Checking Up On Earth’s Sister Planet: NASA’s Upcoming Venus Missions

July 9, 2021 by Maya Posch 36 Comments

Even as we bask in the knowledge that our neighboring planet Mars is currently home to a multitude of still functional landers, a triplet of rovers and with an ever-growing satellite network as well as the first ever flying drone on another planet, our other neighboring planet Venus is truly playing the wallflower, with Japan’s Akatsuki orbiter as the lone active Venusian mission right now.

That is about to change, however, with NASA having selected two new missions that will explore Venus by the end of this decade. The DAVINCI+ and VERITAS missions aim to respectively characterize Venus’ atmosphere and map its surface in unprecedented detail. This should provide us information about possible tectonic activity, as well as details about the Venusian atmosphere which so far have been sorely missing.

Despite Venus being the closest match to our planet Earth, how is it possible that we have been neglecting it for so long, and what can we expect from future missions, including and beyond these two new NASA missions?

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What’s Chia, And Why Is It Eating All The Hard Drives?

July 7, 2021 by Tom Nardi 102 Comments

At this point the average Hackaday reader is likely familiar with so-called “Proof of Work” (PoW) cryptocurrencies, such as Bitcoin, Ethereum, and Dogecoin. In the most basic of terms, these cryptocurrencies allow users to earn money by devoting computational power to the network. Unfortunately, it’s well past the point where your standard desktop CPU is moving enough bits to earn anything worthwhile. Individuals looking to turn a profit have therefore resorted to constructing arrays of high-end graphics cards for the express purpose of “mining” their cryptocurrency of choice.

These miners, combined with ongoing chip shortages, have ravaged the GPU market. Anyone who’s looked at building or upgrading a computer recently will know that new video cards are in short supply, and even old models that would otherwise be considered budget options, are commanding outrageous prices. In an effort to appease their core customers, NVIDIA has even introduced cryptocurrency-specific cards that lack video output. The hope was that professional miners would buy these Cryptocurrency Mining Processors (CMPs) instead of the traditional video cards, freeing up the latter for purchase by gamers. But due to the limited availability and relatively high cost of CMPs, they’ve done little to improve the situation.

Now if you don’t use your computer for gaming, this probably seems like a distant problem. You could even be forgiven for thinking of this as little more than two largely frivolous pursuits at loggerheads with each other. After all, in a community that still holds decades-old Thinkpads as the high water mark in portable computing, a certain ambivalence about cutting edge video cards is perhaps to be expected.

But there’s a new form of cryptocurrency on the rise which threatens more than just the hardcore gamers. With “Proof of Space” (PoS) cryptocurrencies, it’s not about having the fastest CPU or the highest number of GPUs; the commodity being traded is storage space, and the player with the most hard drives wins.

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TerraPower’s Natrium: Combining A Fast Neutron Reactor With Built-In Grid Level Storage

July 6, 2021 by Maya Posch 66 Comments

Most new nuclear fission reactors being built today are of the light water reactor (LWR) type, which use water for neutron moderation into thermal neutrons as well as neutron capture. While straightforward and in use since the 1950s in commercial settings, they are also essentially limited to uranium (U-235) fuel. This is where fast neutron reactors are highly attractive.

Fast neutron reactors can also fission other fissile elements, covering the full spectrum of neutron cross sections. TerraPower’s Natrium reactor is one such fast reactor, and it’s the world’s first fast reactor that not only targets commercial use, but also comes with its own grid-level storage in the form of a molten salt reservoir.

The upshot of this is that not only can these Natrium reactors use all of the spent LWR fuel in the US and elsewhere as their fuel, but they should also be highly efficient at load-following, traditionally a weak spot of thermal plants.

TerraPower and its partners are currently looking to build a demonstration plant in Wyoming, at the site of a retiring coal plant. This would be a 345 MWe (peak 500 MWe) reactor.

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The Trouble With Hubble: Payload Computer Glitch Stops Science At The Space Observatory

July 2, 2021 by Dan Maloney 21 Comments

The Hubble Space Telescope’s remarkably long service life and its string of astonishing contributions to astronomy belie its troubled history. Long before its launch into low Earth orbit in 1990, Hubble suffered from design conflicts, funding and budgetary pressures, and even the death of seven astronauts. Long delayed, much modified, and mistakenly sent aloft with suboptimal optics, Hubble still managed to deliver results that have literally changed our view of the universe, and is perhaps responsible for more screensaver and desktop pictures than any other single source.

