All posts by Greg Laden

Everything you always knew about Jupiter is slightly different

A science rocket sent to Planet Jupiter collected information on that giant gas planet’s gravitational field. This has led, through the use of modeling, to the idea that Jupiter was smacked into by another planet early in its life. Bottom line: There should be heavy stuff (heavier than the gasses that make up gas planets) only in a compact core in the middle of the planet, over which the gasses that make it a gas planet accreted. The gravity information seems to suggest that heavy material is distributed more widely.

From the abstract of the paper just out in Nature:

The Juno mission1 has provided an accurate determination of Jupiter’s gravitational field, which has been used to obtain information about the planet’s composition and internal structure. Several models of Jupiter’s structure that fit the probe’s data suggest that the planet has a diluted core, with a total heavy-element mass ranging from ten to a few tens of Earth masses (about 5 to 15 per cent of the Jovian mass), and that heavy elements (elements other than hydrogen and helium) are distributed within a region extending to nearly half of Jupiter’s radius. Planet-formation models indicate that most heavy elements are accreted during the early stages of a planet’s formation to create a relatively compact core and that almost no solids are accreted during subsequent runaway gas accretion. Jupiter’s diluted core, combined with its possible high heavy-element enrichment, thus challenges standard planet-formation theory. A possible explanation is erosion of the initially compact heavy-element core, but the efficiency of such erosion is uncertain and depends on both the immiscibility of heavy materials in metallic hydrogen and on convective mixing as the planet evolves. Another mechanism that can explain this structure is planetesimal enrichment and vaporization during the formation process, although relevant models typically cannot produce an extended diluted core. Here we show that a sufficiently energetic head-on collision (giant impact) between a large planetary embryo and the proto-Jupiter could have shattered its primordial compact core and mixed the heavy elements with the inner envelope. Models of such a scenario lead to an internal structure that is consistent with a diluted core, persisting over billions of years. We suggest that collisions were common in the young Solar system and that a similar event may have also occurred for Saturn, contributing to the structural differences between Jupiter and Saturn

From the press release:

HOUSTON — (Aug. 14, 2019) — A colossal, head-on collision between Jupiter and a still-forming planet in the early solar system, about 4.5 billion years ago, could explain surprising readings from NASA’s Juno spacecraft, according to a study this week in the journal Nature.

Astronomers from Rice University and China’s Sun Yat-sen University say their head-on impact scenario can explain Juno’s previously puzzling gravitational readings, which suggest that Jupiter’s core is less dense and more extended that expected.

“This is puzzling,” said Rice astronomer and study co-author Andrea Isella. “It suggests that something happened that stirred up the core, and that’s where the giant impact comes into play.”

Isella said leading theories of planet formation suggest Jupiter began as a dense, rocky or icy planet that later gathered its thick atmosphere from the primordial disk of gas and dust that birthed our sun.

Isella said he was skeptical when study lead author Shang-Fei Liu first suggested the idea that the data could be explained by a giant impact that stirred Jupiter’s core, mixing the dense contents of its core with less dense layers above. Liu, a former postdoctoral researcher in Isella’s group, is now a member of the faculty at Sun Yat-sen in Zhuhai, China.

“It sounded very unlikely to me,” Isella recalled, “like a one-in-a-trillion probability. But Shang-Fei convinced me, by shear calculation, that this was not so improbable.”

The research team ran thousands of computer simulations and found that a fast-growing Jupiter can have perturbed the orbits of nearby “planetary embryos,” protoplanets that were in the early stages of planet formation.

Liu said the calculations included estimates of the probability of collisions under different scenarios and distribution of impact angles. In all cases, Liu and colleagues found there was at least a 40% chance that Jupiter would swallow a planetary embryo within its first few million years. In addition, Jupiter mass-produced “strong gravitational focusing” that made head-on collisions more common than grazing ones.

Isella said the collision scenario became even more compelling after Liu ran 3D computer models that showed how a collision would affect Jupiter’s core.

“Because it’s dense, and it comes in with a lot of energy, the impactor would be like a bullet that goes through the atmosphere and hits the core head-on,” Isella said. “Before impact, you have a very dense core, surrounded by atmosphere. The head-on impact spreads things out, diluting the core.”

