News Feeds

Actually, this was an unusually homicidal weekend given that it lasted from Thursday (the Fourth of July holiday) through Sunday: four days of shooting opportunities.  And the bad actors were out in force: as everyone reports, there were 109 people shot in that period, 19 of whom died. From ABC News:

One hundred and nine people were shot, 19 fatally, in gun violence across Chicago from midnight Wednesday to midnight Monday during the extended Fourth of July holiday weekend, police said.

CPD Supt. Larry Snelling and Mayor Brandon Johnson both called for accountability for those responsible for the shootings during a press conference on Monday.

“This is a choice. The choice to kill. The choice to kill women, the choice to kill children, the choice to kill the elderly. These are choices that the offenders made and they calculated,” Johnson said. “We are holding every single individual accountable for the pain and from the torment that they have caused in this city.”

Chicago Mayor Johnson and Chicago Police Superintendent Larry Snelling give an update after more than 100 people were shot in Chicago over the 4th of July weekend.

Snelling said adjustments were made after the Fourth of July heading into the weekend, including canceling officers’ days off, but ultimately, he said, they need communities to come forward.

“We have to really stop and think about the mindset of someone who will shoot a child, a helpless child an unarmed mother and think that that’s OK. And go about their days,” he said. “Those people have to be taken off the street. They have to be put away if we’re not doing that. Then we’re failing other families.”

Johnson said he has asked for more resources from the federal government to help invest more resources into communities.

When pressed to address what adjustments need to be made to keep the community safe, Johnson’s response was simply that the city needs more support.

“I am urging all of you across the entire city to step up and say, ‘We’ve had enough,'” Johnson said. “And I’m hopeful that our ongoing discussions will ensure that our state partners, as well as our federal partners, will swiftly come into the support of the city of Chicago. The city cannot afford to wait any longer.”

Well, if you’re a determinist, it’s not really a choice: you could not have done otherwise but pull the trigger. But of course future shootings can be reduced by modifying incentives, behavior, and so on, so determinism doesn’t justify this level of shooting. Further, gun control is vital, but almost useless to fight for given America’s love of guns. (One bright spot: a week ago the Supreme Court decided to leave in place Illinois’s ban on assault-style weapons.)

Brandon Johnson talks the talk, but he doesn’t walk the walk, and weapons are one of the things he needs to deal with as Mayor (not to mention our many potholes that go unfilled). My prediction is that he will not be re-elected, as he’s perceived as a do-nothing mayor. Look at his response when asked what he will do to stop the killings!

One assault occurred only a few blocks from my office on Sunday morning. While driving to the grocery store at 7 a.m., I found my route blocked off by many police cars and “do not enter” tape. I took a roundabout way to the store, and the street was still blocked off when I came back. It turns out that right by the University, three people had been shot at 5:30 that morning. Thank Ceiling Cat that none were killed. And the shooting was only a block from our Emergency Room, so treatment must have been timely.

I suspect this was a gang-related shooting, but the aim was poor: two guys were shot in the leg and one in the nose. (How you can be shot in the nose and survive eludes me, but perhaps the guy was standing in profile.)

In this episode of Dead Planets Society, our hosts place primordial black holes in a variety of objects with surprising results

A digital "primordial soup" with no rules or direction can lead to the emergence of self-replicating artificial life forms, in an experiment that may hint at how biological life began on Earth

As usual, we’re running low, so send in your good wildlife photos.

Today’s selection comes from reader Ruth Berger. Her ID’s and captions are indented, and you can enlarge her photos by clicking on them:

Here is a jumble of pictures taken with a little automatic camera with an 28mm lens in wild-growing greenery in and around industrial areas in Frankfurt, Germany.

My first is of a creature much beloved by me, Trichius cf. gallicus, an unusual-looking beetle:

Trichius spp. belong to the Scarabaeidae whose European members really like Rosaceae plants (but also Asteraceae and many others), so it’s no coincidence I caught this specimen sitting on a Rubus flower. Here is another, better known beetle of the same group, the beautiful and bigger Cetonia aurata, called rose chafer in English; I think the plant is meadowsweet (Filipendula cf. ulmaria), again from the Rosaceae group.

And here are two rose chafers copulating in a hawthorn tree (also a Rosaceae plant). On this very hawthorn tree, about a hundred beetles from several Scarabaeidae species were milling about on that day, while all the other hawthorn trees in the vicinity and in the wider area were blooming away with hardly any visitors. I returned to that same tree a few days later, and again it was buzzing with beetles, as if it had been designated an official meeting point. Do any of the other insect lovers among the readers have any comments about this phenomenon?

Here is a smaller and more homely beetle from the same tree, a male Valgus hemipterus, called stumbling beetle in German. On its left is the backside of a bee, on which more below:

The bee half visible in the previous picture must be some Andrena (mining bee) spp., and here is one of the species it might be (not at all sure about that), a female Andrena haemorrhoa, with its characteristic red thorax plus a fringe of red hair on the end of the abdomen, feeding on a daisy at one of the places where the municipal greenery crew likes to mow whenever a blooming plant other than a daisy opens its petals”

Many Andrena are very versatile and survive that kind of treatment, other genera, not so much. There used to be Ceratina and Hylaeus species on this site, among others, and they are all gone solely due to needless destruction of either their brood or their feeding plants or both over several years.

And now to something completely different, a bumble bee supposedly very frequent but which I see only rarely, Bombus pratorum, the early bumblebee. From both the Latin and the German name (Wiesenhummel), this should be a meadow species, but I saw this one in wooded terrain:

The following is a rare species (“endangered“ according to the German local red list), Mallota fuciformis, a hoverfly posing as a bumble bee, with some similarities to the early bumble bee shown above:

Many hoverflies have obvious mimicry elements in their looks, and one, the hornet mimicry hoverfly, Volucella zonaria, even in behavior: They show the same darting movements as a hornet on the prowl. In flight, they are hard to distinguish from a hornet. Here is a hornet mimicry hoverfly, sitting on the backside of the fence of a garden plot used to raise geese:

Does anyone know the reason why mimicry evolved in hoverflies, but not (to my knowledge) in other families of flies? Here is another hoverfly, Heliophilus trivittatus, a big species I find beautiful (I love the light pastel yellow), sitting on a widow flower, Knautia arvensis, near a river. Heliophilus spp. like it wet. This river meadow was full of widow flowers last year when I took the picture; this year, there isn’t a single one, but lots of clover instead:

As we were recently talking about Vanessa cardui, the Atlantic-crossing painted lady, I herewith present the only semi-decent picture I have of the species (which isn’t that frequent locally), showing it sitting on Buddleja davidii, a plant that is colloquially called butterfly bush because of its attraction to butterflies, although many other pollinating insects love it just as much:

Here is a small tortoiseshell (Aglais urticae) that was right beside it:

The butterfly bush is a neophyte from East Asia that is said to provide only nectar and no pollen, and it isn’t a typical feeding plant for caterpillars either, so it’s considered an invasive pest, although I personally don’t have the impression that it’s outcompeting indigenous flowering plants where I live. Here, it was part of a late-stage ruderal vegetation.

