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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Where There Is No Down: Measuring Liquid Levels In Space

As you can probably imagine, we get tips on a lot of really interesting projects here at Hackaday. Most are pretty serious, at least insofar as they aim to solve a specific problem in some new and clever way. Some, though, are a little more lighthearted, such as a fun project that came across the tips line back in May. Charmingly dubbed “pISSStream,” the project taps into NASA’s official public telemetry stream for the International Space Station to display the current level of the urine tank on the Space Station.

Now, there are a couple of reactions to a project like this when it comes across your desk. First and foremost is bemusement that someone would spend time and effort on a project like this — not that we don’t appreciate it; the icons alone are worth the price of admission. Next is sheer amazement that NASA provides access to a parameter like this in its public API, with a close second being the temptation to look at what other cool endpoints they expose.

But for my part, the first thing I thought of when I saw that project was, “How do they even measure liquid levels in space?” In a place where up and down don’t really have any practical meaning, the engineering challenges of liquid measurement must be pretty interesting. That led me down the rabbit hole of low-gravity process engineering, a field that takes everything you know about how fluids behave and flushes it into the space toilet.

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One of the photo-detector spheres of ARCA (Credit: KM3NeT)

Confirmation Of Record 220 PeV Cosmic Neutrino Hit On Earth

Neutrinos are exceedingly common in the Universe, with billions of them zipping around us throughout the day from a variety of sources. Due to their extremely low mass and no electric charge they barely ever interact with other particles, making these so-called ‘ghost particles’ very hard to detect. That said, when they do interact the result is rather spectacular as they impart significant kinetic energy. The resulting flash of energy is used by neutrino detectors, with most neutrinos generally pegging out at around 10 petaelectronvolt (PeV), except for a 2023 event.

This neutrino event which occurred on February 13th back in 2023 was detected by the KM3NeT/ARCA detector and has now been classified as an ultra-high energy neutrino event at 220 PeV, suggesting that it was likely a cosmogenic neutrinos. When we originally reported on this KM3-230213A event, the data was still being analyzed based on a detected muon from the neutrino interaction even, with the researchers also having to exclude the possibility of it being a sensor glitch.

By comparing the KM3-230213A event data with data from other events at other detectors, it was possible to deduce that the most likely explanation was one of these ultra-high energy neutrinos. Since these are relatively rare compared to neutrinos that originate within or near Earth’s solar system, it’ll likely take a while for more of these detection events. As the KM3NeT/ARCA detector grid is still being expanded, we may see many more of them in Earth’s oceans. After all, if a neutrino hits a particle but there’s no sensor around to detect it, we’d never know it happened.


Top image: One of the photo-detector spheres of ARCA (Credit: KM3NeT)

How’s The Weather? (Satellite Edition)

When [Tom Nardi] reported on NOAA’s statement that many of its polar birds were no longer recommended for use, he mentioned that when the satellites do give up, there are other options if you want to pull up your own satellite weather imagery. [Jacopo] explains those other options in great detail.

For example, the Russian Meteor-M satellites are available with almost the same hardware and software stack, although [Jacopo] mentions you might need an extra filter since it is a little less tolerant of interference than the NOAA bird. On the plus side, Meteor-M is stronger than the NOAA satellite on 1.7 GHz, and you can even use a handheld antenna to pick it up. There are new, improved satellites of this series on their way, too.

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Remembering James Lovell: The Man Who Cheated Death In Space

Many people have looked Death in the eye sockets and survived to tell others about it, but few situations speak as much to the imagination as situations where there’s absolutely zero prospect of rescuers swooping in. Top among these is the harrowing tale of the Apollo 13 moon mission and its crew – commanded by James “Jim” Lovell – as they found themselves stranded in space far away from Earth in a crippled spacecraft, facing near-certain doom.

Lovell and his crew came away from that experience in one piece, with millions tuning into the live broadcast on April 17 of 1970 as the capsule managed to land safely back on Earth, defying all odds. Like so many NASA astronauts, Lovell was a test pilot. He graduated from the US Naval Academy in Maryland, serving in the US Navy as a mechanical engineer, flight instructor and more, before being selected as NASA astronaut.

On August 7, 2025, Lovell died at the age of 97 at his home in Illinois, after a dizzying career that saw a Moon walk swapped for an in-space rescue mission like never seen before.

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Australia’s Space Program Finally Gets Off The Pad, But Only Barely

Australia is known for great beaches, top-tier coffee, and a laidback approach to life that really doesn’t square with all the rules and regulations that exist Down Under. What it isn’t known for is being a spacefaring nation.

As it stands, a startup called Gilmour Space has been making great efforts to give Australia the orbital launch capability it’s never had. After numerous hurdles and delays, the company finally got their rocket off the launch pad. Unfortunately, it just didn’t get much farther than that.

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Annealing In Space: How NASA Saved JunoCam In Orbit Around Jupiter

The Juno spacecraft was launched towards Jupiter in August of 2011 as part of the New Frontiers series of spacecraft, on what would originally have been a 7-year mission, including a nearly 5 year cruise to the planet. After a mission extension, it’s currently orbiting Jupiter, allowing for many more years of scientific data to be gathered using its instruments. One of these instruments is the JunoCam (JCM), a visible light camera and telescope. Unfortunately the harsh radiation environment around Jupiter had led many to believe that this camera would fail before long. Now it seems that NASA engineers have successfully tested a fix.

Location of the Juno spacecraft's science instruments. (Credit: NASA)
Location of the Juno spacecraft’s science instruments.

Although the radiation damage to JCM was obvious a few dozen orbits in – and well past its original mission’s 34 orbits – the big question was exactly what was being damaged by the radiation, and whether something could be done to circumvent or fix it. The good news was that the image sensor itself was fine, but one of the voltage regulators in JCM’s power supply was having a bad time. This led the engineers to try annealing the affected part by cranking up one of the JCM’s heaters to a balmy 25°C, well above what it normally is kept at.

This desperate step seemed to work, with massively improved image quality on the following orbits, but soon the images began to degrade again. Before an approach to Jupiter’s moon Io, the engineers thus tried it again but this time cranked the JCM’s heater up to eleven and crossed their fingers. Surprisingly this fixed the issue over the course of a week, until the JCM seems as good as new. Now the engineers are trying their luck with Juno‘s other instruments as well, with it potentially providing a blueprint for extending the life of spacecraft in general.

Thanks to [Mark Stevens] for the tip.