The Eleven-Faced Die That Emulates Two Six-sided Dice

November 28, 2025 by Donald Papp 28 Comments

Rolling two six-sided dice (2d6) gives results from 2 to 12 with a bell curve distribution. Seven being the most common result, two and twelve being the least common. But what if one could do this with a single die?

This eleven-sided die has a distribution matching the results of 2d6.

As part of research Putting Rigid Bodies to Rest, researchers show that a single eleven-sided asymmetric shape can deliver the same results. That is to say, it rolls numbers 2 to 12 in the same distribution as 2d6. It’s actually just one of the oddball dice [Hossein Baktash] and his group designed so if you find yourself intrigued, be sure to check out the 3D models and maybe print your own!

The research behind this is a novel method of figuring out what stable resting states exist for a given rigid body, without resorting to simulations. The method is differentiable, meaning it can be used not just to analyze shapes, but also to design shapes with specific properties.

For example, with a typical three-sided die each die face has an equal chance of coming up. But [Hossein] shows (at 8:05 in the video, embedded below) that it’s possible to design a three-sided die where the faces instead have a 25%-50%-25% distribution.

How well do they perform in practice? [Hossein] has done some physical testing showing results seem to match theory, at least when rolled on a hard surface. But we don’t think anyone has loaded these into an automated dice tester, yet.

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Boosting Antihydrogen Production Using Beryllium Ions

November 25, 2025 by Maya Posch 27 Comments

Antihydrogen forms an ideal study subject for deciphering the secrets of fundamental physics due to it being the most simple anti-matter atom. However, keeping it from casually annihilating itself along with some matter hasn’t gotten much easier since it was first produced in 1995. Recently ALPHA researchers at CERN’s Antimatter Factory announced that they managed to produce and trap no fewer than 15,000 antihydrogen atoms in less than seven hours using a new beryllium-enhanced trap. This is an eight-fold increase compared to previous methods.

To produce an antihydrogen atom from a positron and an antiproton, the components and resulting atoms can not simply be trapped in an electromagnetic field, but requires that they are cooled to the point where they’re effectively stationary. This also makes adding more than one of such atom to a trap into a tedious process since the first successful capture in 2017.

In the open access paper in Nature Communications by [R. Akbari] et al. the process is described, starting with the merging of anti-protons from the CERN Antiproton Decelerator with positrons sourced from the radioactive decay of sodium-22 (β⁺ decay). The typical Penning-Malmberg trap is used, but laser-cooled beryllium ions (Be⁺) are added to provide sympathetic cooling during the synthesis step.

Together with an increased availability of positrons, the eight-fold increase in antihydrogen production was thus achieved. The researchers speculate that the sympathetic cooling is more efficient at keeping a constant temperature than alternative cooling methods, which allows for the increased rate of production.

Water On Mars? Maybe Not

November 24, 2025 by Al Williams 10 Comments

We were as excited as anyone when MARSIS (the Mars Advanced Radar for Subsurface and Ionosphere Sounding) experiment announced there was possibly liquid water under the southern polar ice cap. If there is liquid water on Mars, it would make future exploration and colonization much more feasible. Unfortunately, SHARAD (the Shallow Radar) has a new trick that suggests the data may not indicate liquid water after all.

While the news is a bummer, the way scientists used SHARAD to confirm — or, in this case, deny — the water hypothesis was a worthy hack. The SHARAD antenna is on the Mars Reconnaissance Orbiter, but in a position that makes it difficult to obtain direct surface readings from Mars. To compensate, operators typically roll the spacecraft to give the omnidirectional antenna a clearer view of the ground. However, those rolls have been under 30 degrees.

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Testing The Survivability Of Moss In Space

November 24, 2025 by Maya Posch 11 Comments

The cool part about science is that you can ask questions like what happens if you stick some moss spores on the outside of the International Space Station, and then get funding for answering said question. This was roughly the scope of the experiment that [Chang-hyun Maeng] and colleagues ran back in 2022, with their findings reported in iScience.

Used as moss specimen was Physcomitrium patens, a very common model organism. After previously finding during Earth-based experiments that the spores are the most resilient, these were subsequently transported to the ISS where they found themselves placed in the exposure unit of the Kibo module. Three different exposure scenarios were attempted for the spores, with all exposed to space, but one set kept in the dark, another protected from UV and a third set exposed to the healthy goodness of the all-natural UV that space in LEO has to offer.

After the nine month exposure period, the spores were transported back to Earth, where the spores were allowed to develop into mature P. patens moss. Here it was found that only the spores which had been exposed to significant UV radiation – including UV-C unfiltered by the Earth’s atmosphere – saw a significant reduction in viability. Yet even after nine months of basking in UV-C, these still had a germination rate of 86%, which provides fascinating follow-up questions regarding their survivability mechanisms when exposed to UV-C as well as a deep vacuum, freezing temperatures and so on.

