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Marmosets are the first non-human primates shown to use personalised signifiers to refer to each other – the discovery could help us better understand how language evolved

Digging in the ground is so commonplace on Earth that we hardly ever think of it as hard. But doing so in space is an entirely different proposition. On some larger worlds, like the Moon or Mars, it would be broadly similar to how digging is done on Earth. But their “milligravity” would make the digging experience quite different on the millions of asteroids in our solar system. Given the potential economic impact of asteroid mining, there have been plenty of suggested methods on how to dig on an asteroid, and a team from the University of Arizona recently published the latest in a series of papers about using a customized bucket wheel to do so.

Bucket wheel designs seem to be gaining popularity in space mining more generally lately. NASA’s ISRU Pilot Excavator (IPEx) uses a similar design and has been advanced to Technology Readiness Level 5, according to its latest yearly report. However, it was designed for use on the Moon, where gravity is significantly larger than that of the asteroids that hold vastly more valuable materials.

According to the paper, the lowest 10% of asteroids have higher concentrations of platinum group metals, such as palladium and osmium, than the Moon does. They are also much more “energy accessible,” meaning that you would only need a delta-V of about 5% that of the Moon to get resources off an asteroid undergoing active mining. Since delta-V is equivalent to fuel weight and is therefore directly equivalent to cost, lower delta-V makes mining on these tiny bodies much more economically attractive.

This video, from nine years ago, shows how long the development path for asteroid mining technology is.

But they have their own engineering challenges to face. Most asteroids are known as “rubble piles,” meaning they are made up of clumps of rock simply stuck together by whatever minimal gravity their mass gives them. Even metal-rich M-type asteroids, such as Psyche, could be primarily composed of these small chunks of material. Such an environment would not be very hospitable to traditional mining techniques.

The University of Arizona researchers, led by Dr. Jekan Thangavelautham, have taken a rapid iteration approach to solving that problem. They developed a model representing the forces expected on the surface of an asteroid and applied those forces to models of different bucket wheel designs, selecting features that best suit the environment.

They also took the next step and started 3D printing prototypes of the different designs. They intended to use those printed prototypes to collect physical data on the mechanics of excavation; however, to do so, they needed realistic asteroid regolith simulant material. That doesn’t currently exist, so they decided to make their own. A combination of styrofoam and 3D-printed resin seemed to do the trick, however they weren’t able to make enough simulant yet to test a planned test assembly for this paper thoroughly.

Artist’s depiction of an implementation of a bucket wheel excavator
Credit – Hansen, Muniyasamy, & Thangavelautham

One of the other important findings of the paper was the impact different characteristics of the asteroid itself would have on two of the most important parameters for the design—the bucket volume and the cutting velocity (i.e., how fast the buckets move). Some characteristics, such as the resource concentration, had little impact on those two parameters. However, other obvious ones, such as the density, had a major impact. 

The research team found that high-volume, slow-moving buckets were ideal in this environment. However, part of that consideration was how quickly an orbiting support craft would fill up with material being excavated. To increase the throughput time of material from the bucket wheel to the storage system, the researchers suggest the use of a screw feeder, which would also allow the bucket to operate continuously – another necessity given the economic constraints of the system.

Additionally, they found that claws were necessary to hold onto the regolith. An extensible tubing system is also a “nice-to-have,” though it becomes more necessary if there are many buckets per wheel.

Details of this work are contained in the paper, and an associated presentation was given by the researchers at the ASCEND conference at the end of July. While these milestones are a step in the right direction, these technologies are still at a relatively low readiness level. However, they will eventually be needed if humans utilize some of the most easily accessible resources in the solar system. As our expansion to other worlds picks up, it’s only a matter of time before a bucket excavator lands on an asteroid and starts going to work.

Learn More:
Hansen, Muniyasamy, & Thangavelautham – Modified Bucket Wheel Design and Mining Techniques for Asteroid Mining
UT – Heavy Construction on the Moon
UT – A Handy Attachment Could Make Lunar Construction a Breeze
UT – Robotic asteroid mining spacecraft wins a grant from NASA

Lead Image:
Artist’s depiction of NASA’s IPEx Bucket Excavator Robot.
Credit – NASA

The post What Type of Excavator Is Most Suitable for Asteroids? appeared first on Universe Today.

Chemists have developed a method to furnish a range of molecules with a trifluoromethyl group attached to a sulfur, nitrogen or oxygen atom. Their procedure avoids the use of PFAS reagents. It thus provides an environmentally friendly synthesis route for pharmaceutical and agrochemical compounds that rely on the presence of the trifluoromethyl group.

Chemists have developed a catalytic process that turns the largest component of today's plastic waste stream, polyolefin plastic bags and bottles, into gases -- propylene and isobutylene -- that are the building blocks of polypropylene and other types of plastics. The process uses inexpensive solid catalysts that can be scaled to industrial production, making this a potentially viable means of creating a circular economy for these throw-away plastics.

Researchers have developed a prototype for a smart mask that can be used to monitor a range of medical conditions, including respiratory ailments, such as asthma, COPD (chronic obstructive pulmonary disease), and post-COVID-19 infections.

