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An artificial intelligence could gauge what characters and locations people were viewing in the film (500) Days of Summer based on the activity of their neurons

Researchers have created a new, cost-effective training technique for artificial intelligence systems that aims to make them less socially biased.

Researchers have created a new, cost-effective training technique for artificial intelligence systems that aims to make them less socially biased.

Scientists predict the existence of flat electronic bands at the Fermi level, a finding that could enable new forms of quantum computing and electronic devices.

Scientists predict the existence of flat electronic bands at the Fermi level, a finding that could enable new forms of quantum computing and electronic devices.

Scientists are helping to develop standards and safety protocols that would allow pharmacies to print drugs onsite at a dosage best for you.

Computers have come so far in terms of their power and potential, rivaling and even eclipsing human brains in their ability to store and crunch data, make predictions and communicate. But there is one domain where human brains continue to dominate: energy efficiency.

More than 100,000 oil and gas wells across the western U.S. are in areas burned by wildfires in recent decades, a new study has found, and some 3 million people live next to wells that in the future could be in the path of fires worsened by climate change.

Solar physicists have revealed the interior structure of the sun's supergranules, a flow structure that transports heat from the sun's hidden interior to its surface. The researchers' analysis of the supergranules presents a challenge to the current understanding of solar convection.

Researchers have succeeded in directing floating objects around an aquatic obstacle course using only soundwaves. Their novel, optics-inspired method holds great promise for biomedical applications such as noninvasive targeted drug delivery.

If aliens modified a planet in their solar system to make it warmer, we'd be able to tell. A new study identifies the artificial greenhouse gases that would be giveaways of a terraformed planet.

Researchers have found a way to bind engineered skin tissue to the complex forms of humanoid robots. This brings with it potential benefits to robotic platforms such as increased mobility, self-healing abilities, embedded sensing capabilities and an increasingly lifelike appearance. Taking inspiration from human skin ligaments, the team included special perforations in a robot face, which helped a layer of skin take hold.

Researchers have found a way to bind engineered skin tissue to the complex forms of humanoid robots. This brings with it potential benefits to robotic platforms such as increased mobility, self-healing abilities, embedded sensing capabilities and an increasingly lifelike appearance. Taking inspiration from human skin ligaments, the team included special perforations in a robot face, which helped a layer of skin take hold.

Researchers have developed a new method for detecting foodborne pathogens that is faster, cheaper, and more effective than existing methods. Their microfluidic chip uses light to detect multiple types of pathogens simultaneously and is created using 3D printing, making it easy to fabricate in large amounts and modify to target specific pathogens. The researchers hope their technique can improve screening processes and keep contaminated food out of the hands of consumers.

Researchers have developed a new method for detecting foodborne pathogens that is faster, cheaper, and more effective than existing methods. Their microfluidic chip uses light to detect multiple types of pathogens simultaneously and is created using 3D printing, making it easy to fabricate in large amounts and modify to target specific pathogens. The researchers hope their technique can improve screening processes and keep contaminated food out of the hands of consumers.

If liquid water exists today on Mars, it may be too deep underground to detect with traditional methods used on Earth. But listening to earthquakes that occur on Mars -- or marsquakes -- could offer a new tool in the search.

Deducing the correct pattern that links pairs of coloured grids is relatively easy for most people, but relies on skills that artificial intelligence models lack. A new $1 million prize hopes to encourage the development of an AI that can solve such puzzles

Our arm of the Milky Way is filled with older, metal-rich stars. New research suggests these might provide the best conditions for life to form on their planets

If the Sun has a stellar neighbourhood, it can be usefully defined as a 20 parsec (65 light-years) sphere centred on our star. Astronomers have been actively cataloguing the stellar population in the neighbourhood for decades, but it hasn’t been easy since many stars are small and dim.

Even with all of the challenges inherent in the effort, astronomers have made steady progress. Do we now have a complete catalogue?

In a new article in Research Notes of the American Astronomical Society, a pair of researchers from the Leibniz Institute for Astrophysics in Potsdam, Germany, try to understand how complete or incomplete our catalogue of the stellar neighbourhood is. The article is titled “Do We Finally Know all Stellar and Substellar Neighbors within 10~pc of the Sun?” The authors are Ralf-Dieter Scholz and Alexey Mints.

