It may be blurry and blotchy, but it’s ours. The first images of the supermassive black hole at the center of the Milky Way galaxy were revealed this week, and they caused quite a stir. You may recall the first images of the supermassive black hole at the center of the M87 galaxy from a couple of years ago: spectacular images that captured exactly what all the theories said a black hole should look like, or more precisely, what the accretion disk and event horizon should look like, since black holes themselves aren’t much to look at. That black hole, dubbed M87*, is over 55 million light-years away, but is so huge and so active that it was relatively easy to image. The black hole at the center of our own galaxy, Sagittarius A*, is comparatively tiny — its event horizon would fit inside the orbit of Mercury — a much closer at only 26,000 light-years or so. But, our black hole is much less active and obscured by dust, so imaging it was far more difficult. It’s a stunning technical achievement, and the images are certainly worth checking out.
Another one from the “Why didn’t I think of that?” files — contactless haptic feedback using the mouth is now a thing. This comes from the Future Interfaces Group at Carnegie-Mellon and is intended to provide an alternative to what ends up being about the only practical haptic device for VR and AR applications — vibrations from off-balance motors. Instead, this uses an array of ultrasonic transducers positioned on a VR visor and directed at the user’s mouth. By properly driving the array, pressure waves can be directed at the lips, teeth, and tongue of the wearer, providing feedback for in-world events. The mock game demonstrated in the video below is a little creepy — not sure how many people enjoyed the feeling of cobwebs brushing against the face or the splatter of spider guts in the mouth. Still, it’s a pretty cool idea, and we’d like to see how far it can go.
If you were asked to name the coldest spot in the solar system, chances are pretty good you’d think it would be somewhere as far as possible from the ultimate source of all the system’s energy — the Sun. It stands to reason that the further away you get from something hot, the more the heat spreads out. And so Pluto, planet or not, might be a good guess for the record low temperature.
But, for as cold as Pluto gets — down to 40 Kelvin — there’s a place that much, much colder than that, and paradoxically, much closer to home. In fact, it’s only about a million miles away, and right now, sitting at a mere 6 Kelvin, the chunk of silicon at the focal plane of one of the main instruments aboard the James Webb Space telescope makes the surface of Pluto look downright balmy.
The depth of cold on Webb is all the more amazing given that mere meters away, the temperature is a sizzling 324 K (123 F, 51 C). The hows and whys of Webb’s cooling systems are chock full of interesting engineering tidbits and worth an in-depth look as the world’s newest space telescope gears up for observations.
Keeping tabs on the night sky is an enjoyable way to stay connected to the stars, and astronomy can be accessible to most people with a low entry point for DIY telescopes. For those who live in areas with too much light pollution, though, cost is not the only issue facing amateur astronomers. Luckily there are more ways to observe the night sky, like with this open source software package from [elanorlutz] which keeps tabs on all known asteroids.
The software is largely based on Python and uses a number of databases from NASA to allow anyone with a computer to explore various maps of the solar system and the planetary and non-planetary bodies within it. Various trajectories can be calculated, and paths of other solar system bodies can be shown with respect to an observer in various locations. Once the calculations are made in Python it is able to export the images for use in whichever image manipulation software you prefer.
When Tonga’s Hunga-Tonga Hunga-Ha’apai volcano erupted on January 15, one hacker in the UK knew just what to do. Sandy Macdonald from York quickly cobbled together a Raspberry Pi and a pressure/humidity sensor board and added a little code to create a recording barometer. The idea was to see if the shock wave from the eruption would be detectable over 16,000 km away — and surprise, surprise, it was! It took more than 14 hours to reach Sandy’s impromptu recording station, but the data clearly show a rapid pulse of increasing pressure as the shockwave approached, and a decreased pressure as it passed. What’s more, the shock wave that traveled the “other way” around the planet was detectable too, about seven hours after the first event. In fact, data gathered through the 19th clearly show three full passes of the shockwaves. We just find this fascinating, and applaud Sandy for the presence of mind to throw this together when news of the eruption came out.