Impacts at a grazing angle could result in the impacting planet becoming gravitationally trapped and gradually sinking into Jupiter’s core, and Liu said smaller planetary embryos about as massive as Earth would disintegrate in Jupiter’s thick atmosphere.

“The only scenario that resulted in a core-density profile similar to what Juno measures today is a head-on impact with a planetary embryo about 10 times more massive than Earth,” Liu said.

Isella said the calculations suggest that even if this impact happened 4.5 billion years ago, “it could still take many, many billions of years for the heavy material to settle back down into a dense core under the circumstances suggested by the paper.”

Isella, who is also a co-investigator on the Rice-based, NASA-funded CLEVER Planets project, said the study’s implications reach beyond our solar system.

“There are astronomical observations of stars that might be explained by this kind of event,” he said.

“This is still a new field, so the results are far from solid, but as some people have been looking for planets around distant stars, they sometimes see infrared emissions that disappear after a few years,” Isella said. “One idea is that if you are looking at a star as two rocky planets collide head-on and shatter, you could create a cloud of dust that absorbs stellar light and reemits it. So, you kind of see a flash, in the sense that now you have this cloud of dust that emits light. And then after some time, the dust dissipates and that emission goes away.”

The Mysterious Russian Nuclear Disaster

Are you following this story from Russia? The Russians lied about it numerous time, and I don’t think we can expect them to ever tell the truth. But it appears to have been a test of a highly improbably weapon (a nuclear powered missile) that resulted in either an explosion that shoved a lot of radioactive material into the atmosphere, or an actual but accidental nuclear explosion.

A village was ordered to be evacuated. Then they cancelled the evacuation.

There is evidence that the bodies of the slain scientists, and/or others injured at the site, who were blasted in the explosion, were so radioactive that the doctors that attended to them also need to be treated. It also may be the case that the nuclear device is in the sea and needs to be recovered.

This is a real mess.

Do Recycle. Don’t Relax

I have two quick things to say about recycling, and these are narrowly focused comments, but please feel free to discuss the issue more broadly in the comments, because I’m writing something more detailed and you can possibly influence that.

1) Do recycle. We have seen a handful of recent reports on authoritative (supposedly) media (like public radio) explaining how the entire recycling industry has collapsed and all the recycling goes into the trash, so YOU should therefore put your recycling in the trash as well. This is INCORRECT at several levels. More on that later. The short version: Let the recycling company decide what gets put in the trash. Your information will never be accurate or up to date compared to theirs.

2) Don’t feel too good about recycling, even if you do it all the time. It isn’t enough to save the planet. Do more. Now. More than that even.

Asimov Book Cheap

Isaac Asimov’s robot books form a somewhat confusing and internally contradictory, but overall fantastic and important corpus of science fiction. One of the Asimov robot books is on sale right now super cheap in Kindle format: The Caves of Steel (The Robot Series Book 1) for $1.99.

Referring to Wikipedia (so get mad at them, not at me, if this seems wrong to you) the robot series of books (not counting short stories) in order of the stories themselves runs something like this:

I, Robot (The Robot Series)

iRobot Roomba 690 Robot Vacuum-Wi-Fi Connectivity, Works with Alexa, Good for Pet Hair, Carpets, Hard Floors, Self-Charging

Bicentennial Man

The Caves of Steel (The Robot Series)

The Naked Sun (The Robot Series)

The Robots of Dawn (The Robot Series)


Richard Dawkins Book Cheap

Did you ever wonder how Richard Dawkins got so smart? Or why he looks so much like Hermione Granger? Well, read this book to find out the answer to those two questions, and so very much more:

An Appetite for Wonder: The Making of a Scientist by Richard Dawkins.

In An Appetite for Wonder, Richard Dawkins shares a rare view into his early life, his intellectual awakening at Oxford, and his path to writing The Selfish Gene. He paints a vivid picture of his idyllic childhood in colonial Africa, peppered with sketches of his colorful ancestors, charming parents, and the peculiarities of colonial life right after World War II. At boarding school, despite a near-religious encounter with an Elvis record, he began his career as a skeptic by refusing to kneel for prayer in chapel. Despite some inspired teaching throughout primary and secondary school, it was only when he got to Oxford that his intellectual curiosity took full flight.

