October 2021 Archives

Tuesday, October 19, 2021

CONTEXT: David Friedman and James Bennett on Property Rights in Space

Posted at 11:30 Permalink

THE HAPPENING WORLD: SpaceX Starship SN 20 Pre-Burner Test

This appears to have been a single engine pre-burner test of Raptor vacuum engine number 5. The pre-burner powers the turbopumps that force fuel and oxidiser into the combustion chamber. In a pre-burner test, the main combustion chamber is not ignited. This is a normal step on the way to a full thrust static firing.

Posted at 11:09 Permalink

Monday, October 18, 2021

CONTINUITY: 1915 Vintage Western Electric “Candlestick” Phone

The classic Western Electric #20B candlestick telephone was patented in 1904 and remained in production until the 1920s, when it was supplanted by desktop phones with the transmitter and receiver in one handset. The candlestick phone contained no ringer, and was connected to a separate “subscriber set” or ringer box containing the bells. Later models for automatic exchanges added a rotary dial in the base. Many candlestick phones remained in service, leased and maintained by telephone companies, until the 1940s and '50s. They are electrically compatible with today's wired telephone networks.

The earpiece that hung on the hook was called the “receiver”, and the phone was answered by picking it up. A remnant of this remains in the English language, with many people continuing to call the handset of modern telephones “the receiver”. In French, the handset is called «le combiné», indicating it contains both the microphone and receiver.

Posted at 13:55 Permalink

CONTINUITY: Fat Finger—More Than 12,000 Ethereum Lost to Typos

Unlike Bitcoin public addresses, which incorporate a 32 bit checksum, the original specification for Ethereum public addresses was simply strings of 40 hexadecimal digits, for example 0xc9b83ab54c84aac4445b56a63033db3d5b017764. If somebody attempts to send funds to such an address and accidentally mistypes or transposes even a single digit of the address, the funds will be sent to an address whose private key is unknown and which is computationally intractable to discover (there are 1640≈1048 possible Ethereum addresses) and thus lost forever. Obviously, it is a poor idea to type in such an address, and errors in optical scanning, text editors, and cut and paste mechanisms all pose risks of error.

In 2018, Johannes Pfeffer decided to estimate the quantity of Ether (the name for the currency of the Ethereum system) lost by having been sent to mistyped addresses. The methodology was clever and simple: search the blockchain for pairs of addresses, both of which had received funds, but which differed only by one character. An address of such a pair which had no outgoing transactions was almost certainly a typographical error entering the other, because the probability of two such similar addresses being generated from independent known private keys is comparable to that of guessing the private key from a public address. He reported the results in “Over 12,000 Ether Are Lost Forever Due to Typos”.

As of the date of his study, 2,674 typos were found, affecting 2,053 accounts, with total funds lost amounting to ETH 12,622, which at this writing has a value in excess of US$ 47 million (when he did his study, it was “only” US$ 8.84 million). All of these funds have gone to the great bit bucket in the sky, never to be seen again.

It's odd that Ethereum addresses weren't designed from the outset to incorporate a checksum, especially since International Bank Account Numbers (IBAN) and Bitcoin addresses which pre-date Ethereum both include checksums. The reasoning appears to have been that the hexadecimal addresses would not be directly used by humans, but rather encoded forms such as the IBAN-compatible ICAP or through a domain name like system such as now exists with the Ethereum Name Service. But, in fact, Ethereum wallets and individuals went ahead and used the hexadecimal addresses without checksums, and the consequences were predictable.

In 2016, this situation became sufficiently embarrassing that Ethereum Improvement Proposal EIP-55, “Mixed-case checksum address encoding” specified a checksum of sorts, in which a hash of the original address is encoded in hexadecimal digits between “A” and “F” by writing them in upper or lower case letters. This provides an average of 15 check bits per address, which reduces the probability of an error not being detected to 0.0247%, which is around fifty times better than the two digit IBAN checksum. Almost all Ethereum clients now express addresses in this form and check any submitted address which contains mixed case hexadecimal digits. For compatibility, however, un-checksummed addresses with uniform case hexadecimal digits continue to be accepted.

It would be interesting to repeat the typo analysis and see what effect the introduction and widespread use of checksummed addresses has had on the rate and magnitude of losses to typos.

Posted at 12:00 Permalink

CONTEXT: Magnetic Mysteries—The “Simple Magnetic Over-Unity Toy”

Ignoring potential energy is the source of much confusion and “inspiration” to designers of perpetual motion machines of the first kind. Simple experiments with magnets demonstrate how confusing and deceptive it can be when all energy flows are not accounted for. Fortunately, physicists, engineers, and patent examiners have learned to approach claims of “over unity” (something for nothing) with extreme scepticism. Now if we could just get the economists and politicians on board.