Good news for professional astronomers and others with eyes turned skyward — it seems like the ever-expanding Starlink satellite constellation isn’t going to kill ground-based observation. At least that’s the conclusion of a team using the Zwicky Transient Facility (ZTF) at the Palomar Observatory outside San Diego. ZTF is designed to catalog anything that blinks, flashes, or explodes in the night sky, making it perfect to detect the streaks from the 1,800-odd Starlink satellites currently in orbit. They analyzed the number of satellite transients captured in ZTF images, and found that fully 20 percent of images show streaks now, as opposed to 0.5 percent back in 2019 when the constellation was much smaller. They conclude that at the 10,000 satellite full build-out, essentially every ZTF image will have a streak in it, but since the artifacts are tiny and well-characterized, they really won’t hinder the science to any appreciable degree.
Speaking of space, we finally have a bit of insight into the causes of space anemia. The 10% to 12% decrease in red blood cells in astronauts during their first ten days in space has been well known since the dawn of the Space Age, but the causes had never really been clear. It was assumed that the anemia was a result of the shifting of fluids in microgravity, but nobody really knew for sure until doing a six-month study on fourteen ISS astronauts. They used exhaled carbon monoxide as a proxy for the destruction of red blood cells (RBCs) — one molecule of CO is liberated for each hemoglobin molecule that’s destroyed — and found that the destruction of RBCs is a primary effect of being in space. Luckily, there appears to be a limit to how many RBCs are lost in space, so the astronauts didn’t suffer from complications of severe anemia while in space. Once they came back to gravity, the anemia reversed, albeit slowly and with up to a year of measurable changes to their blood.
And finally, if you’re in the mood for a contest, why not check out WIZNet’s Ethernet HAT contest? The idea is to explore what a Raspberry Pi Pico with Ethernet attached is good for. WIZNet has two flavors of board: one is an Ethernet HAT for the Pico, while the other is as RP2040 with built-in Ethernet. The good news is, if you submit an idea, they’ll send you a board for free. We love it when someone from the Hackaday community wins a contest, so if you enter, be sure to let us know. And hurry — submissions close January 31.
Starting projects is easy. It’s the finishing part that many of us have trouble with. We can hardly imagine completing a project after more than a decade, but seeing the breathtaking results of [J-P Metsavainio]’s gigapixel composite image of our galaxy might just make us reconsider. The photograph, which we highly suggest you go check out in its full glory, has been in progress since 2009, features 1250 total hours of exposure time, and spans across 125 degrees of sky. It is simply spectacular.
Of course, it wasn’t an absolutely continuous effort to make this one image over those twelve years. Part of the reason for the extended time span is many frames of the mosaic were shot, processed, and released as their own individual pieces; each of the many astronomical features impressive in its own right. But, over the years, he’s filled in the gaps between and has been able to release a more and more complete picture of our galactic home.
A project this long, somewhat predictably, eventually outlives the technology used to create it. Up until 2014, [Metsavainio]’s setup included a Meade 12-inch telescope and some modified Canon optics. Since then, he’s used a dedicated equatorial mount, astrocamera, and a Tokina lens (again, modified) with an 11-inch Celestron for longer focal lengths. He processes the frames in Photoshop, accounting for small exposure and color differences and aligning the images based on background stars. He’s had plenty of time to get his process down, though, so the necessary tweaking is relatively minor.
Some of the most expensive hobbies have some of the more ingenious hacks on display, generally to lower the cost of entry to various parts the hobby itself. Amateur astronomy has expensive, necessary equipment such as telescopes and other optics, but also has a large group of people willing to build their own gear out of some surprising materials rather than buy pre-built equipment.
One of the latest telescopes from [The Amateur Engineer] uses several bowls from IKEA to build the mirror mount. It’s a variation of a Portaball telescope, which is similar to a Dobsonian telescope except that it is much easier to adjust and point in any direction. This “Portabowl” telescope uses two bowls epoxied together and weighted at the bottom as the core of the build. The mirror mounts inside the ball, and some supports are attached to it to hold the eyepiece and mount. With some paint and some minor adjustments it’s ready to go stargazing.
