Science News March 22

[This is a transcript with references.]

Welcome everyone to this week’s science news. Today we’ll talk about a new comet, drone deliveries, how the hydrogen economy could actually make global warming worse, a better way to control spin qubits, modular robots that could work on the moon, soft crystals, how to turn a phone into a fluorescent microscope, and of course, the telephone will ring.

Two teams of astronomers have independently discovered a new comet that might be prominently visible up in the sky next year.

The comet was first spotted in January by astronomers at the Purple Mountain Observatory in China. They named it C 2023 A3 which makes me feel much better about Hossenfelder.

Then last month, one of the telescopes of NASA’s asteroid tracking system ATLAS, the one in South Africa also saw the comet during its night scan. This is an animation of all the asteroids that NASA is keeping an eye on, it’s really quite a lot!

But a comet is not an asteroid. A comet is an icy body – think, snowball – in orbit around the Sun. When it gets near the sun it warms up and that releases gases which light up. Its name comes from the Greek phrase for “long-haired star,” because those gases often look like a tail. This for example is the comet C 2002 V1 in an image from 2003.

The new comet is currently about a billion kilometres away from us. At the moment, it’s hurtling through the orbits of Jupiter and Saturn at about 15 point 7 kilometres a second. It probably came from the Oort cloud. That’s a shell of icy debris beyond the orbit of Pluto, that was left over from the creation of our solar system.

Astronomers think this new comet could become spectacularly bright. For one thing, it’s already bright for something so far away, and also, its orbit makes it likely that it’ll become even brighter. This is the orbit it’s predicted to take. As you can see, the comet is going to come pretty close both to the sun and to Earth. When it gets close to the sun, its gases should really heat up and put on a display.

According to this prediction, the closest encounter to the sun will be on September 27, 2024. Two weeks after that, in mid-October next year, it will pass by our planet,just 70 million kilometres away. It should be easy to see.

Some comets are quite a sight, like Comet West was in March 1976. But not all put on a show as expected. Some comets flare off earlier than predicted, others fall apart before they really shine, and maybe that’s also where the word “comment” comes from.

The silicon valley-based company Zipline has unveiled a two-step drone delivery system that saves time, noise, and carbon emissions.

The Zipline system features a fleet of fixed-wing drones – Zips – that fly about 100 meters above the ground, almost silently. When they get to their destination, they hover and drop a smaller delivery drone – attached by tether – down to a patio or front step. The smaller drone drops off the package, say food or a prescription, pulls itself back up to the big one, and returns home.

The Zip has to dock and recharge when it gets home but it can travel 16 kilometres in 10 minutes, that’s about seven times faster than the average car delivery. It can carry up to three kilograms.

One of the customers of this new delivery system is Sweetgreen, the healthy salad company. It says the Zips can save 97 percent of the fossil fuel emissions that car deliveries would take.

The U2 singer Bono is on Zipline’s board, and currently working on his new song “I Still Haven’t Found That Drone I’m Looking For.”

A team of researchers from Princeton has calculated that leaks from the emerging hydrogen economy could make global warming worse.

Hydrogen is seen by many as a critical part of decarbonizing the economy. It’s supposed to be a flexible, low-carbon replacement for fossil fuels. It comes in particularly handy for purposes where energy supply is hard to electrify, like shipping, air transport and heavy industry.

More than 20 countries have launched large-scale hydrogen production programs as part of their climate strategies already. By 2050, hydrogen is supposed to replace about 15 percent of the energy presently derived from fossil fuels. The idea of a hydrogen economy has some problems which I talked about in a previous video, but the new paper raises an issue I hadn’t heard of before.

It’s that some of the hydrogen leaks into the atmosphere, either during production, storage, or incomplete combustion. The fraction of hydrogen that leaks can be substantial. Exact numbers are hard to come by, but estimates say it’s between 0 point 1 and as much as ten percent of the produced hydrogen that leaks into the atmosphere.