If all stars shone as brightly as main sequence stars like our Sun do, it would be easy to catalogue the stars in our neighbourhood. But they don’t. Some are so small and dim that they’re considered failed stars. We call them brown dwarfs or substellar objects.

When we look up at the night sky with the unaided eye, our view is dominated by main sequence stars and giant stars, many of which are far beyond our stellar neighbourhood. Many stars are too dim to see, like red dwarfs and brown dwarfs. In fact, Proxima Centauri, a red dwarf and our nearest neighbour, wasn’t discovered until the early 20th century.

Proxima Centauri. Credit: ESA/Hubble & NASA

In the early days of astronomy, measurements of proper motions showed that some stars that appear fixed in place are closer than other stars. All stars move and have proper motion; it’s just not always noticeable in the span of a single lifetime. High proper motion surveys of stars led to the selection of certain stars for measurements of their parallax, which helped locate more stars correctly in space. Then, in the early 20th century, as astronomy and photography were used in conjunction, photographic astrometry triggered a wave of discoveries of our solar neighbours. Those efforts showed that our nearest neighbours are red dwarfs (M dwarfs).

In the 1990s, as technology advanced, infrared sky surveys found more dim stars. “A second wave of discoveries started in the late 1990s with the advance of infrared sky surveys,” the authors write. Missions like the Two Micron All-Sky Survey (2MASS) gave us a new, unprecedented look at the sky. It found M dwarfs, brown dwarfs, and substellar objects like L, T, and Y types, and even minor planets in the Solar System. (Definitions of brown dwarfs and other substellar objects overlap.) By the year 2,000, the Sloan Digital Sky Survey came online, strengthening our catalogue of the sky.

In 1997, Henry et al. published an important paper on the solar neighbourhood titled “The solar neighborhood IV: discovery of the twentieth nearest star.” It showed that the discovery of LHS 1565, about 3.7 pc from Earth, spelled trouble for our census of the neighbourhood. “It ranks as the twentieth closest stellar system and underscores the incompleteness of the nearby star sample, particularly for objects near the end of the main sequence,” Henry et al. wrote. “Ironically, this unassuming red dwarf provides a shocking reminder of how much we have yet to learn about even our nearest stellar neighbours.”

Since about 1997, there’s been a burst of discoveries of stars within the Sun’s neighbourhood. The authors say that these seem to have filled in the gaps in our 10 pc neighbourhood. But some of the knowledge was still based on two assumptions. The first was that the survey out to 5 parsecs was complete, and the second was that the density was uniform out to 10 parsecs. “The first of these is not true, and the second is in question,” the authors write.

Where does that leave us? Up to 90 star systems could still be missing.

An artist’s conception of a brown dwarf. Brown dwarfs are more massive than Jupiter but less massive than the smallest main sequence stars. Their dimness and low mass make them difficult to detect. Image: By NASA/JPL-Caltech (http://planetquest.jpl.nasa.gov/image/114) [Public domain], via Wikimedia Commons

“Using all neighbours the luminosity and mass functions and the star-to-brown dwarf (BD) number ratio can be studied,” the authors state. Astronomers don’t fully understand the ratio of brown dwarfs to other stars, but two recent papers (1,2), in particular, have continued the work to better understand and catalogue our stellar neighbourhood’s dim members.

Earlier this year, Kirkpatrick et al. published a study claiming that a complete survey of nearby stars is possible, largely thanks to Gaia data. They found 462 objects (including the Sun) in 339 systems within 10?pc. of the Sun.

In previous work, the authors of this new paper added 16 more stars to the list. These were late M-dwarfs, some of the coolest and dimmest main sequence stars, and brown dwarfs. They also discovered a new white dwarf companion to an existing M dwarf.

But how complete is this newest survey?

The problem lies in the difficulty of detecting dim stars like brown dwarfs and late M-dwarfs. The further we look, the more difficult they are to detect. They’re also more difficult to detect in the direction of the galactic plane.

Dim objects like brown dwarfs are more difficult to detect when looking toward the galactic plane because that’s where most of the Milky Way’s mass is. Image Credit: ESA/Gaia/DPAC

The authors say that our neighbourhood stellar catalogue is still likely missing 93 stellar systems, “… corresponding to a deficit of ?21.5%,” they write. In terms of individual stars, it’s not much better: “…138 missing objects corresponding to a deficit of ?23.0%,” they write.