The next picture shows another plant non-native to central Europe (or Britain), the poppy. For reasons unclear to me, poppy flowers seem to be a favorite perching place for larvae stages of long-horned grasshoppers (Tettigoniidae). The one you see here I’d guess is Tettigonia spp. cf. viridissima. The blurry thing on the left is a hoverfly, Episyrphus balteatus, visible in flight towards the poppy.

Poppies are considered archaeophytes in Central Europe (and by extension also Britain and France), as they arrived 8000 years ago with the first farmers who had poppy mixed with their cereal seed. But despite their long presence here, and despite being part of lots commercial flowerseed mixes, they never really went native, or at least that’s my impression: The poppy in the photo grew at the edge of a rapeseed field, and most of the places where I see poppies are either fields and their close vicinity or plots that were used as fields or gardens in the past.

As I wrote the other day:

Don’t forget to bookmark the Snoozy the Squirrel animalcam so you can see her sleeping in the nest or coming and going. I’m pretty sure she’s pregnant and is going to have babies, so keep an eye on the nest.

Snoozy is an eastern gray squirrel (Scirus carolinensis), and their gestation period is about 40-45 days after mating. The young are born without fur, but quickly grow up and leave the nest within 50 days. In the meantime, they’re ineffably cute. With luck, they’ll be born and stay in this nest, though females often move their litters around to escape predation (they seem pretty safe on that ledge). Females have about two litters per year, and this must be the second.

Click on the screenshot below to see her, and don’t forget to click on the “forward” arrow at the lower left.

Snoozy’s cam was down for the weekend, as it has to be reset daily, but she’s back, though right now she’s out foraging. Click on screenshots to see her (or her empty nest. The first photo is from a few minutes ago. Some of her nest seems to have been displaced off the ledge, so perhaps she’s not pregnant after all (or perhaps Snoozy is a Man Squirrel!):

Here she was last evening:

In my role as a teacher and explainer of physics, I have found that the ambiguities and subtleties of language can easily create confusion. This is especially true when well-known English words are reused in scientific contexts, where they may or may not be quite appropriate.

The word “particle”, as used to describe “elementary particles” such as electrons and quarks and photons, is arguably one such word. It risks giving the wrong impression as to what electrons etc. are really like. For this reason, I sometimes replace “particle” with the word “wavicle”, a word from the 1920s that has been getting some traction again in recent years. [I used it in my recent book, where I also emphasized the problems of language in communicating science.]

In today’s post I want to contrast the concepts of particle, wave and wavicle. What characterizes each of these notions? Understanding the answer is crucial for anyone who wants to grasp the workings of our universe.

Why “Wavicle”?

What I like about the word “wavicle” is this.

• First, as a speaker of English or a related language, you may think you know what the word “particle” means. By contrast, you’re probably sure that you don’t know what “wavicle” means. And that’s a good thing! Since electrons’ and photons’ properties are quite unfamiliar, it’s better to bring as few preconceptions along as possible when one first seeks to understand them.
• Second, the word “wavicle” suggests that electrons and photons are more like waves than like dots. That’s true, and important, as we’ll see both today and in the next couple of posts.

Normally the word “particle” in English refers to a little ball or grain, such as a particle of sand or dust, and so an English speaker is imediately tempted to imagine an “elementary particle” as though it were roughly the same thing, only insanely small. But that’s not what electrons are like.

Wavicles are different from particles in several ways, but perhaps the most striking is this: The behavior and the energy of a wavicle are far more sensitive to the wavicle’s surroundings than would be the case for an ordinary particle. That is certainly true of electrons, photons and quarks. Let me show you what I mean.

Side Remark: Is the word “wavicle” really needed?

[An aside: Some might complain that the word “wavicle” is unnecessary. For example, one might propose to use “quantum particle” instead. I’m not convinced that’s any clearer. One could also just use the word “quantum”, the name that Einstein initially suggested. That potentially causes problems, because any vibration, not just waves, may be made from quanta. Well, terminology is always subject to debate; we can discuss this further in the comments if you like.]

A Stationary Particle in a Constrained Space Figure 1: A particle placed at point A has energy E=mc2, no matter how large L is.

Let’s imagine a flat surface bounded by two walls a distance L apart, as in Fig. 1, and place a particle at point A, leaving it stationary. Since the particle is sitting on the ground and isn’t moving, it has the lowest energy it can possibly have.

Why does the particle have its lowest possible energy?

• It’s stationary. If it were to start to move, it would then have additional motion energy.
• It’s at the lowest possible point. If it were lifted up, it would have more energy stored: if it were then released, gravity would convert that stored energy to motion-energy.

How much energy does it have? It has only its internal energy E=mc2, where m is the particle’s mass (specifically, its rest mass), and c is the cosmic speed limit, often called “the speed of light”.

Notice that the particle’s energy doesn’t depend on how far apart the walls are. If we doubled or halved the distance L between the walls, the particle wouldn’t care; it would still have the same energy.

The energy also doesn’t depend on the particle’s distance from the wall. If we placed the particle at point B instead, it would have the same energy. In fact there are an infinite number of places to put the particle that will all have this same, minimal amount of energy.

Figure 2: As in Fig. 1. If the particle is placed at point B instead of point A, its energy is unchanged; it depends neither on L nor on its location.

Such are the properties of a stationary particle. It has a location. It has an energy, which depends only on its local environment and not on, say, faraway walls.

Side Remark: Doesn’t gravity from the walls affect the particle and its energy?

Yes, it does, so my statements above are not exactly true. To be pedantic yet again: the walls have extremely tiny gravitational effects on the particle that do depend on the particle’s location and the distance L. But I have a more important point to make that is independent of these effects, so I’m going to ignore them.

Side Remark: Can all this about “lowest possible energy” really be true? Aren’t speed and energy perspective-dependent?

Total energy, like speed, is indeed a relative concept. So to be pedantically precise: the particle isn’t moving relative to us, and therefore, from our perspective, it has the lowest energy it can possibly have. That’s enough for today; we’ll be sticking with our own perspective throughout this post.

A Standing Wave in a Constrained Space

Waves, in contrast to tiny particles, are often exceedingly sensitive to their size and shape of their containers.

Although we often encounter waves that travel from place to place — ocean waves, earthquake waves, and light waves in empty space — there also stationary waves, known as standing waves, that don’t go anywhere. They stand still, just waving in place, going through a cycle of up-and-down-and-up-again over and over. A famous example of a standing wave would be that on a plucked string, sketched in Fig. 3.

Figure 3: If a string’s ends are held fixed, and the string is plucked, it will vibrate with a standing wave. The wave’s frequency depends on the length of the string (among other things), while its amplitude depends on how firmly it was plucked.

The number of cycles performed by the wave each second is called its frequency. Crucially, if the string’s length is shortened, the frequency of the string’s vibration increases. (This is the principle behind playing guitars, violins, and similar instruments, which play higher musical notes, at higher frequencies, when their strings are made shorter.) In short, the standing wave on a string is sensitive to the length of the string.

More generally, a standing wave has several important properties:

• It has a frequency; the number of back-and-forth cycles per second. In general, if the wave’s container grows wider, the frequency decreases.
  
