If you are a science fiction fan, you are probably aware of one of the genre’s oddest dichotomies. A lot of science fiction is concerned about if a robot, alien, or whatever is a person. However — sometimes in the same story — finding life is as easy as asking the science officer with a fancy tricorder. If you go to Mars and meet Marvin, it is pretty clear he’s alive, but faced with a bunch of organic molecules, the task is a bit harder. Now it is going to get harder still because Cornell scientists have created a material that has an artificial metabolism and checks quite a few boxes of what we associate with life. You can read the entire paper if you want more detail.
Three of the things people look for to classify something as alive is that it has a metabolism, self-arranges, and reproduces. There are other characteristics, depending on who you ask, but those three are pretty crucial.
We are very familiar with retrocomputers, and if you want you too can build a computer that could have been made in the late ’70s on a breadboard. Just grab your CPU of choice, add some RAM, some ROM, a ton of jumper wires, and give it some way to talk to the outside world. The problem with the computers inspired by yesteryear is that they all, inexplicably, use through-hole parts. If only someone used the small QFP parts instead of the big chonkin’ PDIPs, we could have really small retrocomputers. That’s exactly what [NotArtyom] did, and he managed to come up with a wearable 6502 watch.
The system design for this 6502-based watch is fairly standard for what you would find in any other retrocomputer. There’s a PLCC 6502, 32k of SRAM, 16k of ROM, and a PLLC’d 6522 for a bit of IO. There are a few peripherals hanging off the 6522, and since this thing is a watch the most important is a real time clock. There’s also a Nokia LCD and a 20-pin Commodore keyboard connector.
Software-wise, most of the ROM is dedicated to G’Mon, a generic monitor that can view and modify memory. There’s also EhBasic, and a kernel to handle the RTC, keyboard, and display.
Whether or not this is a useful smartwatch isn’t the question; this is one of the first retrocomputer projects we’ve seen that lean into the non-PDIP versions of these classic chips. This is a bit surprising, because you can still buy these parts, PDIP or not, new from the usual vendors. If nothing else, it’s a demonstration of what can be done with modern IC packages.
If you want to talk about antennas, the amateur radio community has you covered, with one glaring exception. Very low frequency and Extremely Low Frequency radio isn’t practiced very much, ultimately because it’s impractical and you simply can’t transmit much information when your carrier frequency is measured in tens of Hertz. There is more information on Extremely Low Frequency radio in Michael Crichton’s Sphere than there is in the normal parts of the Internet. Now there might be an easier way to play with VLF radiation, thanks to developers at the National Accelerator Laboratory. They’ve developed a piezoelectric transmitter for very long wavelengths.
Instead of pushing pixies through an antenna, this antenna uses a rod-shaped crystal of lithium niobate, a piezoelectric material. An AC voltage is applied to the rod makes it vibrate, and this triggers an oscillating electric current flow that’s emitted as VLF radiation. The key is that it’s these soundwaves bouncing around that define the resonant frequency, and the speed of sound in lithium niobate is a lot slower than the speed of light, but they’re translated into electric signals because of its piezoelectricity. For contrast, if this were a wire quarter-wave antenna it would be tens of kilometers long.
The application for this sort of antenna is ideally for where regular radio doesn’t work. Radio doesn’t work underwater, but nuclear subs trail an antenna out of the back to receive messages using Extremely Low Frequency radio. A walkie talkie doesn’t work in a mine, and this could potentially be used there. There is a patent for this piezoelectric antenna, so if anyone knows of a source of lithium niobate, put a link in the comments.
We’ve seen this trick before to make small antennas even smaller, but this is the first time we’ve seen it used in the VLF band, where it’s arguably even more impressive.
If the great Samuel Clemens were alive today, he might modify the famous meteorological quip often attributed to him to read, “Everyone complains about weather forecasts, but I can’t for the life of me see why!” In his day, weather forecasting was as much guesswork as anything else, reading the clouds and the winds to see what was likely to happen in the next few hours, and being wrong as often as right. Telegraphy and better instrumentation made forecasting more scientific and improved accuracy steadily over the decades, to the point where we now enjoy 10-day forecasts that are at least good for planning purposes and three-day outlooks that are right about 90% of the time.
What made this increase in accuracy possible is supercomputers running sophisticated weather modeling software. But models are only as good as the raw data that they use as input, and increasingly that data comes from on high. A constellation of satellites with extremely sensitive sensors watches the planet, detecting changes in winds and water vapor in near real-time. But if the people tasked with running these systems are to be believed, the quality of that data faces a mortal threat from an unlikely foe: the rollout of 5G cellular networks.