Posted at 11:32 Permalink

TRACKING WITH CLOSEUPS: A Monolithic Schmidt-Cassegrain Telescope

A Schmidt-Cassegrain telescope has multiple optical elements: a spherical primary mirror, a hyperbolic secondary mirror, a Schmidt corrector plate (aspheric lens), and sometimes a field flattener lens to create a planar image. Could you make all of these out of one solid piece of glass?

Posted at 11:19 Permalink

Sunday, October 17, 2021

CONTINUITY: On the Road with Tesla “Full Self Driving” Beta 10.2

Posted at 13:46 Permalink

CONTEXT: Melting Nuclear Waste to the Earth's Mantle

Here is the 2011 paper, “Self-Sinking Capsules to Investigate Earth’s Interior and Dispose of Radioactive Waste”. Full text is available at the ResearchGate site. The first paragraph of the paper is:

Technical experts, science fiction writers, and environmental advocates have all famously considered a self-descending spherical body in a melting environment not as a solution but as a problem. In connection with nuclear reactor core meltdown, this phenomenon is the so-called China Syndrome. Let’s step back and consider the China Syndrome as a solution.

Posted at 12:20 Permalink

TRACKING WITH CLOSEUPS: Orbiting Nothing—Lagrange Points and Halo Orbits

Posted at 12:14 Permalink

THE HAPPENING WORLD: Weekly Space Report: Mechazilla Rising, NASA to Monitor Starship Re-entry, Relativity Space 3D Printed Launcher

Posted at 11:38 Permalink

Saturday, October 16, 2021

THE HAPPENING WORLD: Rwanda Files to Operate 327,320 Satellite Constellation

Satellite Network Filing RRW2021-42537 was received on 2021-09-21 for the “CINNAMON-937” constellation, which is described in the supplementary notes [PDF] as:

An orbital shell is here defined as the set of orbits with the same inclination. There are 27 of such orbital shells. Each orbital shell, except the equatorial shell made of one single plane, has a total of 12,960 satellites. The 27 orbital shells comprise of 327,320 satellites.

Satellites are to orbit at altitudes between 550 and 643.6 km in shells arranged by inclination,

Posted at 13:49 Permalink

CONTINUITY: The Sound of Sorting: Fifteen Algorithms in Six Minutes

Sorting items into order is an important task in computing, and a great deal of intellectual effort has been put into studying various techniques optimised for different circumstances. For example, sorting a small collection of objects that fit into memory is one thing, while a huge database that spans multiple removable storage media is entirely another. An algorithm that works well for data that's initially in completely random order may not be the best for data which is mostly already sorted. Donald Knuth wrote an 800 page book on Sorting and Searching, and new work on the topic is published every year.

This video visualises the behaviour of fifteen different sorting algorithms, ranging from very good to horrific (“bogosort”), each operating on a set of random integers with a size adapted to the efficiency of the algorithm. Here is background on how the video was made. A YouTube playlist of additional sorting algorithms is available.

Posted at 13:19 Permalink

THE HAPPENING WORLD: Top Ten Assets by Market Capitalisation


The Infinite Market Cap Web site ranks more than 13,000 assets by market capitalisation, which is defined for various assets as follows.

  • For precious metals the Market Cap is calculated by multiplying the its price with an estimation of the quantity of metal that has been mined so far. These estimations are updated annually.
  • For stocks it is calculated by multiplying the amount of outstanding shares with the current share price.
  • The Market Cap of cryptocurrencies is calculated by multiplying the circulating supply with the coin's price.

One can quibble with these definitions: for example, silver, ranked as the 7th largest asset, is an industrial metal which is consumed in many of its applications, so there is a large gap between the total amount mined over history and the existing above-ground supply. For cryptocurrencies, estimates are based upon circulating supply in public hands, excluding funds believed to be lost, some of which might reappear in the future. Obviously, all of these asset prices are volatile and this ranking represents their valuation as of the date of this post.

A few observations: it is stunning to observe that, among companies in the top ten, only Saudi Aramco is not a technology company, and is the only one founded prior to 1975. We often think of Big Oil and Big Banking as archetypes of corporate wealth and power, but only one oil company and no bank made the top ten. The highest ranked bank, JPMorgan Chase, came in at 16th, just before the Ethereum cryptocurrency at 17th. The largest traditional industrial company (but with a strong presence in technology as well) was Samsung at 22, and brick and mortar retailing leader Walmart ranked 23.

The total valuation of the top ten assets combined was US$ 25.7 trillion, which is less than the U.S. national debt of US$ 28 trillion and change.

Autodesk ranks number 306, with market cap US$ 64 billion, beating out Northrop Grumman at 307 and US$ 63.3 billion and Ford Motor Company in 312th place at US$ 62.7 billion. Also in the cheap seats are Federal Express (322), UBS (324), General Dynamics (341), and Honda (381).

Dogecoin is hanging in there at 705th with market cap US$ 31.5 billion.

Posted at 12:15 Permalink

CONTEXT: A Zoologist Contemplates Alien Life

Might convergent evolution and the limited number of biomechanical solutions to the needs of life result in alien life being no more weird than what we find on Earth? (Although if you look at some of the critters that inhabit the ocean, that's already pretty weird.) Dr Kershenbaum's book is The Zoologist's Guide to the Galaxy.