The issue hasn’t received much attention so far, because hydrogen is neither a greenhouse gas nor a pollutant. But the authors of the new paper point out that hydrogen links to the methane cycle, and methane is a greenhouse gas.

They say that more hydrogen gas in the atmosphere can reduce the amount of the radical hydroxide. And hydroxide removes methane from the atmosphere, so less hydroxide means more methane. More hydrogen could also increase the amount of ozone in the troposphere which also acts as a greenhouse gas.

In their paper the authors calculate the contribution that hydrogen production makes to methane in the atmosphere, assuming we do replace 15 percent of fossil fuels, as the plans have it. The consequences depend on how the hydrogen is produced because some of the production methods also leak methane. They compare green hydrogen, that would be produced by renewables, with blue hydrogen that is produced from methane with carbon capture and storage, with different assumptions about the amount of methane leaks.

You see the results in this figure. The horizontal axis shows the percentage of hydrogen that leaks. The vertical axis is the carbon dioxide equivalent. For reference, the amount of carbon dioxide in the atmosphere currently increases by about 2 point 5 ppm per year. The green and blue bars are the results for green hydrogen and blue hydrogen with different fractions of methane leak. Those thin grey lines are the case with zero hydrogen leaks. For green hydrogen, it’s at about 9 percent of leakage that it actually begins to contribute to global warming. Blue hydrogen basically always contributes.

They say that if we were to replace 100 percent of fossil fuels with blue hydrogen, then the carbon dioxide equivalent from the leaks could be as much as half of the entire increase since preindustrial times. Keep on dusting those solar panels guys.

Mr President,

Six million tons of seaweed. Well, that’s better than no tourists.

Sure, let me think. You could eat it, if it’s fresh. You could make T-shirts from it. Ah, I know, camouflage for the military! Veni Weedy Vici!

Always at your service.

HRL Laboratories has announced the first demonstration of universal control of encoded spin qubits, a step that could advance the field of quantum computing.

HRL Laboratories is a private research and development consultancy. They’re located in California and owned by the Boeing Company and General Motors. For their new experiment, they custom-made a silicon device with metallic gates, like little jail cells. In those, they trapped six electrons in a line. They then used voltage pulses to entangle the electrons, rather than the more commonly used microwaves. They hope this will reduce the errors that currently hold back quantum computing from commercial viability.

In this experiment, they entangled the electrons in three sets of two pairs. Then they led them through a sort of electronic dance during which each in a pair partially swapped the spin state of its partner. They then showed that the quantum properties were maintained.

All this electronic dancing happened in less than a ten thousandth of a second, which is not a lot of time, but I’m sure nightcore will soon get there.

The demonstration follows an announcement earlier this month from Google’s Quantum AI team that it had achieved scalable error correction. Though they might have been better off investing into error correction for their Chatbot.

A team of student engineers at MIT has invented a snap-together modular robot system, called WORMS for performing heavy tasks at a future moon base. Yes, I know you wonder why it’s named after a German city. You’ll be surprised to hear it’s not, it’s an acronym that stands for “Walking Oligomeric Robotic Mobility System” and oligomeric is more Greek, it means with few parts.

They developed the prototype in response to NASA’s Big Idea Challenge. That’s an annual competition for university students. Last year’s challenge was to invent a robotic system that can move across extreme terrain without wheels. According to the MIT press release, the students had the idea for WORMs by thinking about a goat tethered to an ox, which makes about as much sense as I expect engineers to make.

But you’ll see what they mean if you look at what they did. WORMS is a carrying platform with many arms that look like worms that can be equipped with different tools. You can see some of the components here. Here’s the worm-like limb. The carrying platform. The wok-like foot. And the snap-together couplers. The prototype also had a sort of head with a LiDAR and a communications system. The robots are easy to assemble and reconfigure, and have a reasonable chance to work even in the more dusty regions of the moon and when assembled in astronaut suits.

