If you are from the US, you might be surprised at how prevalent roundabouts are in most of the world. Outside of Carmel, Indiana which has 125 roundabouts, these are pretty unusual in the United States though have been gaining in popularity over the past decade. It turns out, that while a modern roundabout is safer and more efficient than other intersection types, roundabouts got a bad rap early on and so the typical US driver still has a lot of anxiety when approaching one.
Prior to 1966, traffic circles were a spotty thing. In some cases, they were just big circular junctions. In others, the right-of-way rules were difficult to figure out or there were traffic lights and stop signs that did not lead to a better or safer driving experience.
Enter Frank Blackmore. In the UK, he introduced the “Priority Rule” which — simply — mandates that traffic entering a circle must give way to traffic already in the circle. Blackmore worked out that this method increases traffic flow by 10%. Although this kind of roundabout became law in the UK in 1966, the US was slow to adopt, primarily due to negative public opinion. In 2016, there were about 4,800 modern roundabouts in the U.S while France and the UK have roughly 55,000 combined.
So what are the virtues of the modern rounabout, and where did it come from? Let’s take a look.
Because of the architecture used for the Apollo missions, extended stays on the surface of the Moon weren’t possible. The spartan Lunar Module simply wasn’t large enough to support excursions of more than a few days in length, and even that would be pushing the edge of the envelope. But then the Apollo program was never intended to be anything more than a proof of concept, to demonstrate that humans could make a controlled landing on the Moon and return to Earth safely. It was always assumed that more detailed explorations would happen on later missions with more advanced equipment and spacecraft.
Now NASA hopes that’s finally going to happen in the 2020s as part of its Artemis program. These missions won’t just be sightseeing trips, the agency says they’re returning with the goal of building a sustainable infrastructure on and around our nearest celestial neighbor. With a space station in lunar orbit and a permanent outpost on the surface, personnel could be regularly shuttled between the Earth and Moon similar to how crew rotations are currently handled on the International Space Station.
Artemis lander concept
Naturally, there are quite a few technical challenges that need to be addressed before that can happen. A major one is finding ways to safely and accurately deliver multiple payloads to the lunar surface. Building a Moon outpost will be a lot harder if all of its principle modules land several kilometers away from each other, so NASA is partnering with commercial companies to develop crew and cargo vehicles that are capable of high precision landings.
But bringing them down accurately is only half the problem. The Apollo Lunar Module is by far the largest and heaviest object that humanity has ever landed on another celestial body, but it’s absolutely dwarfed by some of the vehicles and components that NASA is considering for the Artemis program. There’s a very real concern that the powerful rocket engines required to gracefully lower these massive craft to the lunar surface might kick up a dangerous cloud of high-velocity dust and debris. In extreme cases, the lander could even find itself touching down at the bottom of a freshly dug crater.
Of course, the logical solution is to build hardened landing pads around the Artemis Base Camp that can support these heavyweight vehicles. But that leads to something of a “Chicken and Egg” problem: how do you build a suitable landing pad if you can’t transport large amounts of material to the surface in the first place? There are a few different approaches being considered to solve this problem, but certainly one of the most interesting among them is the idea proposed by Masten Space Systems. Their experimental technique would allow a rocket engine to literally build its own landing pad by spraying molten aluminum as it approaches the lunar surface.
Air-to-air combat or “dogfighting” was once a very personal affair. Pilots of the First and Second World War had to get so close to land a hit with their guns that it wasn’t uncommon for altercations to end in a mid-air collision. But by the 1960s, guided missile technology had advanced to the point that a fighter could lock onto an enemy aircraft and fire before the target even came into visual range. The skill and experience of a pilot was no longer enough to guarantee the outcome of an engagement, and a new arms race was born.
An F-15 launching flare countermeasures.
Naturally, the move to guided weapons triggered the development of defensive countermeasures that could confuse them. If the missile is guided by radar, the target aircraft can eject a cloud of metallic strips known as chaff to overwhelm its targeting system. Heat-seeking missiles can be thrown off with a flare that burns hotter than the aircraft’s engine exhaust. Both techniques are simple, reliable, and have remained effective after more than a half-century of guided missile development.