  
• It has a wavelength — the distance between highpoints on the wave — which will increase if the container widens. (I won’t discuss wavelength here, as it doesn’t play a role in what follows.)
  
  
• It has an amplitude (or “height”) — which describes how far the wave extends away from its midpoint during each cycle. Unlike frequency and wavelength, which are determined in part by the container’s size, the amplitude is independent of the container and is adjustable. For instance, for the string in Fig. 3, the amplitude (the vibrating string’s maximum extension in the vertical direction) depends on how firmly the string was plucked, not on the string’s length.

For instance, if we take the two walls of Fig. 1 a distance L apart, and we put a simple standing wave there, we will find that the frequency decreases with L, the wavelength increases with L, and the amplitude and energy depend on how “high” the wave is, which has nothing to do with L.

Figure 4: A standing wave extending between two walls; it has a frequency (how many cycles per second), an amplitude (how far back and forth does it go) and a wavelength (2L in this case.)

Unlike particles, waves have neither a definite location nor a determined energy.

• A standing wave has no definite location; it is inevitably spread out.
• A standing wave has an adjustable energy; if one increases or decreases the wave’s amplitude, its energy will similarly increase or decrease. (For instance, plucking a guitar string harder puts more energy into the vibration of the string, and leads to a standing wave with a larger amplitude and energy — one which will in turn create a louder sound.)

Particles, meanwhile, have neither frequency, amplitude nor wavelength.

A Standing Wavicle in a Constrained Space

Wavicles differ from both waves and particles. Like a wave, a wavicle is spread out, and can have a definite frequency, unlike a particle. But unlike a wave, a wavicle’s amplitude and energy are not adjustable, and so, like a particle, it can have a definite, fixed energy.

In particular, thanks to a formula that Max Planck guessed and Albert Einstein correctly reinterpreted, a wavicle’s energy and frequency are precisely proportional; if you know one, you know the other. The formula?

• E = f h

where E is the wavicle’s energy, f its frequency, and h is called Planck’s constant. (I sometimes refer to this constant as the cosmic certainty limit, in parallel to c being the cosmic speed limit; but that’s a personal quirk of mine.)

Photons, electrons and quarks are all wavicles, and they share many properties. There is, however, a crucial difference between them: the rest mass of a photon is zero, while that of an electron or quark is positive. This difference affects how their frequency and energy depend on L when they form standing waves in a box. (The differences between the standing waves for these two types of wavicles are shown in this article.)

Let’s look at photons first, and then at electrons.

Photon in a Box

If a photon is trapped in a box, forming a standing wave much like a standing wave on a guitar string, then the minimum frequency of that photon is set by the size of the box L and the cosmic speed limit:

• f = c / L

(Here I’m slightly over-simplifying; since the box is really three-dimensional, not one-dimensional as I’ve drawn it, the formula is slightly more elaborate. See below for the more complete math formulas if you want them.)

But the energy of the photon is also determined, because of the formula E = f h, which implies

• E = h c / L

Therefore, as L shrinks, E rises: the smaller the box, the larger the frequency and energy of the photon.

If the box’s size goes to infinity, the photon’s frequency and energy both go to zero. This reflects the fact that light on its own, isolated from other objects such as a box, cannot form a standing wave. In empty space, light and the photons that make it up are always traveling waves; they can only stand when inside a container.

Click here for more complete formulas for a photon in a box

A three-dimensional, the box has a length, width and height , and the photon’s frequency is



If the box is a cube with sides of equal length , then



The relation is still true, so

I claimed earlier that the energy of a wave is adjustable, while that of a wavicle is not. In this context, that means that the energy of a laser beam can be adjusted, but the energy of the individual photons that make up the laser beam cannot be. How does this work?

Let’s combine N photons of frequency f together. Then we get a wave of frequency f, with energy N times larger than that of a single photon.

• E = N f h

And thus, by adjusting N, making the wave’s amplitude larger, we can adjust the energy E if the wave. (How big might N be? HUGE. If you turn a laser pointer on for one second, the wave emitted by the pointer will typically have N somewhere in the range of a million billion or more.)

By contrast, a single photon corresponds to N = 1. Nothing else can be adjusted; if the photon has frequency f, its energy is fixed to be f h. That energy cannot be changed without also changing f.

Electron in a Box

An electron, unlike a photon, can be a standing wave (and thus stationary) even outside a box. This is a point I emphasized in this post, where I described a type of standing wave that can exist without walls, i.e., without a container.

Such an electron, sitting still and isolated out in empty space, has energy

• E = mc2

where m is the electron’s mass. But since it is a wavicle, E = f h; and so [as discussed further in the book, chapter 17] its frequency is

• f = E / h = m c2 / h

Again, the idea that an electron has a frequency makes sense only because it is a wavicle; were it really a particle, we would be hard pressed to understand why it would have a frequency.

When the electron is placed inside a box of length L, its energy and frequency increase, just as is the case for a photon. However, whether the increase is large or small depends on whether the box is larger or smaller than a certain length, known as the electron’s Compton wavelength Le . That length is

• Le = h c / m = 2 x 10-12 meters

This distance is much smaller than an atom but much larger than a proton or neutron; specifically, it is about a hundredth of the radius of an atom, and about a thousand times larger than the radius of a proton.

Much depends upon the relation between L and Le.

• In a small box, where L is much less than Le , the effect of the box on the electron’s frequency and energy can be very large. In particular, it can make E much bigger than mc2 !!
• In a large box, where L is much greater than Le, then E will be only slightly bigger than mc2.

This behavior of the frequency (and thus the energy) of an electron, as a function of L, is shown in Fig. 5, along with the different behavior of the frequency for a photon. (These two types of behavior of frequency as a function of box size were also shown in this article.) We’ll come back to this in a later post, when we see how it is relevant for atoms.

Figure 5: The frequency of wavicles in a box. As L increases, a photon’s frequency f (orange) decreases as 1/L. An electron’s frequency (blue) is different. In an infinite box (infinite L) the frequency is mc2/h, where m is the electron’s rest mass (green dashed line.) In a large box, the frequency is just slightly above mc2/h. But when L is smaller than the electron’s Compton wavelength Le = mc/h, then the electron’s frequency behaves as 1/L, similarly to a photon’s. Click here for the more complete formulas for an electron in a box

Compare the following with the complete formulas for a photon, given above. The electron’s frequency in a box whose sides have different lengths is



If the box is a cube whose sides have equal length , then



The relation is still true, so

Thus if , then is very slightly larger than , whereas if then , just as for a photon.

Something similar is true for the up and down quarks, and indeed for any “elementary particle” that has a non-zero rest mass. This has relevance for protons and neutrons, a point to be addressed in a later post.

One last point about electrons. If the box is huge — if L is much, much greater than Le — then the electron can exist for a very long time as a localized standing wave, occupying only a small part of its box. This allows it to behave more like the particle in Fig. 1, tightly localized at a point, than like the wave of Fig. 4, which entirely fills the box. (Again, see this post on unfamiliar standing waves.) In that circumstance, the electron won’t have the lowest energy it can possibly have — to reach that low enerrgy would require filling the entire box — but its energy will still exceed mc2 by only a minuscule amount.

