For those who say there’s never enough time in a day, your wish for more time is getting granted, if ever so slightly. Scientists have now found a new source of our days getting longer — climate change.
You may have already been aware that the length of the day on Earth has been getting longer over time due to the drag exerted on our planet by our friendly neighborhood Moon. Many other factors come into play though, including the Earth’s own mass distribution. As the Earth warms and polar caps melt, the water redistributes to the Earth’s equator causing it to slow more rapidly.
In the worst-case scenario, RCP8.5, it would result in climate-related effects to planetary rotational velocity even larger than those caused by lunar tides. Under that scenario, the earth would probably be a less pleasant place to live in many other ways, but at least you’d have a little more time in your day.
Hurricanes can cause widespread destruction, so early forecasting of their strength is important to protect people and their homes. The US National Oceanic and Atmospheric Administration (NOAA) is using saildrones to get better data from inside these monster storms.
Rising ocean temperatures due to climate change are causing hurricanes to intensify more rapidly than in the past, although modeling these changes is still a difficult task. People on shore need to know if they’re in store for a tropical storm or a high strength hurricane to know what precautions to take. Evacuating an area is expensive and disruptive, so it’s understandable that people want to know if it’s necessary.
Starting with five units in 2021, the fleet has gradually increased in size to twelve last summer. These 23ft (7m), 33ft (10m), or 65ft (20m) long vessels are propelled by wing sails and power their radio and telemetry systems with a combination of solar and battery power. No fossil fueled vessel can match the up to 370 days at sea without refueling that these drones can achieve, and the ability to withstand hurricane winds and sea conditions allow scientists an up-close-and-personal look at a hurricane without risking human lives.
Many scifi robots have taken the form of their creators. In the increasingly blurry space between the biological and the mechanical, researchers have found a way to affix human skin to robot faces. [via NewScientist]
Previous attempts at affixing skin equivalent, “a living skin model composed of cells and extracellular matrix,” to robots worked, even on moving parts like fingers, but typically relied on protrusions that impinged on range of motion and aesthetic concerns, which are pretty high on the list for robots designed to predominantly interact with humans. Inspired by skin ligaments, the researchers have developed “perforation-type anchors” that use v-shaped holes in the underlying 3D printed surface to keep the skin equivalent taut and pliable like the real thing.
The researchers then designed a face that took advantage of the attachment method to allow their robot to have a convincing smile. Combined with other research, robots might soon have skin with touch, sweat, and self-repair capabilities like Data’s partial transformation in Star Trek: First Contact.
Logarithms are everywhere in mathematics and derived fields, but we rarely think about how trigonometric functions, exponentials, square roots and others are calculated after we punch the numbers into a calculator of some description and hit ‘calculate’. How do we even know that the answer which it returns is remotely correct? This was the basic question that [Zachary Chartrand] set out to answer for [3Blue1Brown]’s Summer of Math Exposition 3 (SoME-3). Inspired by learning to script Python, he dug into how such calculations are implemented by the scripting language, which naturally led to the standard C library. Here he found an interesting implementation for the natural algorithm and the way geometric series convergence is sped up.
The short answer is that fundamental properties of these series are used to decrease the number of terms and thus calculations required to get a result. One example provided in the article reduces the naïve approach from 36 terms down to 12 with some optimization, while the versions used in the standard C library are even more optimized. This not only reduces the time needed, but also the memory required, both of which makes many types of calculations more feasible on less powerful systems.
Even if most of us are probably more than happy to just keep mashing that ‘calculate’ button and (rightfully) assume that the answer is correct, such a glimpse at the internals of the calculations involved definitely provides a measure of confidence and understanding, if not the utmost appreciation for those who did the hard work to make all of this possible.
While fluid dynamics sounds like a dull topic, SoapFilmScope promises to make it fun by using your cell phone to observe the interactions between sound waves and liquid membranes. You can make your own with some PVC pipe, some 3D-printed attachments, a speaker, and a few other odds and ends.
If your PVC pipe doesn’t match [DaniloR29’s] exactly, no problem. The files are in OpenSCAD so you can easily change them to suit your needs. One end of the PVC tee dips into soap solution to form a film — think like a soap bubble before you blow it out of the bubble wand. The other ends have the speaker and the cell phone camera.
Science and engineering usually create consistent results. Generally, when you figure out how to make something, you can repeat that at will to make more of something. But what if, one day, you ran the same process, and got different results? You double-checked, and triple-checked, and you kept ending up with a different end product instead?
Perhaps it wasn’t the process that changed, but the environment? Or physics itself? Enter the scary world of disappearing polymorphs.
Could carbon fiber inflict the same kind of damage on the human body as asbestos? That’s the question which [Nathan] found himself struggling with after taking a look at carbon fiber-reinforced filament under a microscope, revealing a sight that brings to mind fibrous asbestos samples. Considering the absolutely horrifying impact that asbestos exposure can have, this is a totally pertinent question to ask. Fortunately, scientific studies have already been performed on this topic.
Example SEM and TEM images of the released particles following the rupture of CFRP cables in the tensile strength test. (Credit: Jing Wang et al, Journal of Nanobiotechnology, 2017)
While [Nathan] demonstrated that the small lengths of carbon fiber (CF) contained in some FDM filaments love to get stuck in your skin and remain there even after washing one’s hands repeatedly, the aspect that makes asbestos such a hazard is that the mineral fibers are easily respirable due to their size. It is this property which allows asbestos fibers to nestle deep inside the lungs, where they pierce cell membranes and cause sustained inflammation, DNA damage and all too often lung cancer or worse.
Clearly, the 0.5 to 1 mm sized CF strands in FDM filaments aren’t easily inhaled, but as described by [Jing Wang] and colleagues in a 2017 Journal of Nanobiotechnology paper, CF can easily shatter into smaller, sharper fragments through mechanical operations (cutting, sanding, etc.) which can be respirable. It is thus damaged carbon fiber, whether from CF reinforced thermal polymers or other CF-containing materials, that poses a potential health risk. This is not unlike asbestos — which when stable in-situ poses no risk, but can create respirable clouds of fibers when disturbed. When handling CF-containing materials, especially for processing, wearing an effective respirator (at least N95/P2) that is rated for filtering out asbestos fibers would thus seem to be a wise precaution.
The treacherous aspect of asbestos and kin is that diseases like lung cancer and mesothelioma are not immediately noticeable after exposure, but can take decades to develop. In the case of mesothelioma, this can be between 15 and 30 years after exposure, so protecting yourself today with a good respirator is the only way you can be relatively certain that you will not be cursing your overconfident young self by that time.