Posted at 11:14 Permalink

Friday, October 15, 2021

THE HAPPENING WORLD: Shenzhou-13 Crew Launch to Chinese Tiangong Space Station

Shenzhou-13 launch is scheduled for 16:23 UTC on 2021-10-15. The launch is to carry a crew of three to the Tiangong space station for a planned six-month stay.

Posted at 14:11 Permalink

TRACKING WITH CLOSEUPS: Prelude FLNG—600,000 Tonne Floating Liquefied Natural Gas Plant

Here is more about Prelude FLNG. It is 488 metres long, 74 metres high, and rises 105 metres above the water line. Unpowered, it is towed into position by oceangoing tugboats, then tethered to the sea floor by chains and connected to well head equipment by flexible pipes. It is designed to be able to ride out a category 5 cyclone, and has the ability to “weathervane” into the wind.

Posted at 12:47 Permalink

CONTEXT: The Agoric Approach to Computing

Agoric computing is a concept of structuring computation and business systems around the model of a free market, supplanting traditional systems which often resemble top-down, centrally planned economies. It encompasses smart contracts, which are central to the emerging field of decentralised finance (DeFi), which is not entirely 100% scams and pyramid schemes, despite how it may appear. In this 42 minute long conversation, the CEO and Chief Scientist of Agoric Systems Operating Company trace the history of smart contracts back to the pioneering work at the American Information Exchange (AMIX) in the 1980s (backed by Autodesk from 1988 through 1992), describe how smart contracts are integrated with blockchain technology, and explain why they have chosen JavaScript as the language on which to build their technology.

Posted at 12:18 Permalink

THE HAPPENING WORLD: Lucy—Visiting Eight Asteroids with One Spacecraft

NASA's Lucy mission is scheduled to launch on Saturday, 2021-10-16 at 09:34 UTC. Its planned twelve-year mission will use multiple Earth gravity assists to fling it on a path through both the leading and trailing Trojan regions of Jupiter, where it will encounter seven asteroids, including some believed to date from early in the formation of the solar system. Lucy will also fly by a small main belt asteroid on its outbound trajectory. Here is a live Webcast of the launch.

Posted at 11:57 Permalink

CONTINUITY: Before GPS—The Navy Navigation Satellite System

This 1967 U.S. Navy training film describes the Transit satellite navigation system, which went into service in 1964, providing global coverage with position fixes every several hours at the equator and more frequently at higher latitudes. Its original mission was providing position information to Polaris ballistic missile submarines, and was later adopted by a wide variety of surface ships. The architecture was very different from GPS, and relied upon Doppler measurement of transmissions from a constellation of five satellites in low polar orbit. Each satellite transmitted an ephemeris of its position, updated daily from a computer centre on the ground and a network of tracking stations, from which shipboard computers could calculate position based upon the observed Doppler shift. Only one satellite was needed to provide 2D (latitude and longitude) accurate to originally 400 metres but eventually improved to around 200 metres as the system was refined. The Transit system remained in service until 1996, when it was retired in favour of the Global Positioning System (GPS), which had become fully operational (continuous global coverage) the preceding year, but since the 1980s had provided better and more frequent 3D position fixes than Transit.

Posted at 11:19 Permalink

Thursday, October 14, 2021

TRACKING WITH CLOSEUPS: Payout Mechanism from a Vintage Slot Machine

Posted at 13:55 Permalink

CONTINUITY: Fifty Years Ago—The First Commercial Video Game

Here is a game play video.

Posted at 13:22 Permalink

THE HAPPENING WORLD: Space Tourism Companies Prohibit Passengers from Selling Souvenirs

“Commercial space” for vendors, not customers.

Posted at 12:52 Permalink

CONTINUITY: How Photolithography Works—Part 6: Resolution Enhancement

The ultimate limit on the feature size photolithography can produce is set by the wavelength of the light it uses and the physics of electromagnetism, but clever device designers have invented a bag of dirty tricks to squeeze more onto a chip. The series concludes with a survey of some of these techniques, including multiple exposure and etching cycles, atomically deposited spacers, self-assembling molecules, and three-dimension stacking of transistors.

Posted at 12:05 Permalink

CONTEXT: Visiting a Server Farm in Germany

Posted at 11:38 Permalink

Wednesday, October 13, 2021

CONTEXT: What Did Dinosaurs Really Look Like?

Artist C. M. Kosemen has drawn modern animals as they might be reconstructed from their skeletons alone: “Nightmarish sketches reveal what modern animals would look like if we drew them in the same way as dinosaurs based on their skeletons”.

Posted at 14:28 Permalink

TRACKING WITH CLOSEUPS: Destructive Interference: Cancelling Light

Where does the energy go?

Posted at 14:16 Permalink

CONTEXT: Float-Through McDonald's

You'll never guess in which German city it's located.