This illustrates another crucial fact: wavicles with rest mass can sometimes be much more particle-like than wavicles without rest mass, with an approximate location as well as an almost definite energy. It’s another reason why scientists initially thought electrons were particles (in the usual sense of the word) and were slow to understand their wave-like properties.

A Comparison

To sum up, particles don’t have frequency, and waves don’t have their energy tied to their frequency; it’s having both frequency and specific associated energy that makes wavicles special. A key feature of a wavicle is that when you make it stationary and put it in a box, its frequency and energy generally increase; the smaller the box, the greater the effect. As seen in Fig. 5, the increase is particularly dramatic if the box is comparable to or smaller than the particle’s Compton wavelength.

To help you remember the differences, here’s a table summarizing the properties of these objects.

stationary particlestanding wavestanding waviclelocationdefiniteindefiniteindefiniteenergydefinite, container-independentadjustabledefinite, fixed by frequencyfrequencynonecontainer-dependentcontainer-dependentamplitudenoneadjustablefixed by frequency & container
A stationary particle, standing wave, and standing wavicle, placed in an identical constrained space and with the lowest possible energy that they can have, exhibit quite different properties. The Old and New(er) Quantum Physics

Niels Bohr was one of the twentieth century’s greatest physicists and one of the founders of quantum physics. Back in the late 1920s and early 1930s, in his attempt to make sense of the confusions that quantum physics generated among the experts, he declared that electrons are both wave and particle — that depending upon context, sometimes one must view an electron as a wave, and sometimes one must view it as a particle. (This “wave-particle duality” lies at the heart of what came to be called the “Copenhagen interpretation of quantum physics.”)

But this was back in the days before quantum field theory, when quantum physics was very new. The quantum theory of the 1920s did indeed treat electrons as particles — with positions, yet described by a wave-function. It didn’t treat photons in the same way. It was only later, in the middle of the century, that quantum field theory came along. Quantum field theory put electrons and photons on exactly the same footing, treating both as wavicles, described by a single, overall wave-function. (Important! be sure not to confuse wavicles with the wave-function; they are completely different beasts!!)

This quantum field theory viewpoint didn’t really fit with Bohr’s vision. But it’s quantum field theory that agrees with experiment, not the quantum physics of Bohr’s era. Nevertheless, Bohr’s interpretation persisted (and still persists) in many textbooks and philosophy books. I learned about it myself at the age of sixteen in a class on the philosophy of science. That was several years before I learned the mathematics of quantum field theory and began to question Bohr’s thinking.

From the perspective of quantum field theory, as I’ve outlined here, a wavicle does have features of both waves and particles, but it also lacks features of both waves and particles. For this reason, I would personally prefer to say that it is neither one. I don’t think it’s useful to say that it is both wave and particle, or to say that it is sometimes wave and sometimes particle. It’s simply something else.

But this is something we could debate, and perhaps some readers will disagree with me. I’m happy to discuss this in the comments.

That said, however, I do want to emphasize strongly that using “wavicle” does not in any way help resolve the most confusing issues with quantum physics. Adopting “wavicle” does not make it any easier to understand, for instance, the quantum double slit experiment or the issue of entanglement’s “spooky action at a distance”. I do think quantum field theory has the advantage of removing certain unnecessary confusions, making it somewhat easier to state the problems of quantum physics. But this makes them no easier to resolve.

Such issues, however, are a topic for another time.

In an optimally rational person, what should govern their perception of risk? Of course, people are generally not “optimally rational”. It’s therefore an interesting thought experiment – what would be optimal, and how does that differ from how people actually assess risk? Risk is partly a matter of probability, and therefore largely comes down to simple math – what percentage of people who engage in X suffer negative consequence Y? To accurately assess risk, you therefore need information. But that is not how people generally operate.

In a recent study assessment of the risk of autonomous vehicles was evaluated in 323 US adults. This is a small study, and all the usual caveats apply in terms of how questions were asked. But if we take the results at face value, they are interesting but not surprising. First, information itself did not have a significant impact on risk perception. What did have a significant impact was trust, or more specifically, trust had a significant impact on the knowledge and risk perception relationship.

What I think this means is that knowledge alone does not influence risk perception, unless it was also coupled with trust. This actually makes sense, and is rational. You have to trust the information you are getting in order to confidently use it to modify your perception of risk. However – trust is a squirrely thing. People tend not to trust things that are new and unfamiliar. I would consider this semi-rational. It is reasonable to be cautious about something that is unfamiliar, but this can quickly turn into a negative bias that is not rational. This, of course, goes beyond autonomous vehicles to many new technologies, like GMOs and AI.

There also appears to be a bias toward lack of trust in things that are highly complex. If someone has a hard time understanding the underlying science, their default position is negative. People are also biased towards information they recently encountered. So if someone sees a story on the news about an accident involving an autonomous vehicle, that will have more influence on their attitude than statistics. It is also easier to stoke fear than engender confidence. People have a risk-avoidance bias. One negative rumor about vaccines, nuclear power, or GMOs can cause a lot of risk avoidance that will be difficult to counter with information.

What about deference to experts and scientific authority? In this study reported deference to scientific experts did not modify the relationship between information and trust, but it did modify the impact of trust on risk perception. However, the desire for a new experience had a positive effect on the perception of risk. What does all this mean?

One take-away from this and many other studies that touch on this question is that there is a nuanced and complex relationship among the public perception of risk, reality, and public communication of information. Many factors shape public perception, including media reporting, the effectiveness of science communication, sensationalism, statistics, fear, the cool-factor, and trust in the relevant institutions. This also means that effective advocacy for science-based policy and public behavior is challenging.

The general media play a mixed role, but by my perception it is largely a negative one. They do provide information, for those who wish to avail themselves, but they are biased toward sensationalism, dramatic events, fearmongering, and fringe opinions. Fear, shock, drama, and spectacle drive clicks, but these are not the best way to make cold rational decisions.

Activist groups with an ideological agenda also have an easier time stoking fear and misinformation than science-based groups trying to improve public knowledge and perception. The anti-GMO campaign is a great example – it is based entirely on fear, distortion, and misinformation and yet has managed to convince a majority of the public that GMOs are something to be feared. Anti-vaccine campaigns also scare a lot of parents away from a safe and effective public health measure.

Those of us pushing for a science-based approach to these questions have many challenges. We cannot just give facts and information. The data shows that this is usually not enough (although it does help). We need to create scientific literacy, critical thinking skills, and media savvy. People need to understand that they have been manipulated by misinformation, and that they can be empowered with a more reality-based perspective.

But perhaps the most frustrating challenge is that trust itself is a complicated issue. There is no single source or institution that we can trust absolutely, and yet trust is essential. There are many examples of institutions lying, of researchers committing fraud, of experts just getting it wrong, and of governments covering up their failings. I find this the most challenging thing to communicate. People don’t deal well with complexity and nuance. We prefer simplicity and absolutes. This leads some people to effectively take the approach of – if I can’t trust absolutely, then I won’t trust at all. This means they will essentially believe whatever they want. This just leads to dueling experts and competing narratives.

