- Popular-level introduction to the five methods used to identify exoplanets.
- Another good profile of the SEP.
- ArXiv gets some money to improve stuff.
- Flying fish are hard to believe. It’s something of a tragedy that fish capable of long-distance flight never evolved (that we know of?). They are so bird like it’s startling, and this ability has evolved independently multiple times.
- In addition to Russia and China, the US also at one time had ICBMs deployed by rail.
For nuclear power plants governed by the United States Nuclear Regulatory Commission, SAFSTOR (SAFe STORage) is one of the options for nuclear decommissioning of a shut down plant. During SAFSTOR the de-fuelled plant is monitored for up to sixty years before complete decontamination and dismantling of the site, to a condition where nuclear licensing is no longer required. During the storage interval, some of the radioactive contaminants of the reactor and power plant will decay, which will reduce the quantity of radioactive material to be removed during the final decontamination phase.
The other options set by the NRC are nuclear decommissioning which is immediate dismantling of the plant and remediation of the site, and nuclear entombment which is the enclosure of contaminated parts of the plant in a permanent layer of concrete.Mixtures of options may be used, for example, immediate removal of steam turbine components and condensors, and SAFSTOR for the more heavily radioactive containment vessel. Since NRC requires decommissioning to be completed within 60 years, ENTOMB is not usually chosen since not all activity will have decayed to an unregulated background level in that time.
- The fraction of the federal budget devoted to NASA peaked in 1966, three years before the Moon landing.
- Elephants are secretly wearing high heels.
- Cost per unit hard-drive space is flattening (for consumer models).
Crux was known to the Ancient Greeks due to the fact that it can be seen from southern Egypt; Ptolemy regarded it as part of the constellation Centaurus. It was entirely visible as far north as Britain in the fourth millennium BC. However, the precession of the equinoxes gradually lowered its stars below the European horizon, and they were eventually forgotten by the inhabitants of northern latitudes. By AD 400, most of the constellation never rose above the horizon for Athenians.
- Zotero 5.0 has significant changes and is out now.
- “Mainland China has 36 nuclear power reactors in operation, 21 under construction, and more about to start construction.” See also Wikipedia and this long piece on Chinese investment in Namibia. In comparison, the US gets essentially all nuclear power from reactors built at least 30 years ago, and has just 4 new reactors under construction.
- Sentience Institute: “In discussions of effective animal advocacy (EAA) — the field of study for how we can most effectively help animals, also known as effective altruism for animals — there are several important, challenging, and sometimes controversial foundational questions that come up over and over. This post attempts to summarize and catalog the key evidence cited by EAA supporters on each side of these debates for easy reference.”
- Third black hole merger detected by LIGO. No neutron stars yet. Binary BH distribution might be more massive and have more misaligned spins than popular models. Nothing revelatory.
- Vulcan aerospace unveils airplane with world’s largest wingspan (by far) as part of air-launch orbital rocket service.
- Methane hydrates will be the new shale gas. There is perhaps an order of magnitude more methane worldwide in hydrates than in shale deposits, but it’s harder to extract. “…it’s thought that only by 2025 at the earliest we might be able to look at realistic commercial options.”
- Sperm whales have no (external) teeth on their upper jaw, which instead features holes into which the teeth on their narrow lower jaw fit.
- Surprising and heartening to me: GiveWell finds that distributing antiretroviral therapy drugs to HIV positive patients (presumably in developing countries) is potentially cost-effective compared to their top recommendations.
- Relatedly: the general flow of genetic information is DNA-RNA-protein. At a crude level, viruses are classified as either RNA viruses or DNA viruses depending on what sort of genetic material they carry. Generally, as parasites dependent on the host cell machinery, this determines where in the protein construction process they inject their payload. However, retroviruses (like HIV) are RNA viruses that bring along their own reverse transcriptase enzyme that, once inside the cell, converts their payload back into DNA and then grafts it into the host’s genome (which is then copied as part of the host cell’s lifecycle). Once this happens, it is very difficult to tell which cells have been infected and very difficult to root out the infection.