Posted at 13:17 Permalink

CONTINUITY: James Webb Space Telescope Arrives in French Guiana

Launch on Ariane 5 flight VA256 is scheduled for December 18, 2021.

Posted at 12:02 Permalink

THE HAPPENING WORLD: Blue Origin New Shepard NS-18 Launch

The Webcast coverage is scheduled to start at 12:30 UTC on 2021-10-13.

Posted at 11:38 Permalink

Tuesday, October 12, 2021

CONTEXT: Why Do Bees Make Rhombic Dodecahedrons?

Posted at 14:39 Permalink

CONTINUITY: Why Do U.S. Power Plugs Have Those Holes in the Prongs?

The dead hand of the past meets Safetyland's electric plugs, some of the worst and most stupid in the world.

Posted at 14:16 Permalink

CONTINUITY: How Photolithography Works—Part 5: Photolithography Metrics

Photoresists (see Part 3) are highly nonlinear (or, as a photographer would say, high contrast). Getting the “dose” (or exposure) correct is critical for imaging small features, and this is a tradeoff between focus and illumination, which involves some intricate measurements and calculations.

Posted at 12:46 Permalink

TRACKING WITH CLOSEUPS: Firefly Aerospace Factory and Test Site Tour

Posted at 12:12 Permalink

Monday, October 11, 2021

CONTEXT: Linkage Mechanism Converts Binary to Decimal

Posted at 14:15 Permalink

THE HAPPENING WORLD: Attack Submarine USS Connecticut Collides with “Object”—What Happened?

Here is more about the incident at the U.S. Naval Institute Web site, “Attack Submarine USS Connecticut Suffers Underwater Collision in South China Sea”. This is the official statement by the U.S. Navy. The name of the Connecticut's captain is Bill Clinton.

Posted at 12:20 Permalink

THE HAPPENING WORLD: Tesla Rolling Out “Full Self-Driving” Beta 10.2 by “Safety Score”

SCANALYZER has previously written about Tesla's “Safety Score” spyware which monitors customers' driving behaviour and reports back to headquarters. Now it's official: customers who have paid for Tesla's so-called “Full Self-Driving” capability will receive beta test updates in descending order by safety score, with only those who have a perfect score of 100/100 in the last 100 miles receiving the update first.

Perhaps a future update will monitor their customers' body mass index based upon seat settings and a weight sensor in the driver's seat and refuse to drive to fast food restaurants if it's too high.

“They'll go into debt to buy their own shackles” — Kelvin R. Throop

Posted at 11:17 Permalink

CONTINUITY: Learning to Land the Space Shuttle—Approach and Landing Tests

Posted at 10:47 Permalink

Sunday, October 10, 2021

CONTINUITY: How Photolithography Works—Part 4: Imaging Process

How do you make an image whose feature sizes are smaller than the wavelength of light you're using? It might seem like black magic, but it's really a matter of light magic, involving a bag of dirty tricks called “Optical Proximity Correction” (OPC), which take into account the wave properties of light and construct masks which often look nothing like the image they create, but create interference patterns which form the desired features. “Think of your semiconductor wafer as a 160 gigapixel camera image sensor.”

Posted at 15:25 Permalink

TRACKING WITH CLOSEUPS: French Cuisine in Space

European Space Agency astronaut Thomas Pesquet describes food on the International Space Station, including the “crew preference food” he brought to supplement the basic fare provided by NASA. The audio is in French, with English subtitles. (If the subtitles are not automatically enabled, click the “CC” box at the bottom to turn them on.)

Posted at 14:10 Permalink

CONTEXT: Edward Snowden on “Central Bank Digital Currencies”

Central Bank Digital Currencies or, as I like to call them, “slave money”, are a hot topic among globalists and other would-be slavers. Just imagine how wonderful it will be when your government can confiscate your cash remotely with the click of a mouse, control the things on which you can spend it, or keep you from spending it entirely if you have done something of which they disapprove. I have been warning about this ever since my “Unicard: Ubiquitous Computation, Global Connectivity, and the End of Privacy” paper in 1994, which was considered dystopian science fiction at the time.

In a few years, countries that aspire to economically enslave their populations won't even have to develop their own systems for doing so—they'll be able to buy it off the shelf as a turnkey system from China, integrated with the “social credit” system.

Posted at 12:34 Permalink

THE HAPPENING WORLD: Weekly Space Report: Starbase Developments, 33 Raptor Super Duper Heavy, Amazing 3D Raptor Model, Ingenuity Grounded

Posted at 11:20 Permalink

Saturday, October 9, 2021

CONTINUITY: Boeing Starliner OFT-2 “Hangar Queen”—One Valve Still Stuck, “Working Toward Launch Opportunities in the First Half of 2022 “

Posted at 14:45 Permalink

CONTEXT: How Virtual Worlds Work—Part 3, Digital Objects

Posted at 12:49 Permalink

CONTINUITY: SpaceX Completes Secondary Share Offering at Valuation of US$ 100.3 Billion

Posted at 12:08 Permalink

TRACKING WITH CLOSEUPS: The Schmid Peoplemover

Posted at 11:28 Permalink

Friday, October 8, 2021

THE HAPPENING WORLD: Elon Musk at the 2021 Tesla Annual Shareholder Meeting

“Over time, you'll see all manufacturers will make electric vehicles, and eventually all manufacturers will make autonomous vehicles. Tesla is open to licensing autonomy.