The skeptical approach is – reality is messy, information is complicated, and trust is relative, but we can use a process to determine that some conclusions are more likely to be true than others. Conclusions are tentative, partial, qualified, and subject to revision, but it’s still better to make decisions on the best current information available than to live life as a “choose your own adventure” story.

The post Trust in New Technology first appeared on NeuroLogica Blog.

US start-up Savor says its synthetic vegan fat, made without livestock or the crops needed for margarine, could cut carbon emissions and save rainforests

Welcome to the Cruelest Day: Tuesday, July 9, 2024, and National Sugar Cookie Day, the simplest of all cookies but not the worst. This photo, from Wikipedia, suggests to me that they should be dunked in coffee:

AceDragonfly, CC BY-SA 4.0 via Wikimedia Commons

It’s also Martyrdom of the Báb, Cow Appreciation Day, National No Bra Day (this was the norm when I was in college), Fashion Day, Constitution Day in Australia and Nunavut Day (in Nunavut, of course).

Readers are welcome to mark notable events, births, or deaths on this day by consulting the July 9 Wikipedia page.

Da Nooz:

*The French elections were a surprise with the right-wing Rally Party not winning. Actually, nobody won. From the BBC:

Nobody expected this. High drama, for sure, but this was a shock.

When the graphics flashed up on all the big French channels, it was not the far right of Marine Le Pen and her young prime minister-in-waiting Jordan Bardella who were on course for victory.

It was the left who had clinched it, and Emmanuel Macron’s centrists – the Ensemble alliance – had staged an unexpected comeback, pushing the far-right National Rally (RN) into third.

Jean-Luc Mélenchon, the veteran left-wing firebrand seen by his critics as an extremist, wasted no time in proclaiming victory.

“The president must call on the New Popular Front to govern,” he told supporters in Stalingrad square, insisting Mr Macron had to recognise that he and his coalition had lost.

His alliance, drawn up in a hurry for President Macron’s surprise election, includes his own radical France Unbowed, along with Greens, Socialists and Communists and even Trotskyists. But their victory is nowhere big enough to govern.

Here’s Matthew’s take on it, posted with permission:

It’s all rather complicated.

France has a two-round system. In the first round, if a candidate gets >50%, they are elected straight away (this is relatively rare). If no one gets a majority in the first round, all candidates with >12.5% of the vote can go through to the second round, which is straight first-past-the-post.

In the first round, the Rassemblement National (National Rally – ex-Front National) was the largest single party, but did not win any seats outright. The evident threat was that they would go on and win a parliamentary majority in the second round. In the run-up to the election, the left parties – Unbowed France, Socialist Party, Communist Party, Greens, and some small groups – came together as the New Popular Front (a reference to the Popular Front of 1936) put forward a common programme and a single candidate in each constituency. As soon as the results of the first round were known, the NPF said they would stand down their candidates in the second round where they came third, behind a right-wing candidate, in order to beat the FN. The right-wing parties were much less prepared to reciprocate, and in many cases maintained their candidacy, even when they had come a poor third.

In the week or so before the election, although the pollsters and pundits were predicting an RN absolute majority, the racist and anti-semitic nature of some of their candidates was revealed; together with the mobilisation of the left parties, this was sufficient to ensure that the RN were pushed into third place, with the NPF getting the largest number of seats. This was a huge relief to many people – hence the joyous scenes in many cities around France. In the cases where right-wingers stood as a third candidate, they were all defeated.

However, no party, and no group of parties on the same political wavelength, has a majority. This is a hung parliament. Whoever is the future prime minister (the current PM, from Macron’s party, has offered his resignation but has been asked to stay on for a while) will have to negotiate legislation on a case-by-case basis. This is not new – Macron’s party has been a minority government for the last two years.

Macron called the early elections because he wanted to lance the boil of the RN, which had done remarkably well in the European elections. He obviously really wanted his party to gain a majority (the only reason he was elected – twice – is because he was standing against the leader of the RN, Marine Le Pen, and he clearly hoped that might happen again, at a parliamentary scale). Things didn’t work out quite as he hoped – he now has to deal with the legitimate claim of the NPF that it should form the new government. There will be a lot of horse-trading in the coming weeks. If the NPF does form a government, one of its key measures would be to halt the attacks on pensions that have been a key part of Macron’s policies and which have provoked enormous discontent. While this policy would be opposed by the traditional parties of the right, it did feature in the RN”s manifesto, so could technically pass in parliament…

*Biden is holding very firm about remaining the Democratic candidate for President, and he even wrote a letter to Congressional Democrats saying he’s committed to staying in the race:

President Biden issued defiant responses on Monday to high-ranking lawmakers calling for him to step aside, challenging Democrats to run against him and telling congressional Democrats in a letter that he was “firmly committed to staying in the race.”

Calling into “Morning Joe” on MSNBC, Mr. Biden said he didn’t care about any of the “big names” urging him to drop out of the race, his voice rising considerably as he spoke.

“If any of these guys don’t think I should run, run against me,” he said. “Go ahead, announce for president. Challenge me at the convention.”

Less than an hour earlier, Mr. Biden’s campaign released a letter to congressional Democrats in which he wrote that he was “firmly committed to staying in the race.”

His pledge to remain in the race kicks off what could be the most crucial week of his presidency, as he faces crumbling support from Democratic lawmakers and mounting fears of a rout by former President Donald J. Trump and his followers in November’s races for the White House and Congress.

Here’s an excerpt from his letter:

Let’s have a poll. Will he stay or will he go?

Note: There is a poll embedded within this post, please visit the site to participate in this post's poll.

*The descriptions of negotiations between Israel and Hamas have been confusing, but yesterday Israeli PM Benjamin Netanyahu has issued a list of  four “nonnegotiable demands” that, he says, he’ll stick to during the negotiations. From the Times of Israel:

Ahead of the Israeli negotiating team’s departure for further hostage deal talks in Cairo and Doha later this week, Prime Minister Benjamin Netanyahu presented a list on Sunday evening of what he said were four nonnegotiable Israeli demands, including a guarantee that Israel could resume fighting, which would need to be met in any hostage release and ceasefire deal with Hamas.

Netanyahu’s statement, at a crucial phase ahead of the resumption of talks, sparked anger, both in Israel and among mediators, with some accusing him of attempting to sabotage hard-won progress.

The renewed negotiations in both Egypt and Qatar come after the Hamas terror group said on Saturday that it was ready to discuss a hostage deal and an end to the war in Gaza without an upfront commitment by Israel to a “complete and permanent ceasefire.” That statement constitutes a shift in the position Hamas has held in all previous negotiations since November.

Here are the four nonnegotiable demands:

1. “Any deal will allow Israel to return to fighting until its war aims are achieved.”

2. “Weapons smuggling to Hamas from the Gaza-Egypt border will not be possible.”

3. “The return of thousands of armed terrorists to the northern Gaza Strip will not be possible.”

4. “Israel will maximize the number of living hostages who will be returned from Hamas captivity.”

#1 is probably not acceptable to Hamas, for it would force them surrender (see also #3), though it’s not clear that this will eventually remove Hamas from power.  And #4 is a bit ambiguous; it should say “Hamas must return ALL the hostages, living or dead. Despite the fact that many of the Israeli public seem willing to keep Hamas in power if they just let the hostages go, I don’t think keeping Hamas in power is in Israel’s interests.