Last week, the team presented WORMs at the Aerospace Conference of the IEEE and won its best paper award. According to team leader George Lordos: “You could imagine a shed on the moon with shelves of worms.” I’ll just leave you with that thought.

NASA has put out a map that shows a year’s worth of cosmic gamma rays as they strike Earth.

The purple pulses are the changes in the brightness of the gamma rays. The yellow orb is the trajectory of the sun across the sky. And this orange belt around the middle is the central plane of the Milky Way, which emits gamma rays pretty steadily.

Gamma rays are electromagnetic radiation, just like visible light, but they have shorter wavelengths and higher energies, even higher than x-rays. Most of these that you’re seeing here – about 90 per cent – came from blazars, that are huge, directed blasts of energy from supermassive black holes in other galaxies.

The others may have come from collisions of neutron stars or supernovae. Researchers are interested in gamma ray bursts because they give us clues about how stars form and evolve. At least that’s what they say. I think they’re interested in gamma ray bursts because each of those harmless looking flickers would easily have wiped out life on earth if it had happened nearby and they just like the horror of thinking about that.

The animation is based on observations from February 2022 to February 2023 by the Large Area Telescope. It’s part of NASA’s Fermi Gamma-ray Space Telescope and sees the universe in gamma rays, scanning the whole sky every three hours.

The gamma ray background is unofficially being referred to as “space fireworks.” But please don’t try it at home, as it may lead to a loss of your space fingers.

A Dutch team of materials scientists and physicists has discovered a crystal that becomes soft and squishy. It’s a type of salt that absorbs water from the air and does, well, weird things.

Some crystals, such as table salt absorb water from the air and start to partly dissolve and clump together. This process is called “deliquescence” and is the reason why your grandma put rice into the saltshaker. Here you see what happens to the salt when it gets in contact with water.

But a salt called mirabilite doesn’t do that. It’s also known as Glauber’s salt and famous for its laxative properties, though famous probably isn’t the best word here. It’s interesting because hydrated salts such as mirabilite are abundant on Earth and even present on Mars. Scientists are investigating them for example for their potential as thermal energy storage.

The authors of the new paper used spectroscopy combined with microscopes to figure out what’s going on with this Glauber salt. They discovered that rather than just dissolving from the outside like table salt, it builds some of the water into its interior where it, however, maintains some of its crystal structure despite the water. If left to dry later, it crystallizes again, though in a different chemical form.

Not only that, but the surfaces of those soft crystals were so flexible they could heal themselves from holes or indentations. You can see it here if you look at the bottom of the screen. The black bit is being expelled by the microcrystal and then the edge reforms itself. Chemistry is wild.

A group of biologists at Winona State University in Minnesota has developed a cheap, easy way to turn your smartphone into a fluorescence microscope. They are calling it a glowscope.

A fluorescence microscope uses a light source that excites fluorescent molecules in the sample. The molecules absorb the light and then emit it back, usually at somewhat longer wavelengths. The microscope then collects the emitted light. Fluorescence microscopes are useful among other things because they let you look inside cells. But these microscopes typically cost thousands of dollars.

The biologists from Minnesota now found a way to build a basic fluorescence microscope from parts that cost less than 50 dollars. They used a blue LED flashlight, a piece of Plexiglas, second-hand theatre stage-light filters, and clip-on lenses for amateur photography. It’s easy to handle, assemble, and set up, and could be used for example in schools or field work.

The team conducted a few simple experiments on zebrafish embryos to show how the device works. Here you see the beating hearts of three-day-old zebrafish embryos whose heart cells produce a green fluorescent protein. And here, you can see that acidic water makes the embryos’ heart rate slow down.

Their paper includes a how-to section on which filters and LED lights to use so that the smartphone can pick up either green or red fluorescence. Which raises the interesting question: If a student is caught using their smartphone during English class doing science, should they or should they not be required to recite Shakespeare in Greek?