Apollo Lunar Surface Experiments Package of the Apollo 16 mission (Credit: NASA)

ALSEP: Apollo’s Modular Lunar Experiments Laboratory

December 23, 2024 by Maya Posch 13 Comments

Down-Sun picture of the RTG with the Central Station in the background. (Credit: NASA)

Although the US’ Moon landings were mostly made famous by the fact that it featured real-life human beings bunny hopping across the lunar surface, they weren’t there just for a refreshing stroll over the lunar regolith in deep vacuum. Starting with an early experimental kit (EASEP) that was part of the Apollo 11 mission, the Apollo 12 through Apollo 17 were provided with the full ALSEP (Apollo Lunar Surface Experiments Package). It’s this latter which is the subject of a video by [Our Own Devices].

Despite the Apollo missions featuring only one actual scientist (Harrison Schmitt, geologist), these Bendix-manufactured ALSEPs were modular, portable laboratories for running experiments on the moon, with each experiment carefully prepared by scientists back on Earth. Powered by a SNAP-27 radioisotope generator (RTG), each ALSEP also featured the same Central Station command module and transceiver. Each Apollo mission starting with 12 carried a new set of experimental modules which the astronauts would set up once on the lunar surface, following the deployment procedure for that particular set of modules.

Although the connection with the ALSEPs was terminated after the funding for the Apollo project was ended by US Congress, their transceivers remained active until they ran out of power, but not before they provided years worth of scientific data on many aspects on the Moon, including its subsurface characteristics and exposure to charged particles from the Sun. These would provide most of our knowledge of our Moon until the recent string of lunar landings by robotic explorers.

Heading image: Apollo Lunar Surface Experiments Package of the Apollo 16 mission (Credit: NASA)

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Illustrative models of collinear ferromagnetism, antiferromagnetism, and altermagnetism in crystal-structure real space and nonrelativistic electronic-structure momentum space. (Credit: Libor Šmejkal et al., Phys. Rev. X, 2022)

Nanoscale Imaging And Control Of Altermagnetism In MnTe

December 21, 2024 by Maya Posch No comments

Altermagnetism is effectively a hybrid form of ferromagnetism and antiferromagnetism that might become very useful in magnetic storage as well as spintronics in general. In order to practically use it, we first need to be able to control the creation of these altermagnets, which is what researchers have now taken the first steps towards. The research paper by [O. J. Amin] et al. was published earlier this month in Nature. It builds upon the team’s earlier research, including the detection of altermagnetism in manganese telluride (MnTe). This new study uses the same material but uses a photoemission electron microscope (PEEM) with X-rays to image these nanoscale altermagnetic structures.

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Measuring A Well With Just A Hammer And A Smartphone

December 19, 2024 by Dan Maloney 38 Comments

What’s the best way to measure the depth of a well using a smartphone? If you’re fed up with social media, you might kill two birds with one stone and drop the thing down the well and listen for the splash. But if you’re looking for a less intrusive — not to mention less expensive — method, you could also use your phone to get the depth acoustically.

This is a quick hack that [Practical Engineering Solutions] came up with to measure the distance to the surface of the water in a residential well, which we were skeptical would work with any precision due to its deceptive simplicity. All you need to do is start a sound recorder app and place the phone on the well cover. A few taps on the casing of the well with a hammer send sound impulses down the well; the reflections from the water show up in the recording, which can be analyzed in Audacity or some similar sound editing program. From there it’s easy to measure how long it took for the echo to return and calculate the distance to the water. In the video below, he was able to get within 3% of the physically measured depth — pretty impressive.

Of course, a few caveats apply. It’s important to use a dead-blow hammer to avoid ringing the steel well casing, which would muddle the return signal. You also might want to physically couple the phone to the well cap so it doesn’t bounce around too much; in the video it’s suggested a few bags filled with sand as ballast could be used to keep the phone in place. You also might get unwanted reflections from down-hole equipment such as the drop pipe or wires leading to the submersible pump.

Sources of error aside, this is a clever idea for a quick measurement that has the benefit of not needing to open the well. It’s also another clever use of Audacity to use sound to see the world around us in a different way.