“… you can recycle battery materials. You can think of batteries as essentially high grade ore. So you can get your lithium and your nickel … from rocks or from batteries. It's much better to get them from batteries.”

Posted at 14:52 Permalink

CONTEXT: “Slowed Canonical Progress in Large Fields of Science”


In many academic fields, the number of papers published each year has increased significantly over time. Policy measures aim to increase the quantity of scientists, research funding, and scientific output, which is measured by the number of papers produced. These quantitative metrics determine the career trajectories of scholars and evaluations of academic departments, institutions, and nations. Whether and how these increases in the numbers of scientists and papers translate into advances in knowledge is unclear, however. Here, we first lay out a theoretical argument for why too many papers published each year in a field can lead to stagnation rather than advance. The deluge of new papers may deprive reviewers and readers the cognitive slack required to fully recognize and understand novel ideas. Competition among many new ideas may prevent the gradual accumulation of focused attention on a promising new idea. Then, we show data supporting the predictions of this theory. When the number of papers published per year in a scientific field grows large, citations flow disproportionately to already well-cited papers; the list of most-cited papers ossifies; new papers are unlikely to ever become highly cited, and when they do, it is not through a gradual, cumulative process of attention gathering; and newly published papers become unlikely to disrupt existing work. These findings suggest that the progress of large scientific fields may be slowed, trapped in existing canon. Policy measures shifting how scientific work is produced, disseminated, consumed, and rewarded may be called for to push fields into new, more fertile areas of study.

Here is the full paper, “Slowed canonical progress in large fields of science”. I repeat my frequent observation, “Once Pareto gets into your head, you'll never get him out.”

Posted at 14:06 Permalink

CONTINUITY: How Photolithography Works—Part 3: Photoresist

Photoresist is the “secret sauce” of microelectronics. It is a chemical coating which, applied to a silicon wafer, is rendered soluble or insoluble by exposure to light. Post-exposure, the soluble part is washed away, leaving a mask which protects portions of the chip not to be affected by the next processing step. This sounds simple, but achieving nanometre resolution and avoiding optical distortion are formidable challenges which have been surmounted as device geometries shrink.

Posted at 13:06 Permalink

TRACKING WITH CLOSEUPS: “Never Mind”—“Gamma Ray Burst” From Remote Galaxy Turns Out To Be Flash From Space Junk

Detection of an apparent gamma ray burst in the act of occurring in a galaxy at redshift 11, indicating we are observing it as it was just 420 million years after the big bang was reported in the paper “A possible bright ultraviolet flash from a galaxy at redshift z ~ 11” in December 2020. “Not so fast” responded other astronomers, in the paper “A more probable explanation for a continuum flash in the direction of a redshift ≈ 11 galaxy” and elsewhere, pointing out the extreme improbability of such an observation and the far more likely explanation that it was a transient due to reflection from an orbiting satellite or space junk. Now the case has been closed with the publication of “GN-z11-flash was a signal from a man-made satellite not a gamma-ray burst at redshift 11” which identifies the flash as a glint of sunlight from a derelict Breeze-M upper stage from a Russian Proton rocket in a highly elliptical orbit.

Posted at 12:14 Permalink

CONTINUITY: Apollo Spacecraft S Band Communication System, Part 2

Communications from the Apollo spacecraft to ground stations were via an S band microwave link with a radiated power of 11.6 watts. The signal sent to the antenna was produced by the transponder unit and amplified by a traveling wave tube. This episode digs into the radio frequency (RF) power amplifier, explains its complicated system of relays providing redundancy, and describes how a traveling wave tube works and why they remain in use on contemporary spacecraft.

Posted at 11:44 Permalink

Thursday, October 7, 2021

CONTINUITY: NASA Transfers Crew Assigned to Boeing Starliner to SpaceX Crew Dragon

With the unmanned orbital test flight of Starliner “Hangar Queen” slipping into 2022, NASA decided the astronauts scheduled to make their first space flight on Starliner shouldn't have to wait any longer.

Posted at 15:02 Permalink

CONTINUITY: Ten Unsettling Possibilities Regarding Alien Life

It was interesting to hear the scenario from my science fiction short story “We'll Return, After This Message” figure in one of the segments.

Posted at 14:34 Permalink

THE HAPPENING WORLD: „Вызов” (The Challenge)—Teaser Trailer

Filming (or, more precisely, videography) of the 30 to 40 minutes of the feature film „Вызов” (literal translation: “Doctor's House Call”) is presently underway on the International Space Station.