But they aren’t perfect. The biggest problem is that both chaff and flares are a finite resource: once the aircraft has expended its stock, it’s left defenseless. They also only work for a limited amount of time, which makes timing their deployment absolutely critical. Automated dispensers can help ensure that the countermeasures are used as efficiently as possible, but sustained enemy fire could still deplete the aircraft’s defensive systems if given enough time.
In an effort to develop the ultimate in defensive countermeasures, the United States Navy has been working on a system that can project decoy aircraft in mid-air. Referred to as “Ghosts” in the recently published patent, several of these phantom aircraft could be generated for as long as the system has electrical power. History tells us that the proliferation of this technology will inevitably lead to the development of an even more sensitive guided missile, but in the meantime, it could give American aircraft a considerable advantage in any potential air-to-air engagements.
Modern physics experiments are often complex, ambitious, and costly. The times where scientific progress could be made by conducting a small tabletop experiment in your lab are mostly over. Especially, in fields like astrophysics or particle physics, you need huge telescopes, expensive satellite missions, or giant colliders run by international collaborations with hundreds or thousands of participants. To drive this point home: the largest machine ever built by humankind is the Large Hadron Collider (LHC). You won’t be surprised to hear that even just managing the data it produces is a super-sized task.
Since its start in 2008, the LHC at CERN has received several upgrades to stay at the cutting edge of technology. Currently, the machine is in its second long shutdown and being prepared to restart in May 2021. One of the improvements of Run 3 will be to deliver particle collisions at a higher rate, quantified by the so-called luminosity. This enables experiments to gather more statistics and to better study rare processes. At the end of 2024, the LHC will be upgraded to the High-Luminosity LHC which will deliver an increased luminosity by up to a factor of 10 beyond the LHC’s original design value.
Currently, the major experiments ALICE, ATLAS, CMS, and LHCb are preparing themselves to cope with the expected data rates in the range of Terabytes per second. It is a perfect time to look into more detail at the data acquisition, storage, and analysis of modern high-energy physics experiments. Continue reading “Crunching Giant Data From The Large Hadron Collider”→
As electric utilization, adoption of electric cars, and the use of renewable power continues to rise, engineers all over are searching for the perfect utility scale battery. We have all heard about Tesla’s 100MW lithium battery pack in South Australia. The system is a massive success and has already paid itself back. However, engineers all over were quick to point out that, until we have a breakthrough, Lithium cells are just not the right choice for a utility system in the long run. There has to be a better solution. Continue reading “A Redox Flow Battery Made From Iron Industry Waste”→
The news is full of the record low oil price due to the COVID-19-related drop in demand. The benchmark Brent crude dipped below $20 a barrel, while West Texas intermediate entered negative pricing. We’ve all become oil market watchers overnight, and for some of us that’s led down a rabbit hole of browsing to learn a bit about how oil is extracted.
Many of us will have seen offshore oil platforms or nodding pumpjacks, but how many of us outside the industry have much more than a very superficial knowledge of it? Of all the various technologies to provide enlightenment of the curious technologist there’s one curious survivor from the earliest days of the industry that is definitely worth investigation, the jerk line oil well pump. This is a means of powering a reciprocating pump in an oil well not through an individual engine or motor as in the pump jacks, but in a system of rods transmitting power over long distances from a central location by means of reciprocating motion. It’s gloriously simple, which has probably contributed to its survival in a few small-scale oil fields over a century and a half after its invention.
Stephen Wolfram, inventor of the Wolfram computational language and the Mathematica software, announced that he may have found a path to the holy grail of physics: A fundamental theory of everything. Even with the subjunctive, this is certainly a powerful statement that should be met with some skepticism.
What is considered a fundamental theory of physics? In our current understanding, there are four fundamental forces in nature: the electromagnetic force, the weak force, the strong force, and gravity. Currently, the description of these forces is divided into two parts: General Relativity (GR), describing the nature of gravity that dominates physics on astronomical scales. Quantum Field Theory (QFT) describes the other three forces and explains all of particle physics. Continue reading “Wolfram Physics Project Seeks Theory Of Everything; Is It Revelation Or Overstatement?”→