Arriving at Oxford in 1959, when undergraduates “left Elvis behind” for Bach or the Modern Jazz Quartet, Dawkins began to study zoology and was introduced to some of the university’s legendary mentors as well as its tutorial system.

It’s to this unique educational system that Dawkins credits his awakening, as it invited young people to become scholars by encouraging them to pose rigorous questions and scour the library for the latest research rather than textbook “teaching to” any kind of test. His career as a fellow and lecturer at Oxford took an unexpected turn when, in 1973, a serious strike in Britain caused prolonged electricity cuts, and he was forced to pause his computer-based research. Provoked by the then widespread misunderstanding of natural selection known as “group selection” and inspired by the work of William Hamilton, Robert Trivers, and John Maynard Smith, he began to write a book he called, jokingly, “my bestseller.” It was, of course, The Selfish Gene.

Here, for the first time, is an intimate memoir of the childhood and intellectual development of the evolutionary biologist and world-famous atheist, and the story of how he came to write what is widely held to be one of the most important books of the twentieth century.

The plot to overthrow the US Government and install a fascist dictator

There was a time not long ago when the title of this post would invoke in most Americans the assumption of a work of fiction, perhaps a novel by Tom Clancy.

Today, of course, it invokes current events, and looking at that title, one might assume this to be a reference to some current Washington Post story. Indeed, if you came across this post because it was tweeted or facebooked, that is almost certainly what you think we are talking about here.

But no. Continue reading The plot to overthrow the US Government and install a fascist dictator

ALERT!! cPanel is ruining the Internet!

cPanel is a widely used front end used on servers for people to operate things like their blog, email system, other web related functions, etc. It is a way to avoid using the command line. So, for instance, you might buy into a hosing package, and that may allow you to set up a WordPress site. Your host give you the info to log into your own cPanel. There, you press the “one click install” button and whoosh, you have a web site.

cPanel is great because it does things that are critically important in a way that most users can mange.

cPanel sucks because it does that job, sure, but in a way that ends up confusing most users. In other words, the only way to use cPanel unless you already know what you are doing is if you have careful step by step instructions for using cPanel. So, it is only slightly better than the command line.

And now, cPanel has decided to dramatically raise its cost to the extent that most hosts that use cPanel now will have to jettison it or charge more.

I’m letting you know so you can be mad at cPanel. Also, if you know of any OpenSource or reasonably priced alternatives, let’s hear about it.

My personal favorite for alternative: SSH and cli. But I think more is needed.

That is all.

Muslim Advocates Demands Removal of Anti-Muslim Gun Shop Billboard Threatening AOC, Omar, Pressley & Tlaib

A press release:

WASHINGTON, DC — The following is a statement issued today from Muslim Advocates Public Advocacy Director Scott Simpson calling on Cherokee Guns in Murphy, North Carolina and Allison Outdoor Advertising to take down a billboard that invites gun violence against Reps. Alexandria Ocasio-Cortez, Ilhan Omar, Ayanna Pressley and Rashida Tlaib – most of whom have received credible assassination threats. Muslim Advocates is encouraging supporters to send emails to Allison Outdoor Advertising and Cherokee Guns asking them to take the billboard down immediately:

“This billboard puts the lives of these congresswomen in immediate danger and needs to be taken down right away. It labels the four women as harbingers of the apocalypse and then invites people to purchase guns ‘1 mile [ahead] on right.’

These women have already received multiple, credible death threats inspired by similar rhetoric and attacks. Someone has already been charged for an assassination threat against Congresswoman Omar where the suspect said ‘I’ll put a bullet in her fucking skull’ and the assassination attempt that wounded Congresswoman Gabby Giffords was only a few years ago.

Much of the media is irresponsibly downplaying this deeply concerning billboard as ‘mocking.’ This is not a joke and it’s not an insult. This is encouraging gun violence against elected officials.

This is also an anti-Muslim attack. The owners of Cherokee Guns have a Facebook post advertising a similar bumper sticker that is rife with disgusting anti-Muslim slurs including a reference to ‘Infidels for Trump’ and an invitation for patrons to ‘eat a piece of bacon’ to receive the sticker.

Food festivals and houses of worship are being shot up by white nationalists and this billboard invites more violence. Allison Outdoor Advertising must take the billboard down and Cherokee Guns must stop its dangerous, anti-Muslim attacks before the worst happens.”

