Each Starship launch has the same payload as three B-52s

Wednesday, August 31st, 2022

Recent talk about hypersonic missiles got me wondering whether SpaceX’s reusable rockets would lend themselves to this role. Austin Vernon suggests that SpaceX’s Starship is America’s Secret Weapon:

B-52s flying from Barksdale AFB to complete a mission in East Asia incur a marginal cost of $50/kg to deliver bombs. Starship’s cost is cheaper and can put weapons on target in less than thirty minutes. Each Starship launch has the same payload as three B-52s.

[…]

The supply line would be a natural gas pipeline and a rail line providing fuel and projectiles to a domestic launchpad instead of ships crossing oceans.

I hadn’t considered this though:

Orbital weapons still need intelligence to tell them where to go. Starship’s sister system, StarLink, provides an answer. StarLink is a constellation of thousands of small Low Earth Orbit satellites that gives customers low latency broadband internet. It uses sophisticated phased-array radios that allow ground terminals to track satellites traveling thousands of miles per hour.

As Casey Handmer points out, StarLink can use its radios to do high fidelity synthetic aperture radar (SAR). SAR is already one of the primary ways militaries find enemy ships, and researchers have used it to track planes. It could also see ground vehicles.

While the US already has satellites capable of doing this, they are expensive and limited in number. Individual StarLink satellites cost a few hundred thousand apiece to build and launch on Starship. One of the first things China would do in war is shoot down our military satellites with anti-satellite missiles. That is a problem with bespoke satellites but not with Starlink. Anti-Satellite missiles cost tens of millions of dollars. Each Starship launch could drop off hundred of StarLink satellites. The Chinese would have to expend incredible resources to keep StarLink offline.

A satellite constellation provides other bonuses. Our GPS satellites are both hard to replace and sensitive to jamming. StarLink can provide GPS coordinates (with a few meters less accuracy), and its phased array radios make it difficult to jam.

The upshot is StarLink gives the US survivable sensing, communication, and navigation capabilities.

The military can’t afford iPhone-level software

Tuesday, August 30th, 2022

As consumers, we are spoiled by how easy our phones are to use, Austin Vernon notes, and critics expect the military to have software as capable as our phones:

If you examine the numbers, it quickly becomes apparent that the military can’t afford iPhone-level software. Apple, Google, Microsoft, and Facebook had combined operating expenses of over $600 billion in 2021. The military’s total budget is around $750 billion.

The mass of all the physical products these companies sell is probably less than one Ford-class aircraft carrier, and the number of SKUs is relatively limited. And remember, a defining feature of the software business is that marginal cost is near zero. It costs about the same to design high-quality software for 100 F-35s as for 200 million copies of the plane.

Grids have excess capacity 95% of the time

Monday, August 29th, 2022

There are many ways Texas’s grid could have avoided disaster during winter storm Uri:

Being synchronized to one of the other wide-area grids in the US is one way. Another is not to have ~50% of its households rely on electric heat.

Cold weather causes demand to spike while also hampering supply. ERCOT is not the only grid to have suffered significant supply outages during cold weather. But other grids like PJM in 2014 were bailed out by imports and lower shares of customers using electric heating.

Customers using electric heat don’t pay the costs of their impact on the grid when they only pay a fixed price per kilowatt-hour. Electric resistance heaters and air source heat pumps see power usage spike dramatically during the coldest events. The overall kilowatt-hour usage only sees a slight increase on the monthly bill, but the peak power might be two or three times higher than the norm.

Orcas attack boats off coast of Spain and Portugal

Sunday, August 28th, 2022

There is no record of an orca killing a human in the wild, but orcas are now attacking boats off the coast of Spain and Portugal:

Still, two boats were reportedly sunk by orcas off the coast of Portugal last month, in the worst such encounter since authorities have tracked them.

