s deep interior. Nature, 555:227, 03/07/online 2018. http://dx.doi.org/10.1038/nature25775
  4. L. Iess, W. M. Folkner, D. Durante, M. Parisi, Y. Kaspi, E. Galanti, T. Guillot, W. B. Hubbard, D. J. Stevenson, J. D. Anderson, D. R. Buccino, L. Gomez Casajus, A. Milani, R. Park, P. Racioppa, D. Serra, P. Tortora, M. Zannoni, H. Cao, R. Helled, J. I. Lunine, Y. Miguel, B. Militzer, S. Wahl, J. E. P. Connerney, S. M. Levin, and S. J. Bolton, Measurement of Jupiter’s asymmetric gravity field. Nature, 555:220, 03/07/online 2018. http://dx.doi.org/10.1038/nature25776
  5. Y. Kaspi, E. Galanti, W. B. Hubbard, D. J. Stevenson, S. J. Bolton, L. Iess, T. Guillot, J. Bloxham, J. E. P. Connerney, H. Cao, D. Durante, W. M. Folkner, R. Helled, A. P. Ingersoll, S. M. Levin, J. I. Lunine, Y. Miguel, B. Militzer, M. Parisi, and S. M. Wahl, Jupiter’s atmospheric jet streams extend thousands of kilometres deep. Nature, 555:223, 03/07/online 2018. http://dx.doi.org/10.1038/nature25793


Space Saturday


Archaeopteryx could fly

One of the great fossil species of all time, Archaeopteryx (constructed from Greek, “old wing”) was a bolt: clearly bird-like, with feathers, but also clearly as old as the dinosaurs. It was strong evidence that birds evolved a long time ago, and that they existed at the same time as dinosaurs—surprises to biological understanding at the time.

In the 150 years since then, we have found many other ancient birds and bird-like dinosaurs. In fact, contemporary birds are generally recognized as a surviving line of dinosaurs. And in what we know of Archaeopteryx times, it is difficult to unravel which species were “dinosaur-like birds” and which were “bird-like dinosaurs”—if that distinction even makes sense.

The Archaeopteryx itself epitomizes one of the enduring questions: how did birds develop flight.  Many ancient avians (and dinosaurs) have feathers and wings, but appear to be runners.  Presumably, at some point a runner was able to glide and eventually fly.  Could Archaeopteryx actually fly?

One key bit of information relevant to this question is the cross section and interior of bones, which reflect evolutionary adaptation for running and/or flying, and also the mechanical stresses of life. This data isn’t easy to obtain for rare and fragmentary fossils, especially when they cannot be sacrificed in order to examine their interior.

This spring, a European group report on a new study of Archaeopteryx, using contemporary non-destructive imaging [2]. One interesting aspect of the study is that the new measurements allowed Archaeopteryx to be statistically compared to many other animals, including birds and pterosaurs that we know fly or run or both.  The bones show structure similar to contemporary birds, in particular “birds that incidentally employ flapping flight to evade predators or cross physical barriers” (p. 2)  In short, “Archaeopteryx flew like a pheasant” [1].

This finding reminds us that the idea that an animal either “flies” or “doesn’t fly” is unrealistic.  Many birds fly only occasionally, and there are any ways to fly.  And penguins “fly” underwater.

The researchers also point out that the feathered wings of early proto-birds evolved from front limbs and are much more suited to a powered flight (i.e., pheasant-like) than to gliding.  This suggests that some hypotheses about the development of flight should be reconsidered. It isn’t clear that flight developed exclusively from running, then running glide, then powered flight.

Archaeopteryx does not have the fully skeletal features of a modern bird, such as a large ossified sternum.  But the authors suggest that dorsoventral flapping was the early mechanism, and only later evolved to the modern avian flight systems “conceivably promoted by selective pressure towards vertical take-off”.

In this view, modern birds are, not surprising, highly developed fliers, with super valuable specializations to support amazing take off, landing, and maneuvering.