Posted at 13:13 Permalink

CONTEXT: The “I Can't Believe It Can Sort” Algorithm

The abstract: “We present an extremely simple sorting algorithm. It may look like it is obviously wrong, but we prove that it is in fact correct. We compare it with other simple sorting algorithms, and analyse some of its curious properties.” Here is the full text, “Is this the simplest (and most surprising) sorting algorithm ever?” [PDF].

Posted at 12:54 Permalink

THE HAPPENING WORLD: Why Did Facebook Fail?

While the Facebook bungle has been widely described in the media as a “DNS problem”, it seemed to me from the outset that it was more likely to be due to BGP, the Border Gateway Protocol, one of the least known and potentially vulnerable part of the Internet's infrastructure. BGP, first defined in 1989 and in use on the Internet since 1994, dates from the era when the Internet was composed of a relatively small number of technically proficient and trustworthy institutions, and assumes those running it share those attributes. BGP is how the Internet routes packets among the multitude of independent networks that participate in its common network. The routers that run BGP accept routing information advertised by their peers by default. This means that a malicious router can pollute the routing tables of other routers, a form of attack known as BGP hijacking, of which a number of notable incidents have occurred, including that time in 2008 when Pakistan tried to block YouTube and ended up taking down YouTube world wide. But BGP's insecurity makes it just as prone to calamity from an unintentional fat-finger as deliberate malice, and that appears to be what happened to Facebook. It was perceived as a “DNS problem” only because Facebook's DNS servers had disappeared from the Internet, but so had everything else in Facebook's IP address ranges—that's the signature of a BGP face-plant.

BGP is neither simple nor straightforward, which is one reason it is little known, poorly understood, and easy to mess up. Here is an hour and a half deep dive into BGP, which may leave you even more confused that you are now.

Posted at 12:13 Permalink

CONTEXT: Cryptocurrency vs. Kleptocurrency

Here's the chart, in case you'd like to edit it or compare to other time series.

Posted at 01:15 Permalink

Wednesday, October 6, 2021

CONTEXT: Reading List: Escape the City, Vol. 1

Corcoran, Travis J. I. Escape the City, Vol. 1. New Hampshire: Morlock Publishing, 2021. ISBN 979-874270303-7.
In early 2014, the author and his wife left the suburbs of Boston and moved to a 56 acre homestead in rural New Hampshire. Before arriving, he had done extensive reading and research, but beyond the chores of a suburban homeowner, had little or no hands-on experience with the myriad skills required to make a go of it in the country: raising and preserving garden vegetables; maintaining pastures; raising chickens, sheep, and hogs, including butchering and processing their meat; erecting utility buildings; planting and maintaining a fruit orchard; tapping maple trees and producing syrup from their sap; managing a wood lot, felling and processing trees, storing and aging firewood and heating with it; and maintaining a tractor, implements, chainsaws, and the many tools which are indispensable to farm life. The wisdom about how tradesmen and contractors work in the country in the section “Life in The Country: Cultural Fit: Scheduling” would have been worth more than the modest price of the book had I learned it before spending a decade and a half figuring it out for myself after my own escape from the city in 1992.

This massive work (653 large pages in print) and its companion Volume 2 are an encyclopedic compendium of lessons learned and an absolutely essential resource for anybody interested in self-sufficient living, whether as a “suburbanite in the country”, “gardener with chickens”, “market gardener”, “homesteader”, or “commercial farmer”, all five of which are discussed in the book.

The Kindle edition is free for Kindle Unlimited subscribers. The numerous illustrations are in black and white in print editions, but colour in the Kindle version.

Posted at 21:14 Permalink

CONTINUITY: TOI-178—Music of the Spheres

The exoplanet system TOI-178 in the constellation of Sculptor has six planets orbiting close to a K type orange dwarf star. Five of the planets appear to be locked into a chain of Laplace resonances, resulting in regular alignments as they orbit. This artist's animation shows the planets orbiting the stars, with musical notes playing for each planet as it completes a half orbit. When planets align at these points, a resonance is heard.

Posted at 13:58 Permalink

THE HAPPENING WORLD: Finally—Optical Illusion Jeans for “Perky Buttocks”

Here is U.S. Patent 11,129,422, “Body-enhancing garment and garment construction” (full text).

Posted at 13:29 Permalink

CONTINUITY: How Photolithography Works—Part 2: Photolithography Basics

Posted at 12:47 Permalink

TRACKING WITH CLOSEUPS: Blue Origin: 2018 Consultants' Report Warns of Lack of Focus

In 2018, Blue Origin hired a consultant firm to assess Blue's competitive position with respect to SpaceX. Ars Technica has obtained a copy of the their report to CEO Bob Smith, which Eric Berger summarises in an article, “Revealed: The secret notes of Blue Origin leaders trying to catch SpaceX” published on 2021-10-04. The memo included some pungent quotes from senior Blue Origin managers.