The incident involving the Storksons is an outlier, says Renaud de Stephanis, president and coordinator at CIRCE Conservación Information and Research, a cetacean research group based in Spain. It was farther north — nowhere near the Strait of Gibraltar, nor the coast of Portugal or Spain, where other such reports have originated.

That is a conundrum. Up to now, scientists have assumed that only a few animals are involved in these encounters and that they are all from the same pod, de Stephanis says.

[…]

Scientists hypothesize that orcas like the water pressure produced by a boat’s propeller. “What we think is that they’re asking to have the propeller in the face,” de Stephanis says. So, when they encounter a sailboat that isn’t running its engine, “they get kind of frustrated and that’s why they break the rudder.”

[…]

The population of orcas along the Spanish and Portuguese coasts is quite small. Scientists believe that the damage to boats is being done by just a few juvenile males, says Jared Towers, the director of Bay Cetology, a research organization in British Columbia.

[…]

Towers points out that such “games” tend to go in and out of fashion in orca society. For example, right now in a population he studies in the Pacific, “we have juvenile males who … often interact with prawn and crab traps,” he says. “That’s just been a fad for a few years.”

Back in the 1990s, for some orcas in the Pacific, something else was in vogue. “They’d kill fish and just swim around with this fish on their head,” Towers says. “We just don’t see that anymore.”

The act of paying lip service while concealing secret opposition

Saturday, August 27th, 2022

A fellow traveler quipped that it must be a credit to our ketman that we have survived this long, and I was shocked to realize that I’d never mentioned the term on this blog:

The Captive Mind was written soon after the author’s defection from Stalinist Poland in 1951. In it, Milosz drew upon his experiences as an illegal author during the Nazi Occupation and of being a member of the ruling class of the postwar People’s Republic of Poland. The book attempts to explain the allure of Stalinism to intellectuals, its adherents’ thought processes, and the existence of both dissent and collaboration within the postwar Soviet Bloc. Milosz described that he wrote the book “under great inner conflict”.

Chapter I: The Pill of Murti-Bing
The book begins with a discussion of the dystopian novel Insatiability by Stanislaw Ignacy Witkiewicz. In the novel, a new Mongol Empire conquers Poland and introduces Murti-Bing pills as a cure for independent thought. At first, the pills create contentment and blind obedience, but ultimately lead those taking them to develop dual personalities. Milosz compares the pills to the intellectually deadening effects of Marxism-Leninism in the USSR and the Soviet Bloc.

Chapter II: Looking to the West
Milosz describes how Western democracies were perceived with a mixture of contempt and fascination by Stalinist Central and Eastern Europe among intellectuals. Constraints put on politicians and policemen by the rule of law struck them as incomprehensible and inferior to the police states of the Communist world. Milosz noted, however, that the same intellectuals who denounced Western consumerism in print would often read Western literature in search of something more worthy than in books published behind the Iron Curtain.

Chapter III: Ketman
This chapter draws upon the writings of Arthur de Gobineau, a 19th-century French diplomat assigned to present-day Iran. In his Religions and Philosophies of Central Asia, Gobineau describes the practice of Ketman, the act of paying lip service to Islam while concealing secret opposition. Describing the practice as widespread throughout the Islamic World, Gobineau quotes one of his informants as saying, “There is not a single true Moslem in Persia.” Gobineau further describes the use of Ketman to secretly spread heterodox views to people who believe that they are being taught Islamic orthodoxy.

The new catalyst has three different active sites for the reaction

Friday, August 26th, 2022

A research team led by Prof. Minhua Shao from the Department of Chemical and Biological Engineering at HKUST, has discovered a new fuel-cell catalyst to replace pure platinum:

It not only cuts down the proportion of platinum used by 80 percent, but it also set a record in terms of the cell’s durability level.

Despite a low portion of platinum, the new hybrid catalyst developed by the research team managed to maintain the platinum catalytic activity at 97% after 100,000 cycles of accelerated stress test, compared to the current catalyst which normally sees a drop of over 50% in performance after just 30,000 cycles. In another test, the new fuel cell did not show any performance decay after operating for 200 hours.