  1. Helen Briggs, Archaeopteryx flew like a pheasant, say scientists, in BBC News – Science & Environment. 2018. http://www.bbc.com/news/science-environment-43386262
  2. Dennis F. A. E. Voeten, Jorge Cubo, Emmanuel de Margerie, Martin Röper, Vincent Beyrand, Stanislav Bureš, Paul Tafforeau, and Sophie Sanchez, Wing bone geometry reveals active flight in Archaeopteryx. Nature Communications, 9 (1):923, 2018/03/13 2018. https://doi.org/10.1038/s41467-018-03296-8

Cryptocurrencies: Yet More Warnings From The Academy

I have noted that the cryptocurrency community has a troubling history of ignoring academic research, even when it ­raises troubling warnings.  In a previous post, I noted that Professor Malkhi warns that the new Ethereum protocol is not secure—and the developers shrug.  And so on.

Now that cryptocurrencies are finally on the academic radar (I’ve been trying to get researchers interested for several years), these incidents are coming fast and often.

IOTA Flaming Out?

 IOTA is an interesting technology that seeks to really implement microtransactions, which they imagine will be useful for the Internet of Things (which they call the “Internet of Ownership”).

As I noted earlier, they whipped up their own hash function, which is a Really Bad Idea ™.   Considering that even half-clever rubes out here in Illinois (me) were aware of this issue as early as last August, it’s quite worrying that they were still using it in December, and then strongly resisted a report of a discovered flaw.  In fact, they accused the academic researchers of fraud and threatened legal action—for daring to report the problem to them.

Not even a shrug, but instead a ferocious counter attack intended to suppress the bad news.


IOTA is a peculiar bird.  They say they want to tackle the challenge of microtransactions which Nakamotoan blockchains really do not handle well.  And they tell the world they are a blockchain / cryptocurrency technology.

But they have no blocks and no chains.  And they have their own weird protocol and until recently, their own home-brew hash function. Notably, the system actually relies on centralized services to work.

They also say they are “open source”, though parts of the system are proprietary.  (Given the experience with the hash function they did publish, I can see that they don’t want people critiquing their code too closely.)

Hmm.  A centralized system with closed source?  That doesn’t seem very blockchain-y to me.

And they are tackling the IOT, which has grievous, deep, and wide security challenges.  Wow!

So what do they have?

They seem to have some technology that is tackling microtransactions (though we can’t really tell what they are doing), and a whole lot of PR.  They seem to be amply stocked with ego, as well.  That part is very Nakamotoan.

Is this something that you would trust?  Probably not.

Ethereum Contracts Have Problems

Ethereum’s “smart contracts” have always been a faith-based technology.  Faith that software can be trusted more than humans.  Faith that people can write error free code. Faith that people on the internet are generally honest.

Since the DAO disaster and ensuing oopsies, you’d think people would lose faith.  But that never happens, and Ethereum was awarded the CryptoTulip of the Year for outstanding achievements in Cognitive Dissonance.

There have been fixes and proposals for improved logic for “smart contracts”, though academic researchers have been trying to climb that particular mountain since Turing’s day.  In the real world, error free programs are so rare as to be unknown.  For that matter, despite millennia of effort, conventional contracts are still imperfect, and always contain escape clauses to deal with disputes and unforeseen developments.  Spoiler alert: “smart contracts” aren’t any smarter than any other contract.

This month researchers from National University of Singapore report a study of Ethereum contracts visible on the blockchain [1]. In general, it is very difficult to analyze the logic of Ehtereum smart contracts because they are complex (running custom languages in the Ethereum Virtual Machine), open-ended (i.e., a contract can call other contracts and services), and execute on any node of the Ethereum  network (i.e., in completely unpredictable environments).

“Contracts are relatively difficult to test, especially since their runtimes allow them to interact with other smart contracts and external off-chain services; they can be in- voked repeatedly by transactions from a large number of users” ([1], p.1)

Instead of logical analysis of each contract, the research studied traces of the contract execution, looking for aberrant behavior that likely reflects a bug.  They examine three patterns that they characterized as greedy, prodigal, and suicidal.

