NASA Seeks Volunteers To Track Artemis II Mission

As NASA’s Artemis program trundles onwards at the blazing pace of a disused and very rusty crawler-transporter, the next mission on the list is gradually coming into focus. This will be the first crewed mission — a flyby of the Moon following in the footsteps of 1968’s Apollo 8 mission. As part of this effort, NASA is looking for volunteers who will passively track the Orion capsule and its crew of four as it makes its way around the Moon during its 10-day mission before returning to Earth. Details can be found here.

This follows on a similar initiative during the Artemis I mission, when participants passively tracked the radio signals from the capsule. For this upcoming mission NASA is looking for Doppler shift measurements on the Orion S-band (2200-2290 MHz) return link carrier signals, with the objective being to achieve and maintain a carrier lock.

Currently penciled in for a highly tentative April 2026, the Artemis II mission would fly on the same SLS Block 1 rocket configuration that launched the first mission, targeting a multi-trans-lunar injection (MTLI) profile to get to the Moon using a free return trajectory. The crew will check out the new life support system prior to starting the MTLI burns.

Because Artemis II will be on a free return trajectory it will not be orbiting the Moon, unlike Apollo 8’s crew who made ten lunar orbits. Incidentally, Apollo 8’s crew included James Lovell, who’d go on to fly the world-famous Apollo 13 mission. Hopefully the Artemis astronauts will be spared that level of in-space excitement.

NASA Is Taking Suggestions For Raising Swift’s Orbit

Launched in 2004, the Neil Gehrels Swift Observatory – formerly the Swift Gamma-Ray Burst Explorer – has been dutifully studying gamma-ray bursts (GRBs) during its two-year mission, before moving on to a more general space observation role during its ongoing mission. Unfortunately, the observatory is in LEO, at an altitude of around 370 km. The natural orbital decay combined with increased solar activity now threatens to end Swift’s mission, unless NASA can find someone who can boost its orbit.

Using Swift as a testbed for commercial orbit-boosting technologies, NASA is working with a number of companies to investigate options. One of these is the SSPICY demonstration of in-orbit inspection technology by Starfish Space that’s part of an existing Phase III program.

Although currently no option has been selected and Swift is still at risk of re-entering Earth’s atmosphere within the near future, there seems to be at least a glimmer of hope that this process can be reverted, and a perfectly fine triple-telescope space observatory can keep doing science for many years to come. Along the way it may also provide a blueprint for how to do the same with other LEO assets that are at risk of meeting a fiery demise.

Does It Make Sense To Upgrade A Prusa MK4S To A Core One?

One of the interesting things about Prusa’s FDM 3D printers is the availability of official upgrade kits, which allow you to combine bits off an older machine with those of the target machine to ideally save some money and not have an old machine gathering dust after the upgrade. While for a bedslinger-to-bedslinger upgrade this can make a lot of sense, the bedslinger to CoreXY Core One upgrade path is a bit more drastic. Recently the [Aurora Tech] channel had a look at which upgrade path makes the most sense, and in which scenario.

A big part of the comparison is the time and money spent compared to the print result, as you have effectively four options. Either you stick with the MK4S, get the DIY Core One (~8 hours of assembly time), get the pre-assembled Core One (more $$), or get the upgrade kit (also ~8 hours). There’s also the fifth option of getting the enclosure for the MK4S, but it costs about as much as the upgrade kit, so that doesn’t make a lot of logical sense.

In terms of print quality, it’s undeniable that the CoreXY motion system provides better results, with less ringing and better quality with tall prints, but unless you’re printing more than basic PLA and PETG, or care a lot about the faster print speeds of the CoreXY machine with large prints, the fully enclosed Core One is a bit overkill and sticking with the bedslinger may be the better choice.

The long and short of it is that you have look at each option and consider what works best for your needs and your wallet.

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The Confusing World Of Wood Preservation Treatments

Wood is an amazing material to use around the house, both for its green credentials and the way it looks and feels. That said, as a natural product there are a lot of microorganisms and insects around that would love to take a few good nibbles out of said wood, no matter whether it’s used for fencing, garden furniture or something else. For fencing in particular wood treatments are therefore applied that seek to deter or actively inhibit these organisms, but as the UK bloke over at the [Rag ‘n’ Bone Brown] YouTube channel found out last year, merely slapping on a coating of wood preserver may actually make things worse.

For the experiment three tests were set up, each with an untreated, self-treated and two pressure treated (tanalized) sections. Of the pressure treated wood one had a fresh cut on the exposed side, with each of the three tests focusing on a different scenario.