One reason behind such outstanding performance was the fact that the new catalyst has three different active sites for the reaction, instead of just one in current catalysts. Using a formula containing atomically dispersed platinum, iron single atoms, and platinum-iron nanoparticles, the new mix accelerates the reaction rate and achieves a catalytic activity 3.7 times higher than the platinum itself. Theoretically, the higher the catalytic activity, the greater the power it delivers.

Zombie fly fungus lures healthy male flies to mate with female corpses

Thursday, August 25th, 2022

Entomophthora muscae is a widespread, pathogenic fungus that survives by infecting common houseflies with its deadly spores — and that’s when things really start to swing:

After having infected a female fly with its spores, the fungus spreads until its host has slowly been consumed alive from within. After roughly six days, the fungus takes over the behavior of the female fly and forces it to the highest point, whether upon vegetation or a wall, where the fly then dies. When the fungus has killed the zombie female, it begins to release chemical signals known as sesquiterpenes.

“The chemical signals act as pheromones that bewitch male flies and cause an incredible urge for them to mate with lifeless female carcasses,” explains Henrik H. De Fine Licht, an associate professor at the University of Copenhagen’s Department of Environment and Plant Sciences and one of the study’s authors.

As male flies copulate with dead females, the fungal spores are showered onto the males, who then suffer the same gruesome fate.

The Rotating Detonation Engine is an extension of the Pulse Detonation Engine, which is an extension of The Pulse Jet Engine

Wednesday, August 24th, 2022

The concept behind rotation detonation engines dates back to the 1950s:

In the United States, Arthur Nicholls, a professor emeritus of aerospace engineering at the University of Michigan, was among the first to attempt to develop a working RDE design.

In some ways, a Rotating Detonation Engine is an extension of the concept behind pulse detonation engines (PDEs), which are, in themselves, an extension of pulsejets. That might seem confusing (and maybe it is), but we’ll break it down.

Pulsejet engines work by mixing air and fuel within a combustion chamber and then igniting the mixture to fire out of a nozzle in rapid pulses, rather than under consistent combustion like you might find in other jet engines.

In pulsejet engines, as in nearly all combustion engines, igniting and burning the air/fuel mixture is called deflagration, which basically means heating a substance until it burns away rapidly, but at subsonic speeds.

A pulse detonation engine works similarly, but instead of leveraging deflagration, it uses detonation. At a fundamental level, detonation is a lot like it sounds: an explosion.

While deflagration speaks to the ignition and subsonic burning of the air/fuel mixture, detonation is supersonic. When the air and fuel are mixed in a pulse detonation engine, they’re ignited, creating deflagration like in any other combustion engine. However, within the longer exhaust tube, a powerful pressure wave compresses the unburnt fuel ahead of the ignition, heating it above ignition temperature in what is known as the deflagration-to-detonation transition (DDT). In other words, rather than burning through the fuel rapidly, it detonates, producing more thrust from the same amount of fuel; an explosion, rather than a rapid burn.

The detonations still occur in pulses, like in a pulsejet, but a pulse detonation engine is capable of propelling a vehicle to higher speeds, believed to be around Mach 5. Because detonation releases more energy than deflagration, detonation engines are more efficient — producing more thrust with less fuel, allowing for lighter loads and greater ranges.

The detonation shockwave travels significantly faster than the deflagration wave leveraged by today’s jet engines, Trimble explained: up to 2,000 meters per second (4,475 miles per hour) compared to 10 meters per second from deflagration.

[...]

A rotating detonation engine takes this concept to the next level. Rather than having the detonation wave travel out the back of the aircraft as propulsion, it travels around a circular channel within the engine itself.