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Human Civilization And The Black Plastic Kitchen Utensils Panic

December 19, 2024 by Maya Posch 98 Comments

Recently there was a bit of a panic in the media regarding a very common item in kitchens all around the world: black plastic utensils used for flipping, scooping and otherwise handling our food while preparing culinary delights. The claim was that the recycled plastic which is used for many of these utensils leak a bad kind of flame-retardant chemical, decabromodiphenyl ether, or BDE-209, at a rate that would bring it dangerously close to the maximum allowed intake limit for humans. Only this claim was incorrect because the researchers who did the original study got their calculation of the intake limit wrong by a factor of ten.

This recent example is emblematic of how simple mistakes can combine with a reluctance to validate conclusions can lead successive consumers down a game of telephone where the original text may already have been wrong, where each node does not validate the provided text, and suddenly everyone knows that using certain kitchen utensils, microwaving dishes or adding that one thing to your food is pretty much guaranteed to kill you.

How does one go about defending oneself from becoming an unwitting factor in creating and propagating misinformation?

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Survival mechanisms in Deinococcus radiodurans bacterium. (Credit: Feng Liu et al., 2023)

Bacterium Demonstrates Extreme Radiation Resistance Courtesy Of An Antioxidant

December 18, 2024 by Maya Posch 12 Comments

Extremophile lifeforms on Earth are capable of rather astounding feats, with the secret behind the extreme radiation resistance of one of them now finally teased out by researchers. As one of the most impressive extremophiles, Deinococcus radiodurans is able to endure ionizing radiation levels thousands of times higher than what would decisively kill a multicellular organism like us humans. The trick is the antioxidant which this bacterium synthesizes from multiple metabolites that combine with manganese. An artificial version of this antioxidant has now been created that replicates the protective effect.

The ternary complex dubbed MDP consists of manganese ions, phosphate and a small peptide, which so far has seen application in creating vaccines for chlamydia. As noted in a 2023 study in Radiation Medicine and Protection by [Feng Liu] et al. however, the D. radiodurans bacterium has more survival mechanisms than just this antioxidant. Although much of the ionizing radiation is neutralized this way, it can not be fully prevented. This is where the highly effective DNA repair mechanism comes into play, along with a range of other adaptations.

The upshot of this is the synthesis of a very effective and useful antioxidant, but as alluded to in the press releases, just injecting humans with MDP will not instantly give them the same super powers as our D. radiodurans buddy.

Featured image: Survival mechanisms in Deinococcus radiodurans bacterium. (Credit: Feng Liu et al., 2023)

Upper Room UV-C Keeps Air Cleaner

December 18, 2024 by Lewin Day 59 Comments

2020 saw the world rocked by widespread turmoil, as a virulent new pathogen started claiming lives around the globe. The COVID-19 pandemic saw a rush on masks, air filtration systems, and hand sanitizer, as terrified populations sought to stave off the deadly virus by any means possible.

Despite the fresh attention given to indoor air quality and airborne disease transmission, there remains one technology that was largely overlooked. It’s the concept of upper-room UV sterilization—a remarkably simple way of tackling biological nastiness in the air.

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Single Crystal Electrode Lithium Ion Batteries Last A Long Time

December 16, 2024 by Al Williams 77 Comments

Researchers have been testing a new type of lithium ion battery that uses single-crystal electrodes. Over several years, they’ve found that the technology could keep 80% of its capacity after 20,000 charge and discharge cycles. For reference, a conventional cell reaches 80% after about 2,400 cycles.

The researchers say that the number of cycles would be equivalent to driving about 8 million kilometers in an electric vehicle. This is within striking distance of having the battery last longer than the other parts of the vehicle. The researchers employed synchrotron x-ray diffraction to study the wear on the electrodes. One interesting result is that after use, the single-crystal electrode showed very little degradation. According to reports, the batteries are already in production and they expect to see them used more often in the near future.

The technology shows promise, too, for other demanding battery applications like grid storage. Of course, better batteries are always welcome, although it is hard to tell which new technologies will catch on and which will be forgotten.

There are many researchers working on making better batteries. Even AI is getting into the act.