They broke it down even further to individual star types. We’re probably missing 28.1% of AFGK stars, -31% of white dwarfs, and ?27.8% of M-dwarfs. There’s also a higher deficit for late M-dwarfs. These deficits are higher than expected. What does it mean?

“The estimated deficits of systems and individual objects within 10?pc exceed expectations, in particular for the well-known AFGK stars,” the authors write. They conclude that the general assumption of a constant stellar density in the solar neighbourhood is incorrect. They say that small-scale density fluctuations can at least partly explain the deficits.

“Our statistical estimates show that the probability of these discrepancies being caused by random fluctuations is around 40%,” the authors conclude.

We clearly have more work to do.

The post Do We Now Have an Accurate Map of Nearby Stars? appeared first on Universe Today.

Collecting material from an asteroid seems like a simple task. In reality, it isn’t. Low gravity, high rotational speeds, lack of air, and other constraints make collecting material from any asteroid difficult. But that won’t stop engineers from trying. A team from Beijing Spacecrafts and the Guangdong University of Technology recently published a paper that described a novel system for doing so – using an ultrasonic drill and gas “conveyor belt.”

So far, three missions have successfully taken samples from an asteroid: Hayabusa-1 and -2 and OSIRIS-REx. Both Hayabusa missions used a projectile to impact the asteroid and collected the debris from that impact. OSIRIS-REx used a system called the Touch and Go Sample Acquisition Mechanism (TAGSAM), which touched down briefly on Bennu, the mission’s target asteroid, and then pulled away with a sample of its regolith.

Another mission, Rosetta, attempted a more involved sample collection process that involved anchoring to the asteroid itself. However, its lander, Philae, didn’t successfully attach to the asteroid and never managed to return samples to the Rosetta orbiter. Its collection mechanism known as the Sampling and Drilling Device (SD2) was the most similar to conventional sample collection here on Earth, and utilized a drill.

Fraser and Pamela discuss what all goes into a asteroid sample return mission.

That concept of drilling is at the heart of the new proposed system. It utilizes an ultrasonic drill to break up the regolith into small chunks. It’s pretty standard stuff and nothing to write home about, as robots have been doing so on celestial bodies for decades. However, in this case, the drill is surrounded by a system that utilizes gas to push the tiny grains of dust created by the drill up into a sample collection system.

In the paper, the researchers describe it as a “gas conveyor belt,” which pushes the small particles hard enough to allow them to float in the asteroid’s microgravity environment. According to the authors, the proposed system has several advantages. These include low cost, low power consumption, and adaptability to different sample collection site environments.

Another significant advantage is that the probe that utilizes it doesn’t need to be entirely securely anchored to the asteroid. This was the problem for Philae, but the physics of the ultrasonic drill made it possible for the probe to be lightly tethered to the asteroid without having the system for the probe away from the surface.

Visualization of how the gas and drill work together in the system.
Credit – Zhao et al.

In addition to the modeling and theory behind the development of the system, they also built a prototype. They tried it on various regolith simulants in a vacuum and under pressure. Since the experiment was only on a benchtop, they couldn’t test it in the microgravity environment. The ultrasonic drill, which has a “percussive” function similar to a hammer drill used in construction, made neatly drilled holes in a sample rock on the benchtop.

However, some work remains, including more comprehensive system testing, microgravity, and more theoretical modeling of the system’s efficacy. The authors believe this system could be integrated into China’s upcoming asteroid exploration and sample return missions, which they think will happen soon. If they do, they might get a chance to prove this novel piece of technology and move us one step closer to solving the technical challenge of asteroid sample return.

Learn More:
Zhao et al. – Gas-Driven Regolith-Sampling Strategy for Exploring Micro-Gravity Asteroids
UT – Finally, Let’s Look at the Asteroid Treasure Returned to Earth by OSIRIS-REx
UT – Asteroid Ryugu Contained Bonus Comet Particles
UT – OSIRIS-REx’s Final Haul: 121.6 Grams from Asteroid Bennu

Lead Image:
Images of the prototype drilling system in different test configurations.
Credit – Zhao et al.

The post A Combination Drill and Gas Conveyor Could Simplify Asteroid Extraction appeared first on Universe Today.