I remember reading about the common pitfalls of vertically integrated companies when I was in school. While there are usually some compelling cost savings to be had from vertical integration (either through insourcing services or acquiring suppliers/customers), the increased margins typically evaporate over time as the “supplier” gets complacent with a captive, internal “customer.”
- Why does a processor need billions of transistors if it’s only ever executing a few dozen instructions per clock cycle?
- Nuclear submarines as refuges from global catastrophes.
…corporate transactions such as mergers and acquisitions or financings are characterized by several salient facts that lack a complete theoretical account. First, they are almost universally negotiated through agents. Transactional lawyers do not simply translate the parties’ bargain into legally enforceable language; rather, they are actively involved in proposing and bargaining over the transaction terms. Second, they are negotiated in stages, often with the price terms set first by the parties, followed by negotiations primarily among lawyers over the remaining non-price terms. Third, while the transaction terms tend to be tailored to the individual parties, in negotiations the parties frequently resort to claims that specific terms are (or are not) “market.” Fourth, the legal advisory market for such transactions is highly concentrated, with a half-dozen firms holding a majority of the market share.
[Our] claim is that, for complex transactions experiencing either sustained innovation in terms or rapidly changing market conditions, (1) the parties will maximize their expected surplus by investing in market information about transaction terms, even under relatively competitive conditions, and (2) such market information can effectively be purchased by hiring law firms that hold a significant market share for a particular type of transaction.
…The considerable complexity of corporate transaction terms creates an information problem: One or both parties may simply be unaware of the complete set of surplus-increasing terms for the transaction, and of their respective outside options should negotiations break down. This problem is distinct from the classic problem of valuation uncertainty.
- The timeframe for the origin of language has incredible uncertainty, with experts proposing numbers between 50k and 2M years ago (almost 2 orders of magnitude spread).
- Popehat on how US Federal Criminal Sentencing works.
- Amazon medium-frequency pricing.
- Ship tunnel.
- First SpaceX re-launch goes off without a hitch, including a repeat landing at sea for the 1st stage. As a bonus, they pseduo-recovered the fairing for the first time, which (surprisingly to me) costs north of $5M each. (The fairing splashed down in the ocean, but in the future they will apparently land on an inflatable cushion target.) Lots more details revealed at press conference summarized in this /r/SpaceX thread. Even second-stage recovery is back on the table.
- Mostly unrelated tidbit: SpaceX rockets are only capable of horizontal, not vertical, payload integration.
Scott Alexander points to this blog post discussing how the venerable NYTimes massages plots to tell the story they want to tell. The NY Times is far from alone in doing this, of course. The depressing part is that if even they are doing it, who isn’t? Now’s as good a time as ever to reiterate that the Times explicitly condones narration and eschews neutrality. In the words of their ombudsman:
I often hear from readers that they would prefer a straight, neutral treatment — just the facts. But The Times has moved away from that, reflecting editors’ reasonable belief that the basics can be found in many news outlets, every minute of the day. They want to provide “value-added” coverage.
Also from Scott: Heritability and stability of intelligence vs. personality:
Results: Both cognition and personality are moderately heritable and exhibit large increases in stability with age; however, marked differences are evident.
If you are a high school student, or know one, who would be interested in the SPARC summer camp, the deadline is March 1.
SPARC helps talented high school students apply their quantitative thinking skills to their lives and the world.
SPARC will be hosted in the San Francisco Bay Area from August 6 – 17, with students arriving the evening of the 6th and leaving the morning of the 17th. Room and board are provided free of charge.
The curriculum covers topics from causal modeling and probability to game theory and cognitive science. But the focus of SPARC is on applying the same quantitative and rigorous spirit outside of the classroom. How can we understand our own reasoning and behavior? How can we think more clearly and better achieve our goals?