  • ‘Greedy’ contracts lock funds indefinitely.
  • ‘Prodigal’ contracts leak funds to other parties.
  • ‘Suicidal’ contracts are susceptible to being killed by any user.

The comprehensive study scanned over 900,000 (!) Ethereum contracts, executing the logic repeatedly and flagging potential problems.  They found problems in 34,000 (!) some contracts (over 2,000 distinct contracts—there are many replicates in the pool).  Close checking a sample of some 3,000 flagged contracts, they found 89% were confirmed as true bugs.

By my calculation, that’s close to 1 in 3 existing Ethereum contracts that have potentially catastrophic problems.

This is a really cool study.  The researchers likened this to randomly pushing buttons to see what happens, and they heroically pushed all the buttons many, many times.  (Sort of like the current administration’s approach to running the US government.)

It is interesting to note that on the supposedly “transparent” blockchain, less than 1% of the executable contracts had source code available. The study had to analyze execute the bytecodes—which is way harder than analyzing source code.  (But studying the actual bytecodes also revealed bugs in the language and virtual machine that would not be apparent from the source code alone.)

The opacity of these contracts highlights the fact that when you use an Ethereum contract, odds are you are “trusting” the code and other (unknown) people, because you can’t necessarily check the contract. In this supposedly “trustless” system, “faith” replaces “trust”.

Anyway, the result that these contracts contain many serious bugs is scarcely news to anyone who knows anything about programming. In fact, the fact that so many contracts didn’t have problems is really surprising.  Actually, this simply means that there are surely many more bugs that this study wasn’t scanning for.

It will be interesting to see how the Ether heads respond to this report.  My guess is they will shrug.

It is clear that the race for the 2018 CryptoTulip of the Year is wide, wide open.  So much bogosity, so little time to find it all.  But there are more and more competent researchers and actual grown ups investigating the vast acreage of CryptoTulips.

  1. Ivica Nikolic, Aashish Kolluri, Ilya Sergey, Prateek Saxena, and Aquinas Hobor, Finding The Greedy, Prodigal, and Suicidal Contracts at Scale. xariv, 2018. https://arxiv.org/abs/1802.06038
  2. Mike Orcutt, Ethereum’s smart contracts are full of holes, in MIT Technology Review. 2018. https://www.technologyreview.com/s/610392/ethereums-smart-contracts-are-full-of-holes/
  3. Morgen Peck, Cryptographers Urge People to Abandon IOTA After Leaked Emails, in IEEE Spectrum – Tech Talk. 2018. https://spectrum.ieee.org/tech-talk/computing/networks/cryptographers-urge-users-and-researchers-to-abandon-iota-after-leaked-emails



Cryptocurrency Thursday

(Note: This post was edited March 17 to clean up multiple spelling and typos.)

Robot Bonsai Tree

Another cool looking robot demonstration project from Japan:  BonsAI.

Part of the TDK company’s “Attracting Tomorrow” PR campaign, this is an autonomously mobile bonsai.

There have been sensor equipped plants before, and mobile plants, too.  But Bonsai is way, way cooler because it is is esthetically and psychologically much more attuned to human interaction than most plants.

In addition to the standard “seeking sunlight” and “monitoring water” features, the BonsAI seems to “walk beside you” and it is implied that the tree can offer sage advice.  As the website says, “BonsAI is a bit smarter than a man, because it lives longer than a human being.” (Via Google Translate).

It’s not really clear whether this wisdom is metaphorical (as bonsai in general can be said to do), or whether the computer augmentation is actually capable of whispering inscrutable treely wisdom to its human companion. It would certainly be technically possible, though I wonder how psychologically effective it would be.  (Whatever actual voice deployed, it couldn’t possibly sound like a tree to me.)

Overall, this project t gives me mixed feelings.

On the one hand, the bonsai is certainly attractive and sensuous in ways that many robot toys and pets are not.  And, as I’ve said, it is more attractive than most augmented plants. I’d rather cohabit with a robot bonsai than most other personal robots.

But on the other hand, mobility and digital augmentation do little to improve bonsai, which is already a cool augmentation to human life.  Indeed, the digital features may well detract from the value of the bonsai.

