Astronaut Tracy Caldwell in the International Space Station. (Credit: NASA)

Making The Case For All-Female Exploration Missions To Mars And Beyond

May 16, 2023 by Maya Posch 118 Comments

A recent study in Nature Scientific Reports by Jonathan P. R. Scott and colleagues makes the case for sending exclusively all-female crews on long-duration missions. The reasoning here is simple: women have significant less body mass, with in the US the 50th percentile for women being 59.2 kg and 81.8 kg for men. This directly translates into a low total energy expenditure (TEE), along with a lower need for everything from food to water to oxygen. On a long-duration mission, this could conceivably save a lot of resources, thus increasing the likelihood of success.

With this in mind, it does raise the question of why female astronauts aren’t more commonly seen throughout Western space history, with Sally Ride being the first US astronaut to fly in 1983. This happened decades after the first female Soviet cosmonaut, when Valentina Tereshkova made history in 1963 on Vostok 6, followed by Svetlana Savitskaya in 1982 and again in 1984, when she became the first woman to perform a spacewalk.

With women becoming an increasingly more common sight in space, it does bear looking at what blocked Western women for so long, despite efforts to change this. It all starts with the unofficial parallel female astronaut selection program of the 1950s.

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DIY Programmable Guitar Pedal Rocks The Studio & Stage

May 16, 2023 by Donald Papp 10 Comments

Ever wondered how to approach making your own digital guitar effects pedal? [Steven Hazel] and a friend have done exactly that, using an Adafruit Feather M4 Express board and a Teensy Audio Adapter board together to create a DIY programmable digital unit that looks ready to drop into an enclosure and get put right to work in the studio or on the stage.

The bulk of the work is done with two parts, and can be prototyped easily on a breadboard.

[Steven] also made a custom PCB to mount everything, including all the right connectors, but the device can be up and running with not much more than the two main parts and a breadboard.

On the inside, the Adafruit Feather M4 Express board works with the audio board over I2S, a standard for sending serial digital audio between chips. Working with the audio itself is done with the Teensy Audio Library, providing a fantastic array of easy-to-use functions for processing and manipulating digital audio streams.

Together, all the right pieces are in place and [Steven] provides the code for a simple tremolo effect as a glimpse of what’s possible with the unit. Interested in going a bit further? [Steven] shares additional details about what’s involved in writing a custom effect from scratch using the Teensy Audio Library.

As mentioned, I2S is where it’s at when it comes to working with digital audio at the chip level, and our own Jenny List can tell you everything you need to know about I2S, a useful protocol that has actually been around since 1982!

The MOS CIA Lives On, In 74HCT

May 16, 2023 by Jenny List 12 Comments

It’s always pleasing to see a project we covered in its early stages reach maturity, so were very happy to bring you an update on [Daniel Molina]’s 74HCT6526. It’s a long-running effort to produce in 74 logic a faithful replica of the MOS Technologies CIA, the integrated I/O and timer chip found in so many of the 1980s Commodore machines. When we first covered it there was only one PCB, now the project has grown to a stack of three, with the remaining functions intended to fit on two more boards.

It was very common at the time for chips such as the CIA to integrate a set of common 8-bit peripherals onto one piece of silicon, both in general purpose with almost all functions of the original now implemented. hips and in more manufacturer specific parts such as this one. A project like this one is valuable because it provides a dive into the now less-common world of interfacing directly to a microprocessor data and address line. It’s unlikely that many Commodore 64s will end up with this stack of boards inside them, but it’s not impossible the design may help a few old machines when put on an FPGA.

Meanwhile, remember it’s not the only custom 1980s home computer chip replaced with 74 logic.