- Indian Space Research Organisation’s Polar Satellite Launch Vehicle successfully launched 104 satellites into orbit on the same mission. Onboard video of the deployment:
Pictures of some of the cubesats, including Planet‘s 88 imagining satellites for continuous Earth monitoring.
- “What is a ‘Shavers Only’ Electrical Outlet?”
- A possible rare shake-up of the GiveWell list: temporary subsidies for migrant workers in India.
How to think about cell walls:
I most cells, the cell wall is flexible, meaning that it will bend rather than holding a fixed shape, but has considerable tensile strength. The apparent rigidity of primary plant tissues is enabled by cell walls, but is not due to the walls’ stiffness. Hydraulic turgor pressure creates this rigidity, along with the wall structure. The flexibility of the cell walls is seen when plants wilt, so that the stems and leaves begin to droop, or in seaweeds that bend in water currents.
- “A Four Planet System in Orbit, Directly Imaged“.
- The main arched cover of the new 100-year sarcophagus for the Chernobyl site was slid into place in November, the largest object ever moved.
- “Time-resolved 2-million-year-old supernova activity discovered in Earth’s microfossil record”
- How do you make reasonable decisions under large empirical and normative uncertainty when literally billions of dollars are at stake? Holden Koronophsky grapples with this extreme version of a key EA dilemma. Relatedly: this Wired profile of John Arnold, billionaire trader who pioneered some evidence-based philanthropic strategies celebrated by EAs.
- New strong evidence for the hypothesis that schizophrenia is ameliorated by nicotine. This suggests that there were serious negative effects of unfocused efforts to stop smoking with, e.g., blanket bans at psych hospitals, as emphasized by Scott Alexander. Also by way of Scott: Agora is an experimental web forum threading system where comments can not only have multiple branching reply comments (like reddit) but also be in reply to multiple parent comments.
- Alex Tabarrok on the importance of the FDA commissioner.
- “Why it Takes so Long to Connect to a WiFi Access Point?” (Excellent HN discussion.)
- More on the recent success of solid C02 sequestration in Iceland.
- OK, this is extremely sappy, but I’m a sucker for it. “Wanderers” is a short film by Erik Wernquist featuring illustrations of future exploration within the solar system with narration by Carl Sagan:
- Eliezer Yudkowsky and Bryan Caplan bet on the end of the world.
- PRL is now charging authors $800 and that doesn’t include open access (which is $2900)?
Late, alas. Also: there have been a couple of complaints about the spam filter for comments on this blog, and I’m trying to track down the issue. The filter is supposed to tell you what’s wrong and help you successfully post the comment. If you’ve been unable to get past the filter, or if it’s just too much of a hassle even when you can get past it, please let me know so I can try to fix this.
- Europe’s Galileo satellite navigation system recently went online, although without yet a complete constellation. In just a few years, there will be a full four independent navigations from great powers: the EU, the US (GPS), Russia (GLONASS), and China (BeiDou). Devices are already being built to use all four systems at once. Everyone wins through the increased redundancy and satellite count.
- Design of the Solo cup.
- I highly recommend this semi-technical talk on ARC fusion reactor design by Dennis Whyte.
(Video DownloadHelper allows downloading video off YouTube.)
Proposed in 2014 by Whyte and collaborators, ARC is a newer but only under-development alternative to traditional Tokamak-style reactor, where rare earth barium copper oxide (ReBCo) superconductors play a crucial role. Whyte argues that the key hold-up on fusion reactors is their absolute size, which necessitate large-scale, lumbering international collaboration. ReBCo superconductors are the key technical advance allowing smaller magnetic confinement. The parameters of these designs scale extremely well with increased magnetic field. Significant downsides include increased vessel pressure and pulsed operation because of intrinsic limitations on neutrons shielding.The fusion fuel is deuterium and tritium, which is most amenable choice of reactant on the fusion slope of the nuclei binding energy curve.