Muslim Advocates is a national civil rights organization working in the courts, in the halls of power and in communities to halt bigotry in its tracks. We ensure that American Muslims have a seat at the table with expert representation so that all Americans may live free from hate and discrimination.

Dem Debate IIa: Progressive Movement Moves Ahead

It is too early to declare a victory for the Progressive movement in the Democratic Party (obviously) but last night’s debate was a strong sign that there is a strong progressive movement, it is coherent and powerful, and it is winning.

Here’s why I say this, based on preliminary observations of last night’s debatge:

1) The two most progressive candidates, Sanders and Warren, started out well ahead in the polls among this randomly selected large sample of Democratic candidates. The lower down in the polls, within this group of candidates, the least progressive the politician. That is partly a function of who happened to be in this selection, but it is still relevant given that we are talking about ten candidates in one sample.

2) These two progressive candidates did very well in the debate using no apologies, no mincing of words, no side stepping, no clever restating of their positions, and they took no hits on the chin though there were many jabs.

3) The most “centrist” of the other candidates focused on opposing the progressives more than on their own positions, they did so at an apparent cost to party unity, which is going to leave a mark (on them, not the party), and there were a few punches on the chin taken by them, easily delivered by Warren or Sanders. There were times when this looked like two giants swatting flies.

4) The other candidates, who are in my view progressive in their ultimate objectives (mostly) but incrementalist in their approach, tried and partly succeeded to make themselves look like they are progressive in spirit but wiser than the actual progressives. Their supporter will stick with them, but I don’t see much prospect of these candidates gaining after last night.

Anthropologists have long observed that others either imitate the dominant culture, or fight them.

I believe that a number of Democrats who were mostly agnostic about the candidates, or waiting to see, saw and may have moved away from the centrists.

Indivisible conducted a flash poll among members after the debate and found these results:

Warren – 52%
Buttigieg – 19%
Sanders – 13%
Klobuchar – 5%
Williamson – 4%
O’Rourke – 3%
Bullock – 2%
Ryan – 1%
Delaney – 0%
Hickenlooper – 0%

Cheap Bradbury Book, and more

Cheap in Kindle format:

I Sing the Body Electric: And Other Stories

And then also,

On Tyranny: Twenty Lessons from the Twentieth Century by Timothy Snyder.

The Founding Fathers tried to protect us from the threat they knew, the tyranny that overcame ancient democracy. Today, our political order faces new threats, not unlike the totalitarianism of the twentieth century. We are no wiser than the Europeans who saw democracy yield to fascism, Nazism, or communism. Our one advantage is that we might learn from their experience.

On Tyranny is a call to arms and a guide to resistance, with invaluable ideas for how we can preserve our freedoms in the uncertain years to come.

The Eleventh Man: A Novel by Ivan Doig

In the early 1940s, the starting lineup of Treasure State University’s football team are local heroes. But as America is pulled into World War II, they feel called to become heroes of another kind.

Now, ten of them are scattered around the globe in the war’s lonely and dangerous theaters. The eleventh man, Ben Reinking, has been plucked from pilot training by a military propaganda machine. He is to chronicle the adventures of his teammates, man by man, for publication in small-town newspapers across the country like the one his father edits. Ready for action, Reinking chafes at the assignment—not knowing that it will bring him love from an unexpected quarter and test the law of averages, which holds that all but one of his teammates should come through the conflict unscathed .


The 12th Man: A WWII Epic of Escape and Endurance by Astrid K Scott

“I remember reading We Die Alone in 1970 and I could never forget it. Then when we went to Norway to do a docudrama, people told us again and again that certain parts were pure fiction. Since I was a Norwegian that was not good enough; I had to find the truth. I sincerely believe we did,” writes author Astrid Karlsen Scott.