Smelly Ultrasound

November 24, 2025 by Al Williams 26 Comments

We aren’t sure why, but [Lev Chizhov] and some other researchers have found a way to make you smell things by hitting your head with ultrasound. Apparently, your sense of smell lives in your olfactory bulb, and no one, until now, has thought to try zapping it with ultrasound to see what happens.

The bulb is somewhere behind your nose, as you might expect. This is sub-optimal for ultrasound because your nose isn’t flat, and it is full of air. Packing a subject’s nose with gel wasn’t going to win many fans. The answer was to place the transducer on the person’s forehead and shoot down at the bulb. They made a custom headset that let them precisely target areas of the subject’s bulb guided by an MRI.

So far, they have a sample size of two, but they’ve managed to induce the smell of fresh air, garbage, ozone, and burning wood. What would you do with this? Smell-o-vision? A garbage truck VR game? Let us know in the comments. We don’t think this is exactly how the last VR smell gadget we saw worked, but — honestly — we aren’t completely sure.

A 3D-printed assembly standing on short legs is visible. A portion extends upward with the word "Nord" sunk into it. Cables extend from one side of the upright portion, and a side view of a circuit board is visible at the front of the assembly.

Measuring Earth’s Rotation With Two Gyroscopes

November 23, 2025 by Aaron Beckendorf 43 Comments

We’ve probably all had a few conversations with people who hold eccentric scientific ideas, and most of the time they yield nothing more than frustration and perhaps a headache. In [Bertrand Selva]’s case, however, a conversation with a flat-earth believer yielded a device that uses a pair of gyroscopes to detect earth’s rotation, demonstrating that rotation exists without the bulkiness of a Foucalt pendulum.

[Bertrand] built his apparatus around a pair of BMI160 MEMS gyroscopes, which have a least significant bit for angular velocity corresponding to 0.0038 degrees per second, while the earth rotates at 0.00416 degrees per second. To extract such a small signal from all the noise in the measurements, the device makes measurements with the sensors in four different positions to detect and eliminate the bias of the sensors and the influence of the gravitational field. Before running a test, [Bertrand] oriented the sensors toward true north, then had a stepper motor cycle the sensors through the four positions, while a Raspberry Pi Pico records 128 measurements at each position. It might run the cycle as many as 200 times, with error tending to decrease as the number of cycles increases.

A Kalman filter processes the raw data and extracts the signal, which came within two percent of the true rotational velocity. [Bertrand] found that the accuracy was strongly dependent on how well the system was aligned to true north. Indeed, the alignment effect was so strong that he could use it as a compass.

In the end, the system didn’t convince [Bertrand]’s neighbor, but it’s an impressive demonstration nonetheless. This system is a bit simpler, but it’s also possible to measure the earth’s rotation using a PlayStation. For higher precision, check out how the standards organizations manage these measurements.

Deep Fission Wants To Put Nuclear Reactors Deep Underground

November 23, 2025 by Maya Posch 77 Comments

Today’s pressurized water reactors (PWRs) are marvels of nuclear fission technology that enable gigawatt-scale power stations in a very compact space. Though they are extremely safe, with only the TMI-2 accident releasing a negligible amount of radioactive isotopes into the environment per the NRC, the company Deep Fission reckons that they can make PWRs even safer by stuffing them into a 1 mile (1.6 km) deep borehole.

Their proposed DB-PWR design is currently in pre-application review at the NRC where their whitepaper and 2025-era regulatory engagement plan can be found as well. It appears that this year they renamed the reactor to Deep Fission Borehole Reactor 1 (DFBR-1). In each 30″ (76.2 cm) borehole a single 45 MWt DFBR-1 microreactor will be installed, with most of the primary loop contained within the reactor module.

As for the rationale for all of this, at the suggested depth the pressure would be equivalent to that inside the PWR, with in addition a column of water between it and the surface, which is claimed to provide a lot of safety and also negates the need for a concrete containment structure and similar PWR safety features. Of course, with the steam generator located at the bottom of the borehole, said steam has to be brought up all the way to the surface to generate a projected 15 MWe via the steam turbine, and there are also sampling tubes travelling all the way down to the primary loop in addition to ropes to haul the thing back up for replacing the standard LEU PWR fuel rods.

Whether this level of outside-the-box-thinking is a genius or absolutely daft idea remains to be seen, with it so far making inroads in the DoE’s advanced reactor program. The company targets having its first reactor online by 2026. Among its competition are projects like TerraPower’s Natrium which are already under construction and offer much more power per reactor, along with Natrium in particular also providing built-in grid-level storage.

One thing is definitely for certain, and that is that the commercial power sector in the US has stopped being mind-numbingly boring.