*Columbia University has fired the three deans who became infamous for exchanging anti-Semitic text messages during presentations about antisemitism by rabbis and other pro-Jewish people. (The text messages were photographed over the shoulders of the texting deans.)

Three Columbia University administrators have been removed from their posts after sending text messages that “disturbingly touched on ancient antisemitic tropes” during a forum about Jewish issues in May, according to a letter sent by Columbia officials to the university community on Monday.

The administrators are still employed by the university but have been placed on indefinite leave and will not return to their previous jobs.

Nemat Shafik, the Columbia president, described the sentiments in the text messages as “unacceptable and deeply upsetting, conveying a lack of seriousness about the concerns and the experiences of members of our Jewish community.” She said the messages were “antithetical to our university’s values and the standards.”

The announcement came about a month after a conservative website published photos that showed some of the text messages sent by the administrators.

And it followed weeks of unrest at Columbia over the war in Gaza as the university emerged as the center of a nationwide protest movement. Pro-Palestinian demonstrations led Dr. Shafik to order the arrest of students on trespassing charges this spring. In late April, protesters occupied a campus building, leading to more arrests. In May, citing security concerns, the university canceled its main commencement ceremony.

The three Columbia administrators involved in the text message exchanges are Cristen Kromm, formerly the dean of undergraduate student life; Matthew Patashnick, formerly the associate dean for student and family support; and Susan Chang-Kim, formerly the vice dean and chief administrative officer. They did not immediately respond to requests for comment.

Josef Sorett, the dean of Columbia College, also engaged with the administrators in the text exchange.

He will remain in his post, according to the university provost, Angela V. Olinto.

Remember that they’re not FULLY fired, as they’re on leave, presumably not getting paid, and one source said that they’re just being “reassigned.” Also remember that the arrested Columbia students, with (I think) one exception, had all their charges dropped, though I don’t know whether they’ll get disciplined internally by Columbia.

At least the school did SOMETHING about the deans, though. It’s pretty damn embarrassing to have several deans joking and making antisemitic remarks during a symposium on Columbia’s Jewish issues. I am surprised that Sorett remains in office, given that he was involved in the text exchange, but maybe he didn’t say anything antisemitic. (Plus he’s the Big Dean.) One might think that this is free speech, but it’s a violation of institutional neutrality and I think deans serve at Columbia’s will.

*The undisputed king of hot-dog eating, Joey Chestnut, didn’t compete in Nathan’s annual wiener-eating contest this year, so somebody else won. But, wolfing down the pups in another location, Chestnut made the winner look bad.

Patrick Bertoletti gobbled up 58 hot dogs to win his first men’s title Thursday at the annual Nathan’s Famous Fourth of July hot dog eating contest, taking advantage of the absence of the event’s biggest star. In the women’s competition, defending champion Miki Sudo won her 10th title and set a new world record by downing 51 links.

Joey “Jaws” Chestnut, the reigning men’s champion and winner of 16 out of 17 previous competitions, didn’t attend this year over a sponsorship tiff. Instead he competed later in the day against four soldiers at a U.S. Army base in El Paso, Texas, where he wolfed down 57 hot dogs in five minutes.

Bertoletti, 39, of Chicago, won in a tight, 10-minute race where the leader bounced back and forth, defeating 13 competitors from around the world. He said he lost weight and practiced for three months with “an urgency” to prepare for the event, thinking he had a good chance of winning.

“With Joey not here, I knew I had a shot,” Bertoletti said. “I was able to unlock something that I don’t know where it came from.”

Bertoletti bested his prior record of 55 hot dogs at the event, which is held every Independence Day on New York’s Coney Island, a beachfront destination with amusement parks and a carnivalesque summer culture.

Chestnut: 57 dogs in five minutes.  Bertoletti: 58 dogs in ten minutes. Chestnut was almost twice as fast. In fact, Chestnut was banned from the Nathan’s contest because he signed a deal with Impossible Foods, which makes vegan dogs! (I’m not sure the 58 dogs Chestnut ate in Texas were vegan or not.) But here’s Bertoletti (the female champion, Miki Sudo, downed 51 dogs, a really good total for a woman).

Meanwhile in Dobrzyn, Hili is kvetching:

Hili: Do people still write books? A: Of course, why do you ask? Hili: Its been a long time since you bought any. In Polish: Hili: Czy ludzie jeszcze piszą książki? Ja: Oczywiście, dlaczego pytasz? Hili: Dawno żadnej nie kupowałeś.

. . . and a lovely picture of Szaron:

*******************

From Cat Memes:

From Jesus of the Day:

From Now That’s Wild: (I am not a fan of IPAs, especially if they’re very hoppy)

From Masih; translation from Farsi:

“What are you supporting?” Strong criticism #بهاره_هدایت of famous figures who are standing by the Islamic Republic today with their backs to the people. Bahare Hedayat bravely said that [her] estimate is that because of this interview, [s]hewill be returned to prison despite his bad physical conditions, but [s]he refused to remain silent. Shame on them for not even remaining silent and showing that they do not deserve people’s trust at every opportunity.

Hedayat is an Iranian woman’s rights activist who’s been imprisoned several times.

«از چی دارید حمایت می‌کنید؟»
انتقاد تند #بهاره_هدایت از چهره‌های سرشناس که امروز پشت به مردم، در کنار جمهوری اسلامی ایستاده‌اند.
بهاره هدایت شجاعانه گفت برآوردش این است او را به دلیل این مصاحبه، با وجود شرایط بد جسمی به زندان برمی‌گردانند اما حاضر نشد سکوت کند.
شرم بر آنها که… pic.twitter.com/9nd4qL5cdM

— Sheler Haghanifar | شلر حقانی‌فر (@ShelerHaghani) July 4, 2024

From Keith, translation from the Japanese:

[Sad news] Alpaca found looking thin and sad

It just got a haircut!

【悲報】アルパカさん、やせたかなしい姿で見つかる#ほっこりトゥイッター#アルパカ #やなせたかし pic.twitter.com/izy9ix6kXy

— 滝沢ガレソ (@tkzwgrs) July 6, 2024

From Sullivan. This is what happens when you calmly question a person who doesn’t have an answer:

Perfection. https://t.co/VqSQq2C1mJ

— Andrew Sullivan (@sullydish) April 10, 2023

Two tweets from my own feed:

Idk what this cat is going through but it’s totally a mood pic.twitter.com/hu1DJfGItR

— Why you should have a cat (@ShouldHaveCat) July 8, 2024

I didn’t know of this place:

The Crooked House of Windsor is the oldest teahouse in all of England. pic.twitter.com/gfcadtMa3L

— Giles Paley-Phillips (@eliistender10) July 7, 2024

From the Auschwitz Memorial, a French girl gassed upon arrival, age one:

8 July 1942 | A French Jewish girl, Denise Repper, was born in Paris to Alexander and Madeleine.

In December 1943 she was deported to #Auschwitz. After the selection she was murdered in a gas chamber. pic.twitter.com/bMrJPTozEF

— Auschwitz Memorial (@AuschwitzMuseum) July 8, 2024

Two tweets from Dr. Cobb. Matthew helped organize these Crick letters for the auction. Proceeds go to to the Royal Society for the Protection of Birds:

Got some money – or does your library? Original Crick letters to Peter Lawrence, including the slightly crazed 1971 letter where he announces his bonkers idea about the life coming to Earth on a spaceship, up for auction. https://t.co/2wbThCwuPx

— Matthew Cobb (@matthewcobb) July 7, 2024

As Matthew said, “This could mean trouble!”  I hope it doesn’t! The Starmers have a cat!