The 12th Man is the true story of Jan Baalsrud, whose struggle to escape the Gestapo and survive in Nazi-occupied Norway has inspired the international film of the same name. In late March 1943, in the midst of WWII, four Norwegian saboteurs arrived in northern Norway on a fishing cutter and set anchor in Toftefjord to establish a base for their operations. However, they were betrayed, and a German boat attacked the cutter, creating a battlefield and spiraling Jan Baalsrud into the adventure of his life. The only survivor and wounded, Baalsrud begins a perilous journey to freedom, swimming icy fjords, climbing snow-covered peaks, enduring snowstorms, and getting caught in a monstrous avalanche. Suffering from snowblindness and frostbite, more than sixty people of the Troms District risk their lives to help Baalsrud to freedom. Meticulously researched for more than five years, Karlsen Scott and Haug bring forth the truth behind this captivating, edge-of-your-seat, real-life survival story.

Food Or War by Julian Cribb: Excellent new book

For many years, scientists who studied biology, behavior, and ecology (under the name of various disciplines) looked at resources, including and especially food, as a major determinant of social structure in social animals, herd structure in herd animals, and so on. Then, there was a revolution and it quickly became apparent that sex, not food, underlies everything and is the ultimate explanation for the variation we see in nature. That pair of dimes lasted for a while, then the other penny dropped and thanks to key research done by a handful of people (including me, in relation to human evolution), it became apparent that there was a third significant factor, that ultimately trumped sex as an organizing force. Food.

I hate it when the author of a book about something historical (history = written records) or even contemporary requires a paleolithic or prehistoric context. If I had a dime for every first chapter I’ve seen where a perfectly expert expert drones ignorantly on about how their book is a follow on of something that started in Olduvai Gorge and side stepped the Neanderthals and all that, I’d have several dollars. Praise the gods that Julian Cribb, in his new book Food or War, only does that for a few paragraphs and does it well!

This book is important, impressive, and a must read.

Food has organized society, politics, war, settlement, colonialism, and the economy more than any single factor, and food has been revolutionized by those things as well. As a simple way to understand this, consider any particular traditional food ask yourself, “would this even be possible were it not for the ability to sail up wind in a ship?” The answer, once you get to it, will almost always be no. Plantains, grass-based cereal crops, maize, potatoes, cassava, a range of vegetables such as tomatoes and various gourds and squash, green leafy things, all of it, are now available to grow in each and every habitat they can be grown in, not just the habitats that happen to be in the geographical region they were domesticated in. And, importantly, this transition happened centuries ago, depending on where one looks. Much of it happened before missionaries or explorers accounts even have a chance to flesh out the details of native live, and certainly long before anthropologists or other professional observers arrived on the scene.

Food or War is the book you must read now to understand the complex historical dynamics behind what you are eating.

The book covers food up to the present, and all the major considerations related to it. Drought, loss of land, climate change, migration, foodies, permaculture, organic farming, and on and on are all addressed in this well written scholarly but for everyone volume. And Cribb makes a stab at projecting into the future, and suggesting what we may consider doing about our food related problems.

This is not a happy book. A book dedicated to Paul Ehrlich is not going to be a happy book. It is a black book with blood red writing and a skull and crossbones on the cover. The title puts an or between the words food and war. This is not the read you need to get you away from the awful discourse polluting our psyches at this moment in history. But it is the book you need to read in order to understand and contextualize many of our policy related problems in the here and now. Plus, it is simply very well written, very well researched, and you will learn things. Many things.

Here’s the TOC:

  1. Food and conflict
  2. War and hunger
  3. The strategic importance of food, land and water
  4. Is ‘agriculture’ sustainable?
  5. Hotspots for food conflict in the twenty-first century
  6. Food as an existential risk
  7. Food for peace
  8. Urban dreams and nightmares
  9. The future of food
  10. Conclusion: key recommendations of this book.

I strongly recommend this book. It is available for pr-order, coming out in September.

New interesting planets found

When a planet passes in front of a star, it is like having the planet in a huge laboratory setting with spectrometers picking up energy from that star as it passes around that planet and through its atmosphere, if it has an atmosphere. It is possible to use this information to estimate the size of the planet and to say something about its composition.

There are two ways in which this super natural laboratory is foiled. One, the star itself is noisy, spitting out a wide range of unruly energy types unpredictably. The other is if the instruments on our end, at Earth, are messed up by things like the atmosphere, or the fact that the Earth is spinning so we can only see the star and planet for a few hours a day.

For these two reasons, astronomers seem to like to do two things. One is to find “quiet” stars, stars that have a steadier output of energy, so they make better backlights, as it were, for the planets. The other is to put instruments on rocket ships and fly them out of the Earth’s atmosphere.