Fuel and oxidizers are added to the channel through small holes, which are then struck and ignited by the rapidly circling detonation wave. The result is an engine that produces continuous thrust, rather than thrust in pulses, while still offering the improved efficiency of a detonation engine. Many rotation detonation engines have more than one detonation wave circling the chamber at the same time.

As Trimble explains, RDEs see pressure increase during detonation, whereas traditional jet engines see a total pressure loss during combustion, offering greater efficiency. In fact, rotation detonation engines are even more efficient than pulse detonation engines, which need the combustion chamber to be purged and refilled for each pulse.

[...]

According to the Air Force Research Lab, RDE technology could make high-speed weapons much more affordable, which is of particular import following a recent Defense Department analysis that indicated the hypersonic (Mach 5+) weapons in development for the Air Force may cost as much as $106 million each.

Long-term low-dose alcohol intake promotes white adipose tissue browning and reduces obesity

Tuesday, August 23rd, 2022

There are numerous pieces of evidence indicating that moderate alcohol intake has a protective effect on metabolic diseases:

Our previous studies revealed that long-term low-dose alcohol intake resists high-fat diet (HFD) induced obesity. A process in which white adipose tissue can be stimulated and turned into heat-producing brown adipose tissue named white adipose browning is associated with energy expenditure and weight loss. In this study we aimed to investigate whether alcohol causes the browning of white adipose tissue and whether the browning of white adipose tissue is involved in the resistance to the occurrence of obesity caused by long-term low-dose alcohol intake. After eight months of alcohol feeding, the body weight of mice had no significant change, but the fat content and lipid deposition in the liver were reduced. Morphological observations revealed that the browning of white adipose tissue occurred.

[...]

Moderate alcohol drinking mice had faster lipid metabolism and slower lipid anabolism. In addition, we found that long-term low-dose alcohol intake prevented the increase of body weight, triglycerides, inflammation and energy expenditure decrease induced by HFD. Moderate alcohol consumption increased the expression of UCP1 and glucose uptake in the adipose tissue of the HFD group. In conclusion, our results show for the first time that alcohol can trigger the browning of white adipose tissue to counteract obesity.

Our legal system doesn’t seem designed for thwarted attacks

Monday, August 22nd, 2022

Our legal system doesn’t seem designed for thwarted attacks:

The Grant County Sheriff’s Office said in a news release on Facebook deputies were called around 9 p.m. Friday when concertgoers at the Gorge Amphitheater witnessed the man, 31-year-old Jonathan R. Moody, inhale an intoxicant before loading two 9 mm pistols in the parking lot.

Police estimated upward of 25,000 people were at the amphitheater for an electronic dance music festival. Moody allegedly was asking concertgoers what time the event ended and where people would exit the venue.

Moody was arrested on suspicion of one count of possession of a dangerous weapon and one count of unlawful carrying or handling of a weapon. He never entered the amphitheater, police said, and nobody was injured.

The owner can by right operate a bar, a restaurant, a boutique, a small workshop on the ground floor

Monday, August 22nd, 2022

There are a number of reasons small business in Tokyo is so vibrant:

A huge one that you can look at cities around the world and ask is how many flexible microspaces are available across your city. By microspaces, I mean small little nooks and crannies in the commercial or residential sectors of the city that you can do a lot of different things with and don’t need to pay a huge amount of money in rent.

This is going to sound wild to anyone who lives in the US, but for any two-story rowhouse in Tokyo, the owner can by right operate a bar, a restaurant, a boutique, a small workshop on the ground floor — even in the most residential zoned sections of the city. That means you have an incredible supply of potential microspaces. Any elderly homeowner could decide to rent out the bottom floor of their place to some young kid who wants to start a coffee shop, for example. When you look at what we call yokocho alleyways — charming, dingy alleyways that grew out of the black markets post-World War II, which are some of the the most iconic and beloved sections of the city now — it’s all of these tiny little bars and restaurants just crammed into every available space.

[...]