They [SpaceX] have a customer focus. We should too. In many cases we view the customer as a nuisance. … We need to change this culture.

SpaceX shifted the market to their payload capabilities and risk profile with their low-cost launches. Blue has pushed to exceed the market’s current capabilities for size and mass. … How confident are we that the market will design to our capabilities?

Cost as a design constraint and important variable is embraced by their [SpaceX's] culture, instead of being viewed as an evil metric that leads to a sub-optimal outcome.

Blue is riddled with poor estimating. The estimates barely cover the spot cost buy of that material based on market price, let alone the entire part material purchase. How did SpaceX keep to their target cost? They probably did a good job estimating. How they accomplished such good estimating is beyond me right now, but they did it somehow for their early years.

I would like to see us change how we reward teams and individuals for company or project level success. Dinners, shirts and parties can only get us so far. I think real and meaningful financial incentives for Blue employees can help.

My strategy at Autodesk was just:

  1. Make the best product.
  2. No bullshit.
  3. Reward the people who do the work.

Perhaps Blue Origin could adopt a similar approach.

Posted at 11:53 Permalink

Tuesday, October 5, 2021

CONTINUITY: F-111 Terrain Following Radar

This training film shows the F-111's terrain following radar in action. Did you know that it had a “ride control” which set how closely it would stick to the actual terrain contour, expressed in how many Gs it would pull in climb and dive maneuvers to maintain the set altitude?

Posted at 14:03 Permalink

TRACKING WITH CLOSEUPS: Bad Rigging: Why Things Fall from Cranes

I'll bet many people using hoists fail to account for the “cosine loss” when multiple straps are used at an angle to the vertical. The shallower the angle of the strap, the more of its strength is wasted on horizontal force which simply cancels the horizontal force of the other strap(s).

Posted at 13:17 Permalink

CONTEXT: Transparent Monsters: Underestimating the Human Potential

This is a good introduction to what I call the “human endowment”—a future in which humans and their descendants will bring life, consciousness, and purpose to a solar system and beyond which awaits them. David Deutsch's The Beginning of Infinity is an excellent introduction to humans as “universal explainers” and the consequences of that for the cosmos.

Posted at 12:26 Permalink

THE HAPPENING WORLD: William Shatner to Fly to Space on Blue Origin New Shepard

Shatner is scheduled to fly on mission NS-18 on 2021-10-12, along with Blue Origin vice president Audrey Powers and two paying passengers. At age 90, he will become the oldest person to fly in space, eclipsing the record set by Wally Funk, 82, on the first crewed New Shepard flight.

There were earlier rumours that Shatner was to fly on Virgin Galactic's ship, but it appears he decided that after so many years exploring strange new worlds, seeking out new life and new civilisations, he didn't want to go into the record books as an “asterisknaut”.

Posted at 11:57 Permalink

THE HAPPENING WORLD: Soyuz MS-19 Launch to the International Space Station

As described in yesterday's post, Soyuz MS-19 is on its way to the International Space Station. I have cued the video to start one minute before launch: scroll backward if you wish to see the more than three hours of preliminary material.

Here is Scott Manley with more details about the mission and another forthcoming cross-over episode of fictional and real space flight, plus the last Khan of Kazakhstan.

Posted at 11:32 Permalink

Monday, October 4, 2021

CONTINUITY: How Photolithography Works—Part 1: Introduction

The semiconductor revolution is largely based upon the ability to manufacture identical complex objects in enormous quantities just by taking pictures of them, a process known as photolithography. But how does it work? This exploration begins with the basics: transistors, Moore's Law, and the exponential growth in the number of transistors manufactured, which is now approaching the number of stars in the visible universe.

Posted at 15:25 Permalink

THE HAPPENING WORLD: Soyuz MS-19 to Launch Film Crew to International Space Station

Launch is scheduled for 08:55 UTC on 2021-10-05. On board will be Anton Shkaplero, commander and flight engineer, film director Klim Shipenko, and actress Yulia Peresild. The 12 day mission is to film footage for the dramatic series “The Challenge”, the first four episodes of which may be viewed at 1tv.ru.

Posted at 14:10 Permalink

TRACKING WITH CLOSEUPS: Flying Insects at 6000 Frames per Second

Posted at 13:47 Permalink

CONTEXT: Chaos in the Cockpit—Botched A350 Go-Around at Paris Orly

The video observes that long haul airline crews make so few landings that five years may elapse between their having to perform a go-around in the real world (as opposed to the simulator).

Posted at 11:28 Permalink

Sunday, October 3, 2021

CONTINUITY: The Rolls-Royce Merlin Engine

Best known for powering the World War II Spitfire, Hurricane, and Mustang fighters, the many models of Rolls-Royce Merlin were used in more than forty aircraft types and was even adapted into a variant called the Meteor, used in nine models of British tanks, and remaining in production until 1964.