Both things are happening, and it is working.

A new paper in Nature Astronomy reports on a very interesting observation addressing planet types not previously seen much, if ever, and that are missing in our own solar system. They use the term “Missing Link” to refer to planets that are larger and less rocky, or smaller and less gassy, then the Sun’s solar system style plants are.

The abstract says, in part:

One of the primary goals of exoplanetary science is to detect small, temperate planets passing (transiting) in front of bright and quiet host stars. This enables the characterization of planetary sizes, orbits, bulk compositions, atmospheres and formation histories. These studies are facilitated by small and cool M dwarf host stars. Here we report the Transiting Exoplanet Survey Satellite (TESS)1 discovery of three small planets transiting one of the nearest and brightest M dwarf hosts observed to date, TOI-270 (TIC 259377017, with K-magnitude 8.3, and 22.5 parsecs away from Earth). The M3V-type star is transited by the super-Earth-sized planet TOI-270 b (1.247+0.089?0.083 R?) and the sub-Neptune-sized planets TOI-270 c (2.42?±?0.13 R?) and TOI-270 d (2.13?±?0.12 R?). The planets orbit close to a mean-motion resonant chain, with periods (3.36 days, 5.66 days and 11.38 days, respectively) near ratios of small integers (5:3 and 2:1). TOI-270 is a prime target for future studies because (1) its near-resonance allows the detection of transit timing variations, enabling precise mass measurements and dynamical studies; (2) its brightness enables independent radial-velocity mass measurements; (3) the outer planets are ideal for atmospheric characterization via transmission spectroscopy; and (4) the quietness of the star enables future searches for habitable zone planets. Altogether, very few systems with small, temperate exoplanets are as suitable for such complementary and detailed characterization as TOI-270.

An extensive discussion is to be found here at US Riverside’s news agency.

Stem In A Box: Great new toy, er, tool for learning

The Tinkering Labs Electric Motors Catalyst is made for kids about 8-12, but a little younger with supervision and older by a few years is cool.

I’ll put my unboxing shots off to the right so you can get an idea of what the kit contains.

Below, there are a few videos provided by the company in the form of videos, some made by kids who used the kit.

There is an increasing number of tinkering kits on the market, and they vary in two respects: How much different kinds of tinkering you can really do, and how well made the parts are. The Tinkering Labs Electric Motors Catalyst is at the top of the scale for each of these variables, among those I’ve seen. Considering that you get materials to cover STEM principles far and wide in one kit, Tinkering Labs Electric Motors Catalyst might be the cheapest kit (at just over $50, probably) per key concept, especially when compared to the higher priced LEGO offerings and similar.

The kit includes 2 standard electric motors, a battery pack (and batteries), two axles, various wheels made of wood, a large range of metal and wood connectors and shapes including wooden gears, various bolts and such, and a pair of safety goggles, just in case. Especially cute is the Giant Piece Of Blank Paper that will be cut up and used for a variety of things.

Supplementing all the materials, which come with a handy tin to hold hardware and a bag to hold stuff, are several guides and challenge cards and the like. A longer book provides an overview of the numerous building techniques that actually make up the core concepts of the kit, and the challenge cards (with a nice holder) guide the kid in a wide range of different directions.

Parents should be prepared: Things in your house may be … different … after this kit is deployed. But you know what they say. You’ve got to break a few eggs to make an omelets.

And yes, there will be omelets.

Among the most interesting and potentially most fun deployments of this kit involve the supplied various colored markers. This may be a job for the giant piece of paper. Or, perhaps, you have a tile floor and some Mr. Clean? In any event, it is possible to make fast, cheap, and out of control Spirograph with this baby. I wonder if it can be used to decorate a cake?

In addition to this kit containing all you need to make dozens of different things, it would not be difficult to include LEGO parts, erector set parts, or other stuff you happen to have laying around the house.

Note that this is not a robotic toy. The motors are standard motors, not step motors, and there is no logic circuity or controller. This is just rudimentary make it spin and shake technology, as you can see in the various videos supplied below.

I will be bringing this item back in a couple of months to remind you to buy it for some kid at Christmas time. Meanwhile, there are always birthdays.