Liquor licenses are extremely cheap and easy. A liquor license in an American city can sometimes run up to $500,000. You’re not going to have a little four-seat, mom-and-pop bar for the locals. So those regulatory and policy choices that we make fundamentally determine what our cities are going to feel like.

It is descended from bipedal dinosaurs

Sunday, August 21st, 2022

Ostriches, unlike humans, can run very fast on two legs:

Their legs are all bone and tendon. They don’t have any muscles in their legs or feet. All the muscles are up in the body. It allows their legs to go faster — ostriches can run 45 miles an hour.

A human foot has 26 individual bones in it. And you have two feet, so you have 52 foot bones. That means a quarter of your skeleton is made of foot bones. Tons and tons of foot bones.

[...]

We are primates, and primates live in trees. And in trees, you need a mobile foot. Think about an orangutan’s foot, a chimpanzee’s foot. They can use their foot in the same way that I use my hand to grab onto things.

The bones that we have in our foot are the exact same 26 bones that a chimpanzee has. They’re just tweaked a little bit, and that converts our foot from a grasping organ, like a chimpanzee’s, into one that can push off the ground. But we still have those 26 individual bones. And what are the results? Well, you get plantar fasciitis, you get an ankle sprain.

[...]

Think about the ostrich lineage. It doesn’t come from an ape or a primate. It is descended from bipedal dinosaurs. The bones of their ancestors’ feet have fused together into a single, rigid column. They only have eight bones in their feet, so there’s less capacity for motion. Instead, their foot looks a lot like the Paralympic prosthetic blade that athletes use with that single rigid structure that can hit the ground, store elastic energy and then push off the ground and propel them into their next step.

Building regulations have made cities far more susceptible to heat

Saturday, August 20th, 2022

Building regulations in the developed world, especially the United States, have made cities far more susceptible to heat, Connor Harris explains:

And this is just one instance of a broader lesson: regulations can hurt the environment just as easily, or even perhaps more easily, than they can help.

I live in Houston, the most notoriously hot and humid large city in the United States, in an intensively redeveloped prewar residential neighborhood that comprises mostly mid-rise apartment blocks and three-story townhouses. Even Houston’s summer heat is quite comfortable in most circumstances. I have never felt overheated while eating lunch outdoors on a shaded patio, for example, or even after mid-afternoon bicycle trips along local roads or walks along shaded sidewalks and park trails.

Houston heat is made intolerable by the city’s vast quantity of heat-absorbing asphalt and the frequent lack of shade. I frequent a few restaurants a short distance from my apartment, in strip malls off of a busy, six-lane arterial road. The walk from my apartment to the restaurant, along an unshaded sidewalk between the road on one side and the parking lots of the strip malls on the other, is far more uncomfortable than even exercise in the shade at the same temperature. Even a short one-minute walk through a big-box store’s parking lot can be almost intolerable and make the air conditioning inside feel almost life-saving. More rigorous research confirms that large parking lots contribute powerfully to the urban heat island effect. It’s no wonder that anyone whose experience of the Texas outdoors involves mostly walking between cars and commercial buildings would find the heat oppressive.

These aspects of Houston’s built environment owe less to the workings of the free market than to a set of market-distorting land-use regulations that sacrifice heat resilience, while also wasting large amounts of valuable land, in the name of giving motorists maximum possible convenience. In these respects, Houston’s land-use regulations are perfectly ordinary. Most prominent are the massive requirements for off-street parking spaces for almost all types of development outside a few downtown areas. In Houston, even studio apartments, seldom occupied by more than one person, require 1.25 parking spaces. Any commercial development requires far more parking space. Supermarkets, for example, require five parking spots per 1,000 square feet of floor area. Bars and restaurants, depending on classification, can require up to 14. A typical parking spot takes up about 300 square feet of space, so such establishments could need four times the amount of land for parking lots as for their building itself. Many commercial parking lots often sit mostly empty.