After three years of these wood cuts having been exposed to being either partially buried in soil, laid on the long side or tossed in a bucket, all while soaking up the splendid wonders of British weather, the results were rather surprising and somewhat confusing. The self-treated wood actually fared worse than the untreated wood, while the pressure treated wood did much better, but as a comment by [davidwx9285] on the video notes, there are many questions regarding how well the pressure treatment is performed.

While the self-treatment gets you generally only a surface coating of the – usually copper-based – compound, the vacuum pressure treatment’s effectiveness depends on how deep the preservative has penetrated, which renders some treated wood unsuitable for being buried in the ground. Along with these factors the video correctly identifies the issue of grain density, which is why hardwoods resist decay much better than e.g. pine. Ultimately it’s quite clear that ‘simply put on a wood preserver’ isn’t quite the magical bullet that it may have seemed to some.

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Illustration of a Gemini B reentry vehicle separating from the Manned Orbiting Laboratory (MOL). (Source: US Air Force)

The Advanced Project Gemini Concepts That Could Have Been

Looking back on the trajectory leading to Project Apollo and the resulting Moon missions, one can be forgiven for thinking that this was a strict and well-defined plan that was being executed, especially considering the absolute time crunch. The reality is that much of this trajectory was in flux, with the earlier Project Gemini seeing developments towards supplying manned space stations and even its own Moon missions. [Spaceflight Histories] recently examined some of these Advanced Gemini concepts that never came to pass.

In retrospect, some of these seem like an obvious evolution of the program. Given both NASA and the US Air Force’s interest in space stations at the time, the fact that a up-sized “Big Gemini” was proposed as a resupply craft makes sense. Not to be confused with the Gemini B, which was a version of the spacecraft that featured an attached laboratory module. Other concepts, like the paraglider landing feature, were found to be too complex and failure prone.

The circumlunar, lunar landing and Apollo rescue concepts were decidedly more ambitious and included a range of alternatives to the Project Apollo missions, which were anything but certain especially after the Apollo 1 disaster. Although little of Advanced Gemini made it even into a prototype stage, it’s still a fascinating glimpse at an alternate reality.

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Why Super Mario 64 Wastes So Much Memory

The Nintendo 64 was an amazing video game console, and alongside consoles like the Sony PlayStation, helped herald in the era of 3D games. That said, it was new hardware, with new development tools, and thus creating those early N64 games was a daunting task. In an in-depth review of Super Mario 64’s code, [Kaze Emanuar] goes over the curious and wasteful memory usage, mostly due to unused memory map sections, unoptimized math look-up tables, and greedy asset loading.

The game as delivered in the Japanese and North-American markets also seems to have been a debug build, with unneeded code everywhere. That said, within the context of the three-year development cycle, it’s not bad at all — with twenty months spent by seven programmers on actual development for a system whose hardware and tooling were still being finalized, with few examples available of how to do aspects like level management, a virtual camera, etc. Over the years [Kaze] has probably spent more time combing over SM64‘s code than the original developers, as evidenced by his other videos.

As noted in the video, later N64 games like Legend of Zelda: Ocarina of Time are massively more optimized and streamlined, as lessons were learned and tooling improved. For the SM64 developers, however, they had a gargantuan 4 MB of fast RDRAM to work with, so optimization and memory management likely got kicked down to the bottom on the priority list. Considering the absolute smash hit that SM64 became, it seems that these priorities were indeed correct.

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Tefifon: Germany’s Tape-Shaped Record Format

A Tefifon cartridge installed for playback. (Credit: Our Own Devices, YouTube)
A Tefifon cartridge installed for playback. (Credit: Our Own Devices, YouTube)

Recently the [Our Own Devices] YouTube channel took a gander at the Tefifon audio format. This was an audio format that competed with shellac and vinyl records from the 1930s to the 1960s, when the company behind it went under. Some people may already know Tefifon as [Matt] from Techmoan has covered it multiple times, starting with a similar machine about ten years ago, all the way up to the Stereo Tefifon machine, which was the last gasp for the format.

There’s a lot to be said for the Tefifon concept, as it fixes many of the issues of shellac and vinyl records, including the limited run length and having the fragile grooves exposed to damage and dust. By having the grooves instead on a flexible band that got spooled inside a cartridge, they were protected, with up to four hours of music or eight hours of spoken content, i.e. audio books.

Although the plastic material used for Tefifon bands suffered from many of the same issues as the similar Dictabelt audio recording system, such as relatively rapid wear and degradation (stiffening) of the plastic, it was mostly the lack of interest from the audio labels that killed the format. With the big labels and thus big artists heavily invested in records, the Tefifon never really got any hits and saw little use outside of West Germany throughout the 1950s and 1960s before its last factories were shuttered.

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