Whether it comes to rescuing people from a cave system or the underground maze of sewers, tunnels and the like that exist underneath any major city, having accurate maps of the area is always crucial to know what the optimal routes are, and what the expected dangers are. The same is true for combat situations, where such maps can mean the difference between the failure or success of a mission. This is why DARPA last year started the Subterranean Challenge, or ‘SubT’ for short.
This challenge seeks new approaches to map, navigate, and search underground environments during time-sensitive combat operations or disaster response scenarios, which would allow for these maps to be created on-demand, in the shortest amount of time possible. Multidisciplinary teams from the world are invited to create autonomous systems that can map such subsurface networks no matter the circumstances.
Some bittersweet news today as we get word that Israel’s Beresheet spacecraft unfortunately crashed shortly before touchdown on the Moon. According to telemetry received from the spacecraft right up until the final moments, the main engine failed to start during a critical braking burn which would have slowed the craft to the intended landing velocity. Despite attempts to restart the engine before impact with the surface, the craft hit the Moon too hard and is presumably destroyed. It’s likely that high resolution images from the Lunar Reconnaissance Orbiter will eventually be able to give us a better idea of the craft’s condition on the surface, but at this point the mission is now officially concluded.
The Beresheet Lander
It’s easy to see this as a failure. Originally conceived as an entry into the Google Lunar X Prize, the intended goal for the $100 million mission was to become the first privately funded spacecraft to not only touch down on the lunar surface, but navigate laterally through a series of powered “hops”. While the mission certainly fell short of those lofty goals, it’s important to remember that Beresheet did land on the Moon.
It didn’t make the intended soft landing, a feat accomplished thus far only by the United States, Russia, and China; but the fact of the matter is that a spacecraft from Israel is now resting on the lunar surface. Even though Beresheet didn’t survive the attempt, history must recognize Israel as the fourth country to put a lander on the surface of our nearest celestial neighbor.
It’s also very likely this won’t be the last time Israel reaches for the Moon. During the live broadcast of the mission, after it was clear Beresheet had been lost, Prime Minister Benjamin Netanyahu vowed his country would try again within the next two years. The lessons learned today will undoubtedly help refine their next mission, and with no competition from other nations in the foreseeable future, there’s still an excellent chance Israel will be able to secure their place in history as the fourth country to make a successful soft landing.
Beresheet’s view during descent
Of course you’ve got to get to the Moon before you can land on it, and in this respect, Beresheet was an unmitigated success. We previously covered the complex maneuvers required to put the craft into lunar orbit after riding to space as a secondary payload on the Falcon 9 rocket; a technique which we’ll likely see more of thanks to the NASA’s recent commitment to return to the Moon. Even if Beresheet never attempted to land on the surface, the fact that it was able to enter into a stable lunar orbit and deliver dramatic up-close images of the Moon’s surface will be a well deserved point of pride for Israel.
This won’t be the last time that hundreds of millions of dollars worth of high-tech equipment will be lost while pushing the absolute edge of the envelope, and that’s nothing to be upset over. Humans have an insatiable need to see what’s over the horizon and that means we must take on a certain level of risk. The alternative is stagnation, and in the long run that will cost us a lot more than a few crashed probes.
When it comes to mathematics, the average person can probably get through most of life well enough with just basic algebra. Some simple statistical concepts would be helpful, and a little calculus couldn’t hurt. But that leaves out a lot of interesting mathematical concepts that really do have applications in everyday life and are just plain fascinating in their own right.
Chief among these concepts is the Fourier transform, which is the key to understanding everything from how JPEGs work to how we can stream audio and video over the Internet. To help get your mind around the concept, [Jez Swanson] has this interactive Fourier transform visualizer that really drives home the important points. This is high-level stuff; it just covers the basic concepts of a Fourier transform, how they work, and what they’re good for in everyday life. There are no equations, just engaging animations that show how any function can be decomposed into a set of sine waves. One shows the approximation of a square wave with a slider to control to vary the number of component sine waves; a button lets you hear the resulting sound getting harsher as it approaches a true square wave. There’s also a great bit on epicycles and SVGs, and one of the best introductions to encoding images as JPEGs that we’ve seen. The best part: all the code behind the demos is available on GitHub.