I look forward to welcoming the Starmer family cat JoJo to my team (the cat-inet). The fact that my new housemates are already cat-trained is excellent news. https://t.co/uCgOyL3G6z

— Larry the Cat (@Number10cat) July 7, 2024

The Netflix movie Don’t Look Up received plenty of accolades for its scarily realistic portrayal of a professor from Michigan State University attempting to warn the world about a civilization-ending asteroid impact. In reality, there are plenty of organizations in the US government and beyond whose job it is to find and avoid those impacts. And the best way to train them to do those jobs is to run scenarios and try to determine what actions would need to be taken. That was the idea behind the fifth Planetary Defense Interagency Tabletop Exercise, held at John Hopkins University Applied Physics Laboratory in April. NASA recently released a preliminary report on the results of the exercise, with a fully detailed one to come in August.

This is the fifth in a series of exercises that have been ongoing for the last eleven years. Each exercise focuses on a different scenario of a possible strike to determine what actions would need to be taken immediately or over a more extended period.

International collaborators contributed to the discussion for the first time in one of these exercises. Over 100 people participated, including representatives of the UN, UK, ESA, and JAXA. Notably absent were two other space powers—Russia and China—who would obviously impact any decision-making in a realistic scenario of an asteroid impact.

Finding asteroids before they impact us is one of the main tasks of the planetary defense community, as Fraser explains.

In this case, the scenario some participants developed didn’t directly impact China or Russia. However, both could have been affected by a tidal wave if the target asteroid had landed in the Pacific Ocean. The scenario called for an asteroid a few hundred meters across that had a 72% chance of impacting the Earth in about 14 years. 

The projected path that the asteroid carved across the Earth went from the Pacific across northern Mexico and the southern US, passing directly over Dallas and Washington DC before crossing over the Atlantic Ocean, passing over Portugal, Spain (including Madrid), and northern Africa. It was probably not lost on participants that this scenario could directly affect the town they were sitting in.

Calculations showed that there was a 45% chance the impact wouldn’t affect anybody, a relatively high chance it would impact between 1,000 and 100,000 people, and a .04% chance it would impact more than 10 million people—for example, if it scored a direct hit on the Dallas metropolitan area. That uncertainty and the extended timeline gave the planetary defense officials the most significant trouble for this exercise.

Stopping a potentially hazardous asteroid comes with its own challenges, as Fraser discusses in this video.

As in Don’t Look Up, political considerations played the forefront in the participant’s minds. Many repeated the sentiment of one anonymous participant reported in the preliminary report: “I know what I would prefer [to do], but Congress will tell us to wait.” The uncertainty about impact, and especially about whether it would affect anyone at all, was a significant consideration. In the scenario, the asteroid passed behind the Sun, so additional observations to clarify those estimates weren’t possible for another seven months. 

The availability of resources was again a primary consideration, both to track the potential impactor closely enough and to design and execute a mission to potentially deflect it. Participants didn’t believe there would be enough resources for either task and stated that it was one of their main concerns in the future. 

They also agreed that the tabletop exercise was a massive success, with it allowing decision-makers who would be involved in an actual process of determining what to do with a potential real asteroid strike to think through the steps they would have to take and what the likely political and public responses would be. Plans for additional exercises are already in the works, and the final report of the session is due to be released on August 5th, with specific assignable action items to come as part of it. While any expected asteroid impact isn’t foreseen in the coming decades, these sorts of exercises will continue to hone what is arguably one of the most valuable skills of any space agency – how to protect ourselves from one of our biggest threats.

Learn More:
NASA – Quick-Look Report – Planetary Defense Interagency Tabletop Exercise 5
NASA – NASA Asteroid Experts Create Hypothetical Impact Scenario for Exercise
UT – Another Asteroid Discovered Hours Before it Impacts the Earth
UT – If You’re Trying to Prevent an Asteroid Impact, the Technical and Political Challenges are Staggering

Lead Image:
This artist’s concept depicts an asteroid drifting through space. Many such objects frequency pass Earth. To help prepare for the discovery of one with a chance of impacting our planet, NASA leads regular exercises to figure out how the international community could respond to such a threat.
Credit – NASA / JPL-Caltech

The post NASA Imagines a Catastrophic Asteroid Impact to Study How to Prevent it appeared first on Universe Today.

The magnificent tree frog (Litoria splendida) is normally a vibrant green, but conservationists in Australia have spotted a blue-skinned individual

Not only is the entire wellness industry BS, it exists because of people who are especially gullible.

An artificial sports pitch that stores water below the surface cools itself down on hot days by letting water evaporate, just like natural grass

Through the Artemis Program, NASA will return astronauts to the lunar surface for the first time since Apollo 17 landed in 1972. Beyond this historic mission, scheduled for September 2026, NASA plans to establish the infrastructure that will enable annual missions to the Moon, eventually leading to a permanent human presence there. As we addressed in a previous article, this will lead to a huge demand for cargo delivery systems that meet the logistical, scientific, and technical requirements of crews engaged in exploration.

Beyond this capacity for delivering crews and cargo, there is also the need for transportation systems that will address logistical needs and assist in exploration efforts. These requirements were outlined in a 2024 Moon to Mars Architecture white paper titled “Lunar Mobility Drivers and Needs.” Picking up from the concurrently-released “Lunar Surface Cargo,” this whitepaper addresses the need for lunar infrastructure that will enable the movement of astronauts and payloads from landing sites to where they are needed the most. As usual, they identified a critical gap between the current capabilities and what is to be expected.

Once again, the authors cite the need for mobility systems in keeping with NASA’s objectives, as detailed in the Moon to Mars Architecture Definition Document (ADD). As they indicate, recent analyses of integrated surface operations have highlighted the importance of transportation systems that can move cargo from points of delivery to points of use across the lunar surface. This could range from “crew logistics and consumables to science and technology demonstrations, to large-scale infrastructure that requires precision relocation.”

Artist’s illustration of the new spacesuit NASA is designing for Artemis astronauts. It’s called the xEMU,, or Exploration Extravehicular Mobility Unit. Credit: NASA

In short, in addition to landers capable of delivering crews, supplies, experiments, and habitats, NASA’s Moon to Mars program also requires vehicles and support networks that can deliver them from point A to point B. As they state, the currently defined mobility elements are either primarily for crew use or are limited in mobility. This includes elements like the Lunar Terrain Vehicle (LTV) and the Pressurized Rover (PR) – which are elements of the Artemis Base Camp – and robotic missions contracted through the Commercial Lunar Payload Services (CLPS) program.