For example, part of the pleasure of a bonsai is carefully tending it, which include carefully attending to it. Having sensors that automatically report what the tree needs, or even that autonomously seeks needed sunlight eliminates the need for human attention and effort.  This defeats an important and deep part of the relationship between human and living tree.

I would also note that, on the day that the BonsAI starts emitting advertising, reminders of appointments, or movie recommendations, is the day I say “turn it off”, and chuck it out the window. Ick.


Robot Wednesday


Baby Bird Fossil

Most of what we know of dinosaurs and other ancient life is from fossils, preserved remains of the dead (the rest comes from preserved traces of the dead, such as footprints).  Preservation is an incredible long shot that it isn’t even possible to really estimate just how flukey the fossils we have may be.

It’s not only a crap shoot, but we have to take whatever we can get.  Even when we have hundreds or thousands of specimens (e.g., of T. rex or Tricerotopses), we usually don’t get a good profile of the species.  With only a few shapshots, dominated by large specimens, we have very little information about baby dinosaurs (or anything else), or how they grow up, or even how long they live.

So finding fossils of immature specimens is as huge as it is rare.

This spring a European researchers report on a very rare fossil of a baby bird from the Early Cretaceous—dinosaur times.  This is very definitely a bird (i.e., an avian dinosaur), and shows that the avian line coexisted with the dinosaurs for a long, long time.

The specimen is interesting because it was preserved shortly after birth, and reveals quite a bit about the development of bones, i.e., the hardening of cartilage in the early life of the animal.  For contemporary birds, this process tells us a lot about the growth and behavior of the species.

The researchers interpret the patterns of ossification to suggest that the baby birds would be able to walk, but not be able to fly until later in life.  This confirms a developmental process seen in many ancient and contemporary birds, and strengthens the understanding of these ancestral birds.  On the other hand, there was no evidence of feathers, so it isn’t clear if the baby was naked or had developed its first feathers.

The researchers note that this fossil was actually found years ago, but only recently studied. Recent developments in non-destructive scanning enabled high resolution 3D imaging of this tiny (90mm) specimen, as well as assessment of the degree of ossification of the bones.  It is really cool to find such a tiny treasure in an old rock.  Who knows what else might be out there, already in a drawer someplace?  And who knows what we can discover as we create new and better sensing technology.

  1. Helen Briggs, Baby bird fossil is ‘rarest of the rare’, in BBC News – Science & Environment. 2018. http://www.bbc.com/news/science-environment-43249509
  2. Fabien Knoll, Luis M. Chiappe, Sophie Sanchez, Russell J. Garwood, Nicholas P. Edwards, Roy A. Wogelius, William I. Sellers, Phillip L. Manning, Francisco Ortega, Francisco J. Serrano, Jesús Marugán-Lobón, Elena Cuesta, Fernando Escaso, and Jose Luis Sanz, A diminutive perinate European Enantiornithes reveals an asynchronous ossification pattern in early birds. Nature Communications, 9 (1):937, 2018/03/05 2018. https://doi.org/10.1038/s41467-018-03295-9


WaggleNet: IoT Sensing for Beehives

Yet more Bee research from the University of Illinois Urbana-Champaign: WaggleNet.

This spring undergraduate students report a neat project, implementing an ad hoc sensor net to measure the conditions in Bee hives [1].

The students pulled contemporary technology; low cost, low power computers, radios, and sensors, to implement an inexpensive package suitable to drop in to beehives in the field. The datastreams ping pong from one node to another until they find a router and finally reach an internet connected data repository.  The data can be analyzed to monitor the environment and other aspects of the bee environment.

The prese release notes that this is an interesting project for several reasons.  The initial idea is driven by a “customer”, a bee keeper who wants to monitor the bees over winter.  The technology requires solving the whole end-to-end problem which includes not only the electronics, packaging, and networking, but also dealing with the real world of bee hives.

This is an undergraduate project, and nicely done.  It’s fine that it isn’t exactly ground-breaking.  But let me drop some links  to other work they may want to look at.