Other common aspects of American land-use codes, such as setbacks and traffic engineering standards, also make heat in American cities harder to bear. Old cities in hot regions such as Latin America and the Middle East typically have buildings (which often incorporate colonnade walkways) set close to the street to provide shade for pedestrians—an eminently sensible design specifically prohibited by most American zoning codes, which enforce a suburban appearance on residential neighborhoods by requiring “front setbacks,” or wide margins of land along the street that cannot be built on. Builders typically pave over large amounts of this setback land to provide driveways much longer than they would have to be without setbacks, adding yet more hot asphalt into cities.

[...]

Traffic-engineering standards also contribute to overheated cities. Houston, for instance, mandates street widths of at least 50 feet on local roads in new subdivisions—more than four times the standard 12-foot width of an interstate highway lane. This gives enough room for cars to pass one another at speed with one lane of parking on each side of the road, a massive waste of land and asphalt in residential areas with plentiful off-street parking where, even at rush hour, local roads will see at most a few cars per minute. It’s common traffic-engineering practice, as well, to maintain the sides of major roads as “clear zones” free from trees and other fixed obstacles, in order to limit the damage to cars that run off the side of the road. This practice eliminates shade while providing only doubtful safety benefits.

Living in walkable neighborhoods alone does not do the job

Friday, August 19th, 2022

There was a viral tweet recently saying something like “Americans only obsess over college so much because it’s the only time they get to live in a walkable neighborhood,” and Ben Southwood thinks there’s something to this:

But living in walkable neighbourhoods alone does not do the job. Most Americans do not choose to live in walkable neighbourhoods, developers do not maximise profits by building walkable neighbourhoods, and walkable neighbourhoods don’t usually have the highest location-adjusted prices. (Though see many admirable projects trying to change this on Coby Lefkowitz’s Twitter feed.)

Americans rarely live on walkable streets. There are some very high rent neighbourhoods that are walkable &mdsah; Manhattan, Georgetown, and so on. There are bungalow courts and assisted living areas for older people. These two neighbourhood types involve clustering, based around affordability or other restrictions, and are often desirable.

Then there are trailer communities, and there are some neighbourhoods of public housing that are in some sense walkable, although the walks tend to be across bleak windswept open spaces or within poorly kept up towers and blocks. These two neighbourhood types tend not to be people’s first choice, and are generally seen as less desirable.

As will be clear if you read my first post, or the title of this very Substack, I think the reason people loved their college days so much, apart from the fact they were young and beautiful, with perfectly functioning brains and livers, is that at university one has all one’s best friends within two minutes walk. And they’re almost always free to hang out.

Compared to the small town example I looked at before, people at a given university are probably more like potential friends. Most importantly, the students all chose to be there — unlike prisoners, who also live in walkable neighbourhoods. And they chose to be there in part because of an organising feature of the university, probably making the intake similar to each other in some way, possibly fitting some cultural type.

In short: it’s also about clustering.

Grades and test scores should be top factors in college admissions

Thursday, August 18th, 2022

The U.S. public continues to think that grades and test scores should be top factors in college admissions:

More than nine-in-ten Americans (93%) say high school grades should be at least a minor factor in admissions decisions, including 61% who say they should be a major factor. Grades are, by far, the criteria the public says should most factor into admissions decisions. This is followed by standardized test scores (39% major factor, 46% minor factor) and community service involvement (19% major, 48% minor), according to a Pew Research Center survey conducted March 7-13, 2022.

Nearly half of Americans (46%) say someone being the first in their family to go to college should be either a major (18%) or minor (28%) factor in admissions decisions, while a similar share say athletic ability should factor into these decisions (9% major, 36% minor).

By comparison, nearly three-quarters of Americans or more say gender, race or ethnicity, or whether a relative attended the school should not factor into admissions decisions.

The relative importance of each of these factors is unchanged since 2019.