Researchers have developed a prototype for a smart mask that can be used to monitor a range of medical conditions, including respiratory ailments, such as asthma, COPD (chronic obstructive pulmonary disease), and post-COVID-19 infections.

Wildfires can damage crops, even if flames come nowhere near the plants. One outcome can be an unpleasant flavor and smell of wine that is made from grapes exposed to smoke. But researchers say that they have developed a way to lessen this smoke taint to improve the palatability of the wine.

Testing for levels of microplastic contamination in marine plankton aims to help develop new ways to assess and manage the rising global pollution problem, experts say. Researchers examined the effects of five different chemical digestive aids on common plastics using low, medium and high levels of zooplankton.

Synchronizing periodic excitations of photocatalysts with a Michelson interferometer on operando FT-IR spectroscopy, researchers succeeded in observing and identifying the reactive electron species for photocatalytic hydrogen evolution. In contrast to the traditional belief, this study demonstrates that not the free electrons in metal cocatalysts but the electrons trapped in the periphery of cocatalysts directly contribute to the photocatalysis.

Scientists have made a significant leap forward in the field of chiral molecules. The team achieved near-complete separation in quantum states for these essential components of life.

Scientists have made a significant leap forward in the field of chiral molecules. The team achieved near-complete separation in quantum states for these essential components of life.

To understand the mysteries surrounding black holes, researchers at Tohoku University have created a simulation of accretion disk turbulence that possesses the highest-resolution currently available.

Researchers resent a new molecule for visualizing the sphingomyelin metabolism. This offers prospects for innovative therapeutic approaches in infection research.

Immersive virtual reality could open up a whole new world for people with intellectual disability, enabling them to learn practical life skills much faster without relying on caregivers, according to a new study.

Researchers created a new quantum state of matter, dubbed a higher-order topological magnet, that may address key issues in quantum technology.

A collaborative research team has identified the world's first multiple Majorana zero modes (MZMs) in a single vortex of the superconducting topological crystalline insulator SnTe and exploited crystal symmetry to control the coupling between the MZMs. This discovery offers a new pathway to realizing fault-tolerant quantum computers.

It's not easy being green. Scientists for years have made small red and blue lasers, but other colors, including green, have been a challenge. A team has now filled this technology gap by creating orange, yellow and green lasers tiny enough to fit on a chip, opening up a wide range of applications in quantum sensing, communications and information processing.

Researchers have developed a pioneering technique for producing large-scale graphene current collectors. This breakthrough promises to significantly enhance the safety and performance of lithium-ion batteries (LIBs), addressing a critical challenge in energy storage technology.

After about 10 years of construction, the Vera Rubin Observatory (VRO) is scheduled to see its first light in January 2025. Once it’s up and running, it will begin its Legacy Survey of Space and Time (LSST), a decade-long effort to photograph the entire visible sky every few nights. It’ll study dark energy and dark matter, map the Milky Way, and detect transient astronomical events and small Solar System objects like Near Earth Objects (NEOs).

New research shows the LSST will detect about 130 NEOs per night in the first year of observations.

NEOs are small Solar System bodies, usually asteroids, that orbit the Sun and come within 1.3 astronomical units of the Sun. When a NEO crosses Earth’s orbit at some point, it’s considered a potentially hazardous object (PHO). NASA is currently cataloguing NEOs, and while they’ve made progress, there are many more left to find.

According to new research, the upcoming LSST will detect about 130 NEOs per night. The research is “Expected Impact of Rubin Observatory LSST on NEO Follow-up,” and it’s still in peer-review but available on the prepress site arxiv.org. The lead author is Tom Wagg, a PhD student at the DiRAC Institute and the Department of Astronomy at the University of Washington in Seattle.

“We simulate and analyze the contribution of the Rubin Observatory Legacy Survey of Space and
Time (LSST) to the rate of discovery of Near Earth Object (NEO) candidates,” the authors write. They also analyzed submission rates for the NEO Confirmation Page (NEOCP) and how that will affect the worldwide follow-up observation system for NEOs.

The problem with NEOs is that they don’t necessarily remain NEOs. A subset of them—about one-fifth—pass so close to Earth that even a small perturbation can send them on an intersecting path with Earth’s orbit. These are sources of potentially catastrophic collisions. A further subset of these are called Potentially Hazardous Asteroids (PHAs), and they’re massive enough to make it through Earth’s atmosphere and strike the planet’s surface. To be considered a PHA, an object has to be about 140 meters in diameter.

The Minor Planet Center maintains a database of NEOs, and more are being added constantly. New detections are recorded on the NEO confirmation page (NEOCP), but at first, they’re only candidates. Follow-up observations require resources to accurately determine a candidate’s orbit and size.

If the LSST contributes 130 more NEO detections each day, which is eight times the current detection rate, the survey will create an enormous amount of follow-up work. According to a standard computer algorithm named digest2 that evaluates them, NEOs are only considered candidates if they meet certain criteria, and that can only be determined by follow-up observations with other telescopes.

Illustration of a Near Earth Object. Credit: NASA/JPL-Caltech

But with so many more detections on the horizon, there could be problems.