But all of that changed on June 13 of this year, when Hubble suffered a computer glitch that interrupted the flow of science data from the orbiting observatory. It’s not yet clear how the current issue with Hubble is going to pan out, and what it all means for the future of this nearly irreplaceable scientific asset. We all hope for the best, of course, but while we wait to see what happens, it’s worth taking the opportunity to dive inside Hubble for a look at its engineering and what exactly has gone wrong up there.

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Could Airships Make A Comeback With New Hybrid Designs?

July 1, 2021 by Zoe Skyforest 101 Comments

Airships. Slow, difficult to land, and highly flammable when they’re full of hydrogen. These days, they’re considered more of a historical curiosity rather than a useful method of transport.

Hybrid Air Vehicles are a UK-based startup working to create a modern take on the airship concept. The goal is to create cleaner air transport for short-hop routes, while also solving many of the issues with the airship concept with a drastic redesign from the ground up. Their vehicle that will do all this goes by the name of Airlander 10. But is it enough to bring airships back to the skies?

A Hybrid Technology

Airlander 10 seen taking off during its first flight.

The Airlander 10 is not a lighter-than-air craft like traditional airships. Instead, the vehicle uses the buoyancy from its helium envelope to create only 60-80% of its lift. The rest of the left is generated aerodynamically by air passing over the eliptical shape of the airship’s body. This lift can also be further augmented by two diesel-powered ducted fans on the sides of the airship, which can pivot to assist with takeoff and landing. Two further fixed ducted fans on the rear provide the primary propulsion for the craft.

The hybrid approach brings several benefits over the traditional airship model. Chief among them is that as the Airlander 10 is heavier than air, it need not vent helium throughout flight to avoid becoming positively buoyant as fuel burns off, nor does it need to vent helium to land. However, it still maintains the capability to loiter for incredibly long periods in the sky as it needs to burn very little fuel to stay aloft. Reportedly, it is capable of five days when manned, and even longer durations if operated in an unmanned configuration. Using helium for lift instead of solely relying on engine thrust and wings means that it is much more fuel efficient than traditional fixed-wing airliners. The company’s own estimates suggest the Airlander 10 could slash emissions on short-haul air routes by up to 90%. The gentle take-off and landing characteristics also mean the vehicle doesn’t require traditional airport facilities, making it possible to operate more easily in remote areas, on grass, sand, or even water. Continue reading “Could Airships Make A Comeback With New Hybrid Designs?” →

Adding A Gentle Touch To Prosthetic Limbs With Somatosensory Stimulation

June 30, 2021 by Maya Posch 5 Comments

When Nathan Copeland suffered a car accident in 2004, damage to his spinal cord at the C5/C6 level resulted in tetraplegic paralysis. This left him initially at the age of 18 years old to consider a life without the use of his arms or legs, until he got selected in 2014 for a study at the University of Pittsburgh involving the controlling of a robotic limb using nothing but one’s mind and a BCI.

While this approach, as replicated in various other studies, works well enough for simple tasks, it comes with the major caveat that while it’s possible to control this robotic limb, there is no feedback from it. Normally when we try to for example grab an object with our hand, we are aware of the motion of our arm and hand, until the moment when our fingers touch the object which we’re reaching for.

In the case of these robotic limbs, the only form of feedback was of the visual type, where the user had to look at the arm and correct its action based on the observation of its position. Obviously this is far from ideal, which is why Nathan hadn’t just been implanted with Utah arrays that read out his motor cortex, but also arrays which connected to his somatosensory cortex.

As covered in a paper by Flesher et al. in Nature, by stimulating the somatosensory cortex, Nathan has over the past few years regained a large part of the sensation in his arm and hand back, even if they’re now a robotic limb. This raises the question of how complicated this approach is, and whether we can expect it to become a common feature of prosthetic limbs before long. Continue reading “Adding A Gentle Touch To Prosthetic Limbs With Somatosensory Stimulation” →