This is a great age of sensornets and “smart farming”.

There probably have been many, many beehive sensing projects (not to mention zillions of agricultural sensing designs. I know of at least one project in Utah that is extremely similar to WaggleNet.

The team expresses a desire to make this available to beekeepers everywhere.

I certainly encourage the effort to make an open source version.  I’ll note the “open source hardware” movement as one place to publish it (e.g., see this, this, this, this, this, this, as well as things like Instructables  which has dozens of DiY bee hives and gazillons of DIY sensor projects).  Publishing the whole thing, hardware, software, instructions will take considerable work.  (Contact me if you want some help organizing all this.)

On another front, I’ll point out that if this is to be really used in the world, it wil probably need to be (re-)built with solid security.   if the data is ever to be trusted the system has to be secure.  For that matter, it is important that the sensors and network cannot be hijacked to spy on people or invade other networks.

I know that this product seems harmless and not worth hacking, but unfortunately, that’s just not good enough.  (If the team has any dreams of commercial products, then they really, really need to make things secure from A to Z.)

Again, this is a very nice piece of work.  Making a real produce and/or publishing an open source version will require even more work, and collaborations with additional experts.

  1. Heather Coit, Students Develop Beekeeping IoT for Renowned Research Lab, in Ilinois Enginering – News. 2018. https://engineering.illinois.edu/engage/wagglenet.html

Book review: “The Perfect Nanny” by Leila Slimani

The Perfect Nanny by Leila Slimani

This novel was published in 2016 in French (as Cansons douce), and won the prestigious Prix Goncourt.  While I’ve heard of the Goncourt, this may be the first winner I have read.

The story is grim and psychological, a fictional examination of a tragedy inspired by news reports of nanny’s killing their charges. Indeed, the story opens with the  murder of two young children by their nanny.  How could such a thing happen?

A dark topic, for sure, and Slimani certainly creates a troubling view of the tight and emotionally charged life of young parents and nannies. Even set in Paris, the story is recognizable from large cities in America and elsewhere.  Only the details differ (in Paris, the marginal immigrants are from Africa, in the US they are from Latin America), the deep fears and potential madness seems the same everywhere.

If Slimani meant to illuminate the question, “how could such a thing happen?”, she really doesn’t succeed.  On the other hand, she does tell a story that makes the horrible outcome seem plausible, if not inevitable.

Does that sound pleasant?  It isn’t.

Reading in English translation, it is difficult for me to judge the merits of the original French. I fear that some of the text is rather flat and even opaque, which might reflect an inability to adequately translate the language and cultural references.  For sure, I haven’t a clue about the social geography of contemporary Paris, so I couldn’t guess what baggage might be carried by certain places and events.

Similarly, the characters seem alien to me.  A young mother of Moroccan-French extraction herself, Slimani presumably is writing what she knows.  Is this what the life of a (well off) working mother is like?  Is this what the life of a nanny is?  I don’t know.

Inevitably, the story also touches on the anxieties of immigration and racism in Europe.  This is entangled with nanny questions, because many homecare workers come from the informal and illegal workforce.  This is reported as matter-of-fact part of everyday life in Paris, with very little moral or political comment by the author.

It is natural to wonder how the story reflects Slimoni’s own experience of motherhood and racism.  (She is probably the first to win a Goncourt while pregnant.)

The story surely reflects the anxieties and troubles of motherhood. Like Rachael Cusk, Slimani tells a rather dark vision of motherhood. While Cusk’s characters mostly suffer alone, Slimani describes the complex and difficult relationship of working parents, their children, and nannies. She portrays a tricky situation, where things could suddenly go very wrong, even if they seem to be going right.

OK, we’re starting to get the picture now:  motherhood is awful.  And it is awful even when there is no obvious identifiable cause or cure for the awfulness.

Note to self:  try to find an example of a happy, satisfied mother in contemporary fiction.

  1. Leila Slimani, The Perfect Nanny. Translated by Sam Taylor. New York: Penguin Books, 2018.


Sunday Book Reviews

A personal blog.

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