“The aim of this paper is to quantify the impact of Rubin on the NEO follow-up community and consider possible strategies to mitigate this impact,” the authors write.

Most of the NEOs the LSST finds will be found using a method called “tracklet linking.” Tracklet linking is “a computational technique where at least three pairs of observations (“tracklets”) observed over a 15-night period are identified as belonging to the same object,” the authors explain. The problem is that the tracklet linking can take time and comes at a cost. “… the object is not identified as interesting until the third tracklet is imaged – at best, two nights after the first observation or, at worst, nearly two weeks later,” the authors write. This means that the system may miss interesting or hazardous objects until it’s too late to observe them for confirmation.

With other telescopes, there’s a way around this. They can capture several back-to-back images of tracklets to create more robust detections that can be immediately followed up on. However, the VRO can’t do that because the LSST is an automated survey.

What it can do is serendipitously capture three or more tracklets in smaller sections of the sky where its observing fields will overlap. “Such tracklets could be immediately identified and, assuming they meet the digest2 score criteria, submitted to the Minor Planet Centre and included on the NEOCP,” the authors write. Because of the scale, the authors say this process could be automated and would require no human vetting.

The researchers simulated LSST detections to test their idea and see if it could reduce the follow-up observation workload. “We present an algorithm for predicting whether LSST will later re-detect an object
given a single night of observations (therefore making community follow-up unnecessary),” they explain. They wanted to determine how effective it would be in reducing the number of objects that require follow-up observations.

They started by simulating almost 3600 days of the LSST, consisting of almost one billion observations.

This figure from the study shows the number of asteroids detected in one night of LSST simulations. About 350,000 asteroids were observed, including about 1,000 NEOs. The grey curved line represents the ecliptic. Image Credit: Wagg et al. 2024.

From their data, they selected observations that corresponded to tracklets. Single tracklets don’t determine an orbit, but they can constrain potential orbits when compared to known Solar System orbits. The digest2 algorithm works by comparing observed tracklets to a simulated catalogue of Solar System objects to estimate the probability that an object is a NEO. It takes all the data and estimates the possible orbits of the objects.

This figure from the research shows the variant orbits computed for one simulated NEO tracklet. The white arrow indicates the initial sight line for the observation. The blue dotted line indicates the orbit of the Earth. The background stars are included for illustrative purposes only. Image Credit: Wagg et al. 2024.

At this point, the number of candidate NEOs is still overwhelming. The candidate population is not a high-purity sample and still contains non-NEOs like main-belt asteroids.

Most of the impurity is caused by main-belt asteroids, and as these were recognized, the purity would rise. The simulations show that purity would continually rise, and after about five months, it would level off. A similar thing happens with submission rates. After about 150 nights, the submission rate reaches a steady state of about 95 per night.

The LSST repeatedly images the sky in overlapping fields. The researchers thought that if they could determine which tracklets were going to be re-observed by the LSST as it goes about its business, they could reduce the follow-up observation burden.

“If we could predict which objects will be followed up by LSST itself, this would reduce the load on the follow-up system and allow the community to focus on the ones that truly require external follow-up to be designated,” the authors explain. The researchers developed an algorithm for computing the ensemble of ranges and radial velocities of a single observed tracklet.

“We now examine the effect of applying the LSST detection probability algorithm to reduce the load on the NEOCP,” the authors write. The following image illustrates this.

This figure from the research shows the estimated probability of detection by the algorithm and the number of objects, with the dotted black line being the threshold for confirmation. On the right is a contingency matrix with two Truth columns and two Prediction rows. All in all, it shows that the algorithm detected 180 NEOs, with 400 being sent for confirmation needlessly, as the LSST will have confirmed them. Lost objects are objects that have been de-prioritized for follow-up observations but won’t receive adequate follow-ups by the Rubin itself. Image Credit: Wagg et al. 2024.

Overall, the algorithm predicted the correct outcome 68% of the time. Also, about 64 of the objects submitted to the NEOCP per night would require external follow-up, but only around 8.3%, or about five, of those objects would be NEOs. The algorithm would only improve accuracy minimally, but it would reduce the follow-up workload by a factor of two.

The researchers say that other tweaks to the algorithm can improve it and make LSST NEO detections more robust without the need for so many demanding follow-up observations.

In their conclusion, the authors write, “LSST contributions will increase the nightly NEOCP submission rate
by a factor of about 8 over the first year to an average of 129 objects per night.” However, the fraction that will be confirmed is low at about 8.3%, but will rise over time.

The LSST is expected to generate 200 petabytes of uncompressed data during its ten-year run, which is about 200 million gigabytes. This study shows that managing the amount of data that the LSST will generate requires new methods.

It may seem like a far-away concern, but understanding the threat to Earth posed by NEOs is critical. While efforts are being made to understand how we can protect the planet from them, cataloguing them all is important.

The post The Rubin Observatory Will Unleash a Flood of NEO Detections appeared first on Universe Today.

The largest sailing cargo ship in existence is on its maiden voyage across the Atlantic Ocean, demonstrating a carbon footprint 10 times smaller than that of a container ship