A lunar rock brought to Earth nearly half a century ago is revealing new information about the moon’s complex history.
NASA’s Apollo 17 mission left the moon to return to Earth 49 years ago Tuesday (Dec. 14) and humanity hasn’t been back to our natural satellite since. In a new study, researchers examined a moon rock collected by astronauts during Apollo 17. By measuring the composition of the rock, designated “troctolite 76535,” scientists have found patterns that point to a 20-million-year cooling period during the moon’s history, defying previous understanding of lunar evolution.
That was a key takeaway from a conversation between economist Daniel Kahneman and MIT professor of brain and cognitive science Josh Tenenbaum at the Conference on Neural Information Processing Systems (NeurIPS) recently. The pair spoke during the virtual event about the shortcomings of humans and what we can learn from them while building A.I.
Kahneman, a Nobel Prize winner in economic sciences and the author of Thinking, Fast and Slow, noted an instance in which humans use judgment heuristics—shortcuts, essentially—to answer questions they don’t know the answer to. In the example, people are given a small amount of information about a student: She’s about to graduate, and she was reading fluently when she was 4 years old. From that, they’re asked to estimate her grade point average.
Using this information, many people will estimate the student’s GPA to be 3.7 or 3.8. To arrive there, Kahneman explained, they assign her a percentile on the intelligence scale—usually very high, given what they know about her reading ability at a young age. Then they assign her a GPA in what they estimate to be the corresponding percentile.
There they found a rectangular submerged structure that measures 300 metres by 150 metres and may have a correlation with the information that ancient authors provided, however, this new discovery still contends against other proposed theories for the location of the temple.
Archaeologists plan to conduct detailed archaeological surveys of the area (terrestrial and underwater) to determine the chronology and function of each of the detected structures and reconstruct the history of the area.
Combining two forms of sustainable energy into one range-extending propulsion system, Swiss Sustainable Yachts’ clean, quiet catamaran promises to jumpstart a future in which the word “range” becomes obsolete. The 64-footer harnesses solar energy to create its own hydrogen, powering a fuel cell-electric drive to potentially limitless autonomy, so long as the sun is shining and the captain isn’t pushing past cruising speed. The Aquon One might prove the ultimate luxury smart yacht of the sustainable generation.
The Aquon One has a 134-hp fuel cell-powered electric engine in each hull. Swiss Sustainable Yachts (SSY) explains that it opts for hydrogen power because of its light weight as compared to batteries or fossil fuels, long-lasting storage capability and lack of harmful emissions. Also critical to the Aquon One design is hydrogen’s ability to be created sustainably, in this case using a solar-powered electrolyzer that splits hydrogen from desalinated seawater. The 689 square feet (64 sq m) of solar panels covering the Aquon One’s hard-top generate all the electricity needed to develop the hydrogen, which is then stored away in carbon tanks.
The Aquon One does include a small battery bank for short-term energy needs, both for propulsion and onboard electrical usage. The hydrogen, on the other hand, is compressed and designated for longer-term use. SSY claims the hydrogen tanks hold more than 100 times the energy of a full-size modern battery system, offering more range and capability than it would get by expanding the size of its battery.
For the first time in history, a spacecraft has touched the Sun. NASA’s Parker Solar Probe has now flown through the Sun’s upper atmosphere – the corona – and sampled particles and magnetic fields there.
The months-long project demonstrates the physics behind the CPUs we take for granted.
Computer chips have become so tiny and complex that it’s sometimes hard to remember that there are real physical principles behind them. They aren’t just a bunch of ever-increasing numbers. For a practical (well, virtual) example, check out the latest version of a computer processor built exclusively inside the Minecraft game engine.
Minecraft builder “Sammyuri” spent seven months building what they call the Chungus 2, an enormously complex computer processor that exists virtually inside the Minecraft game engine. This project isn’t the first time a computer processor has been virtually rebuilt inside Minecraft, but the Chungus 2 (Computation Humongous Unconventional Number and Graphics Unit) might very well be the largest and most complex, simulating an 8-bit processor with a one hertz clock speed and 256 bytes of RAM.
Stacking transistors could be the next big thing in chips.
IBM and Samsung have announced their latest advance in semiconductor design: a new way to stack transistors vertically on a chip (instead of lying flat on the surface of the semiconductor).
The new Vertical Transport Field Effect Transistors (VTFET) design is meant to succeed the current FinFET technology that’s used for some of today’s most advanced chips and could allow for chips that are even more densely packed with transistors than today. In essence, the new design would stack transistors vertically, allowing for current to flow up and down the stack of transistors instead of the side-to-side horizontal layout that’s currently used on most chips.
Abstract: A central goal of condensed-matter physics is to understand how the diverse electronic and optical properties of crystalline materials emerge from the wavelike motion of electrons through periodically arranged atoms. However, more than 90 years after Bloch derived the functional forms of electronic waves in crystals [1] (now known as Bloch wavefunctions), rapid scattering processes have so far prevented their direct experimental reconstruction. In high-order sideband generation [2–9], electrons and holes generated in semiconductors by a near-infrared laser are accelerated to a high kinetic energy by a strong terahertz field, and recollide to emit near-infrared sidebands before they are scattered. Here we reconstruct the Bloch wavefunctions of two types of hole in gallium arsenide at wavelengths much longer than the spacing between atoms by experimentally measuring sideband polarizations and introducing an elegant theory that ties those polarizations to quantum interference between different recollision pathways. These Bloch wavefunctions are compactly visualized on the surface of a sphere. High-order sideband generation can, in principle, be observed from any direct-gap semiconductor or insulator. We thus expect that the method introduced here can be used to reconstruct low-energy Bloch wavefunctions in many of these materials, enabling important insights into the origin and engineering of the electronic and optical properties of condensed matter.