In addition, the needs and challenges that will emerge as the Artemis Program unfolds are broken down into three segments: Human Lunar Return (HLR), Foundational Exploration (FE), and Sustained Lunar Evolution (SLR). The HLR segment includes the Artemis III mission, currently scheduled for September 2026, where a crew of two will land on the lunar surface using a Starship HLS. The FE segment will coincide with Artemis IV and Artemis V (2028 and 2030), where crew sizes will expand from two to four, and the necessary infrastructure will expand.

After that, during the SLR segment, NASA plans to mount a mission a year and establish a permanent lunar habitat. Throughout this period, the demands for payloads and transportation systems will exceed current capabilities, limited to 15,000 kg (33,070 lbs) of cargo. Similar to what NASA related in their Lunar Surface Cargo whitepaper, accomplishing key mission objectives will require cargo of sizes and masses beyond these capabilities, creating the need for additional solutions.

Separation and Transportation

As the authors state, a major issue on the lunar surface affecting mobility is the need for separation between landing sites and points of use. This separation is motivated by several factors, including science objectives, lighting conditions, and safety considerations. In short, crew vehicles, habitats, and key infrastructure will be positioned at a distance from landing sites so as not to be affected by darkness caused by the landers’ shadow, contamination by the landers, and regolith or blast ejecta created by engine plumes. Based on the level of concern, separation distances are broken down into three tiers:

• Separation from lander shadowing (tens of meters; tens of yards)
• Lander blast ejecta constraints due either to separation between the lander and existing infrastructure or lander ascent (>1,000 m; ~1090 yards)
• Support for aggregation of elements in ideal habitation zones from available regional landing areas
  (up to 5,000 m; ~5470 yards)

In addition, NASA’s Moon to Mars mission architecture emphasizes the need for In-Situ Resource Utilization (ISRU), such as water ice, regolith, and minerals. NASA also recognizes the need to select habitation and hibernation sites that minimize the exposure to darkness from shadows caused by the local topography and the inclination of the Sun during lunar nights (which last two weeks at a time). This is easiest at higher elevations and on top of crater ridges. This necessitates two things:

• Exploration, habitation, and power sites will need to be located far from landing and ISRU sites
• Traverses from landing to habitation zones could encounter slopes of up to 20 degrees

As the authors state, these overlapping challenges can be met by ensuring systems are in place so mission elements can move away from landers once they are deployed on the surface:

“This could be done using independent or integrated mobility systems. The frequency of traverses between downslope and upslope locations would be driven by the cadence with which landers deliver cargo to the lunar surface and the mass that a given mobility system can carry on each traversal. Integrated architecture operations will necessitate non-trivial relocation and aggregation ranges for cargo and assets.”

Transport Capabilities

During the FE segment of the Artemis Program, NASA plans to expand surface crews from two to four, which will need to operate on the surface for about 30 days. This will require a wide range of mobility needs that can accommodate payloads of varying size and mass and over a range of distances. These include:

• Smaller technology demonstrations: 500 to 2000 kg (~1100 to 4410 lbs)
• Logistic Elements per crewed surface mission: 2,000 to 6,000 kg (~4410 to 13,230 lbs)
• Habitation Systems: 12,000 to 15,000 kg (~26455 to 33,070 lbs)

The authors acknowledge that current mobility elements could provide some cargo relocation capabilities – the LTV, for example, can accommodate 800 kg (~1764 lbs) of cargo when uncrewed. However, according to the NASA team’s analysis, the mobility capacity falls short of demand by 1,000 to 15,000 kg (2,200 to 33,070 lbs) per asset for ranges of 50 to 5,000 m (~55 to 5470 yards). Moreover, the “frequency of relocation needs” (i.e., how often payloads need to be moved) will vary considerably, ranging from single operations for large elements to multiple trips a year for containers and smaller cargo.

Mobility demand forecast ranges compared to LTV and LRV transport capabilities. Credit: NASA Conditions

The authors also address how lunar conditions are important when developing mobility systems. One of the greatest hazards on the Moon is regolith (aka. “moondust”), the fine silicate powder that covers much of the surface and sticks to everything it comes into contact with. There are lighting conditions where parts of the South Pole region will be shadowed due to the inclination of the Sun and permanently shadowed regions (PSRs) that experience perpetual darkness. Last is the matter of the terrain, which can be rocky or covered by 1 to 10 m (3.3 to 33 ft) of regolith and where slopes of more than 10 degrees are common.

This combination of factors, they argue, “creates a significant technological gap between existing systems and mobility demands for future exploration.” For starters, energy systems must provide enough power so vehicles can maintain sufficient speeds and carrying capacity and can operate during lunar nights. The authors also recommend conducting more studies on regolith mitigation strategies to prevent wear and tear and the effects regolith could have on electro-mechanical systems. They also stress the need for sufficient autonomy and/or teleoperation, allowing greater flexibility and range.

These autonomous systems must contend with the challenging lunar terrain, map the local topography, recognize obstacles and unpassable regions, and identify optimal pathways to reach their destinations. As the authors note, these systems could offer increased flexibility for mission planning and increase the speed of mobile assets, especially in areas where the terrain interferes with communications and makes remote operations impossible.

In summary, the “Lunar Mobility Drivers and Needs” whitepaper identifies some robust requirements for creating a permanent human presence on the Moon. This will entail moving cargo and assets across the lunar surface from landing sites to destinations 5 to 5,000 meters (~5.5 to 5470 yards) away. It must also be able to accommodate payloads of up to 12,000 kg or more, which is significantly higher than the current capabilities of the proposed LTV – 800 kg (~1765 lbs).

Artist rendering of an Artemis astronaut exploring the Moon’s surface during a future mission. Credit: NASA

In addition, the paper indicates that energy and environmental considerations are crucial to the design process. It is not simply a matter of scaling up small-scale mobility systems to create large-scale ones. Lastly, the computer systems and software running future mobility systems will need to be interoperable, exchanging information between vehicles and base sites, and have the ability to function autonomously or semi-autonomously.

Like the “Lunar Surface Cargo,” these findings will be explored in more detail with the 2024 Architecture Concept Review (2024 ACR), which will be released later this year, along with white papers describing NASA’s cargo return needs and lunar surface strategy.

Further Reading: NASA

The post A Moon Base Will Need a Transport System appeared first on Universe Today.

Planes flying into one of the world's busiest airports are ingesting around 10kg of dust per 1,000 flights.

Ten million new cases of dementia are diagnosed each year but the presence of different dementia forms and overlapping symptoms can complicate diagnosis and delivery of effective treatments. Now researchers have developed an AI tool that can diagnose ten different types of dementia such as vascular dementia, Lewy body dementia, and frontotemporal dementia, even if they co-occur.

New research predicts significant shifts in marine fish communities in the North Atlantic and Arctic Oceans as a result of climate warming.

Is it possible to create a new class of materials from very different substances using the 'one-pot synthesis' approach? Chemists explain how they enable the synthesis of such novel materials.

The use of certain substances in batteries is polluting air and water.

An exoplanet infamous for its deadly weather has been hiding another bizarre feature -- it reeks of rotten eggs, according to a new study of data from the James Webb Space Telescope.