There are a few improvements to this build planned for the future, such as the creation of a larger ball that will make operating the scope easier. All in all, though, it’s an excellent example of amateur astronomy even without needing to go as far as grinding one’s own mirrors.
Well, that was quite a show! The Perseverance rover arrived on Mars Thursday. Don’t tell the boss, but we spent the afternoon watching the coverage in the house on the big TV rather than slaving away in the office. It was worth it; for someone who grew up watching Jules Bergman and Frank Reynolds cover the Apollo program and the sometimes cheesy animations provided by NASA, the current coverage is pretty intense. A replay of the coverage is available – skip to about the 1:15:00 mark to avoid all the filler and fluff preceding the “Seven Minutes of Terror” main event. And not only did they safely deliver the package, but they absolutely nailed the landing. Perseverance is only about 2 km away from the ancient river delta it was sent to explore for signs of life. Nice shooting!
We’re also being treated to early images from Jezero crater. The first lowish-rez shots, from the fore and after hazard cameras, popped up just a few seconds after landing — the dust hadn’t even settled yet! Some wags complained about the image quality, apparently without thinking that the really good camera gear was stowed away and a couple of quick check images with engineering cameras would be a good idea while the rover still had contact with the Mars Reconnaissance Orbiter. Speaking of which, the HiRISE camera on the MRO managed to catch a stunning view of Perseverance’s descent under its parachute; the taking of that photo is an engineering feat all by itself. But all of this pales in comparison to a shot from one of the down-looking cameras in the descent stage, show Perseverance dangling from the skycrane just before touchdown. It was a really good day for engineering.
Would that our Earthly supply chains were as well-engineered as our Martian delivery systems. We’ve been hearing of issues all along the electronics supply chain, impacting a wide range of industries. Some of the problems are related to COVID-19, which has sickened workers staffing production and shipping lines. Some, though, like a fire at the AKM semiconductor plant in Japan, have introduced another pinch point in an already strained system. The fire was in October, but the impact on the manufacturer depending on the plant’s large-scale integration (LSI) and temperature-compensated crystal oscillators (TCXO) products is only just now being felt in the amateur radio market. The impact is likely not limited to that market, though — TCXOs pop up lots of gear, and the AKM plant made LSI chips for all kinds of applications.
What do you get when you combine a 3D-printer, a laser cutter, a CNC router, and a pick-and-place robot? Drones that fly right off the build plate, apparently. Aptly enough, it’s called LaserFactory, and it comes from MITs Computer Science and Artificial Intelligence Lab. By making different “bolt-on” tools for a laser cutter, the CSAIL team has combined multiple next-generation manufacturing methods in one platform. The video below shows a drone frame being laser-cut from acrylic, to which conductive silver paste is added by an extruder. A pick-and-place head puts components on the silver goo, solders everything together with a laser, and away it goes. They also show off ways of building up 3D structures, both by stacking up flat pieces of acrylic and by cutting and bending acrylic in situ. It’s obviously still just a proof of concept, but we really like the ideas presented here.
And finally, as proof that astronomers can both admit when they’re wrong and have fun while doing so, the most remote object in the Solar System has finally received a name. The object, a 400-km diameter object in a highly elliptical orbit that takes it from inside the orbit of Neptune to as far as 175 astronomical units (AU) from the Sun, is officially known as 2018 AG37. Having whimsically dubbed the previous furthest-known object “Farout,” astronomers kept with the theme and named its wayward sister “Farfarout.” Given the rapid gains in technology, chances are good that Farfarout won’t stay the Sun’s remotest outpost for long, and we fear the (Far)nout trend will eventually collapse under its own weight. We therefore modestly propose a more sensible naming scheme, perhaps something along the lines of “Farthest McFaraway.” It may not scale well, but at least it’s stupid.