Posted at 15:23 Permalink

CONTINUITY: India's Evolving Space Launch Vehicles

Posted at 14:16 Permalink

CONTEXT: Blue Bananas, Autumn Leaves, Chlorophyll, and Programmed Cell Death

Posted at 12:07 Permalink

THE HAPPENING WORLD: Weekly Space Report: Starship Cryogenic Testing Begins, Tiles Fall, Lucy Asteroid Mission Launch

Posted at 11:38 Permalink

Saturday, October 2, 2021

CONTINUITY: MOSFET—How the Metal Oxide Semiconductor Field Effect Transistor Changed the World

I remember when I first played around with a 3N128 [PDF] metal insulated gate field effect transistor in the mid-1960s. It was the first essentially ideal electronic component I ever encountered. The gate current was essentially zero—just what you needed to charge or discharge its tiny capacitance, and response was almost perfectly linear within its specified range. There was no gate protection: you had to be very careful not to zap the gate with static electricity when the device was not in circuit. Who could have imagined that, half a century later, its silicon descendants would be manufactured in quantities of thousands of trillions per day—the product the most manufactured in human history? The number of MOSFETs made per year is around two million times the number of stars in the Milky Way galaxy, and the number made since their invention now exceeds the highest estimates for the number of grains of sand in all of the beaches of the Earth.

Posted at 12:36 Permalink

CONTINUITY: Post-Apocalyptic Fiction

Posted at 12:17 Permalink

CONTEXT: Akademik Lomonosov—Russia's Floating Nuclear Power Plant

Here is more about the Akademik Lomonosov, which went into service on May 22nd, 2020, delivering 70 megawatts (electric) from two KLT-40S naval propulsion reactors to the arctic community of Pevek in the Russian far east. Sixty megawatts of waste heat from the power plant is used in a community heating system, and a desalination plant provides fresh water to the town.

Posted at 11:46 Permalink

THE HAPPENING WORLD: James Webb Space Telescope—Hardware and Science

Posted at 11:19 Permalink

TRACKING WITH CLOSEUPS: Apple iPhone 13 Anti-Repair “Features”

Pretty much every component is “paired”, and only Apple has the tools to re-pair (heh) replacements. Swap a failed part for a spare, and features just magically go away. Just another reason I'm glad I bid adieu to the Pod people when the battery in “old sweller” tried to escape the case.

Posted at 10:19 Permalink

Friday, October 1, 2021

CONTINUITY: Navigating Virtual Worlds

The second part of Raph Koster's series, “How Virtual Worlds Work” (read Part 1) discusses the nature of maps of real versus imaginary spaces, moving around the map vs. a map tracking your movement, and the need for standards that treat maps in a compatible way that represents connectiivity, nor just artwork, as is so often the case.

It's easy to imagine a metaverse where “it's all connected, and you can go anywhere preserving your identity”, as envisioned in Ready Player One. But how will this really work and feel in practice?

By definition though, any multiverse (and remember, a metaverse is just a more advanced version of a multiverse) is going to involve many very different places. You don’t want those all to exist on one map. You’d end up with Fairyland butting up against World War II.

Aesthetics isn’t the main reason this is bad. The real issue is that players won’t be happy if they were expecting a nice peaceful tea party with talking flowers, but they took one step too far, and were run over by a Sherman tank.

For a glimpse of artificial reality as it might actually look if implemented by today's creators of “social media” with the underlying quality and respect for the customer we've come to expect from outfits such as Microsoft, Facebook, Twitter, and Google, see the short video cited in the paper, “Hyper-Reality” by Keiichi Matsuda.

Posted at 14:27 Permalink

THE HAPPENING WORLD: Intel Announces Neuromorphic Chip with One Million Neurons, 4 Nanometre Process

Here is an interview with Mike Davies, director of Intel's Neuromorphic Computing Lab, on the architecture of the Loihi 2 chip, applications of neuromorphic (biomimetic) technology, and how such systems are interfaced to conventional computers. Here is a technical brief [PDF] on Loihi 2 and the Lava software framework that supports it, which allows simulation of neuromorphic systems on conventional hardware. Lava is available for free from GitHub.

Posted at 12:29 Permalink

TRACKING WITH CLOSEUPS: Soyuz MS-18 Repositioning at International Space Station—Onboard TIme Lapse

Posted at 11:55 Permalink

CONTEXT: Solar Observation Spacecraft Discover Sun-Grazing Comets

Prior to the advent of space-based solar observatories, a multitude of small comets plunged in from the outer solar system and closely approached the Sun without being observed—astronomers may have suspected they existed, but there was no way to see them in the glare of the Sun. After the launch of the SOHO spacecraft in 1995 and successors since then, more than four thousand sungrazing comets have been observed, most of which disintegrate when they pass close to the Sun and do not emerge from their perihelion passage. Many of these are of the Kreutz sungrazer family, which are believed to have originated from a single large comet which broke up when passing near the Sun several centuries ago.

Posted at 10:38 Permalink