Apollo Lunar Surface Experiments Package of the Apollo 16 mission (Credit: NASA)

ALSEP: Apollo’s Modular Lunar Experiments Laboratory

December 23, 2024 by Maya Posch 13 Comments

Down-Sun picture of the RTG with the Central Station in the background. (Credit: NASA)

Although the US’ Moon landings were mostly made famous by the fact that it featured real-life human beings bunny hopping across the lunar surface, they weren’t there just for a refreshing stroll over the lunar regolith in deep vacuum. Starting with an early experimental kit (EASEP) that was part of the Apollo 11 mission, the Apollo 12 through Apollo 17 were provided with the full ALSEP (Apollo Lunar Surface Experiments Package). It’s this latter which is the subject of a video by [Our Own Devices].

Despite the Apollo missions featuring only one actual scientist (Harrison Schmitt, geologist), these Bendix-manufactured ALSEPs were modular, portable laboratories for running experiments on the moon, with each experiment carefully prepared by scientists back on Earth. Powered by a SNAP-27 radioisotope generator (RTG), each ALSEP also featured the same Central Station command module and transceiver. Each Apollo mission starting with 12 carried a new set of experimental modules which the astronauts would set up once on the lunar surface, following the deployment procedure for that particular set of modules.

Although the connection with the ALSEPs was terminated after the funding for the Apollo project was ended by US Congress, their transceivers remained active until they ran out of power, but not before they provided years worth of scientific data on many aspects on the Moon, including its subsurface characteristics and exposure to charged particles from the Sun. These would provide most of our knowledge of our Moon until the recent string of lunar landings by robotic explorers.

Heading image: Apollo Lunar Surface Experiments Package of the Apollo 16 mission (Credit: NASA)

Continue reading “ALSEP: Apollo’s Modular Lunar Experiments Laboratory” →

Charles Duke during his interview with Jack Gordon. (Credit: Jack Gordon, YouTube)

Lunar Landing Lunacy: Charles Duke Confronted With Reality-Deniers

August 24, 2024 by Maya Posch 104 Comments

Lunar Module pilot Charles Duke saluting the US flag during Apollo 16. (Credit: NASA)

Imagine: you spent years training for a sojourn to the Moon, flew there on top of a Saturn V rocket as part of Apollo 16, to ultimately land on the lunar surface. You then spend the next few days on the surface, walking and skipping across the lunar regolith while setting up experiments and exploring per your mission assignments. Then, you pack everything up and blast off from the lunar surface to the orbiting command module before returning to Earth and a hero’s welcome. Then, decades later, you are told to your face that none of that ever happened. That’s the topic of a recent interview which [Jack Gordon] recently did with astronaut [Charles Duke].

None of these ‘arguments’ provided by the reality-denying crowd should be too shocking or feel new, as they range from the amount of fuel required to travel to the moon (solved by orbital mechanics) to the impossibility of lighting on the Moon (covered by everyone and their dog, including the Mythbusters in 2008).

Of course, these days, we have lunar orbiters (LRO and others) equipped with powerful cameras zoomed in on the lunar surface, which have photographed the Apollo landing sites with the experiments and footsteps still clearly visible. Like today’s crowd of spherical Earth deniers, skeptics will denounce anything that doesn’t fit their ill-conceived narrative as ‘faked’ for reasons that only exist in their fevered imaginations.

A common objection we’ve heard is that if we went to the moon back then, why haven’t we been back? The reason is obvious: politics. The STS (Shuttle) project sucked up all funding and the USSR collapsed. Only recently has there been a new kind of ‘space race’ in progress with nations like China. That doesn’t keep countless individuals from dreaming up lunar landing conspiracy theories to file away with their other truth nuggets, such as how microwaved and genetically engineered foods cause cancer, vaccines are another government conspiracy to control the population, and nuclear power plants can explode like nuclear bombs.

Perhaps the best takeaway is that even if we have not found intelligent life outside Earth yet, for at least a few years, intelligent life was the only kind on Earth’s Moon. We wish [Charles Duke] many happy returns, with maybe a casual return to the Moon in the near future as well, to frolic once more on the lunar surface.

Not that there hasn’t been a moon hoax, just not lately. If you want to watch the old Apollo video, it has been improved in recent years.

Continue reading “Lunar Landing Lunacy: Charles Duke Confronted With Reality-Deniers” →

Lunar Lander Game Asks You To Write A Simple Autopilot

August 16, 2024 by Donald Papp 28 Comments

Everyone likes a good lunar landing simulator, and [Dominic Doty] wrote a fun take on the idea: your goal is to write an autopilot controller to manage the landing. Try it out!

Virtual landers are far cheaper than real ones, thank goodness.

[Dominic] was inspired in part by this simple rocket landing game which is very much an exercise in reflex and intuition, not to mention being much faster-paced than the classic 1979 video game (which you can also play in your browser here.)

[Dominic]’s version has a similar classic look to the original, but embraces a more thoughtful approach. In it, one uses plain JavaScript to try to minimize the lander’s angle, velocity, and angular velocity in order to land safely on the generated terrain.

Want to see if you have the right stuff? Here’s a direct link to Lunar Pilot. Don’t get discouraged if you don’t succeed right away, though. Moon landings have had plenty of failures, and are actually very hard.

The Lunar Odyssey: Moon Landings From The 1960s To Today’s Attempts

March 20, 2024 by Maya Posch 21 Comments

With the recent string of lunar landing attempts, it’s interesting to consider how much things have changed – or stayed the same – since the first soft landing attempts in the 1960s with the US Ranger and USSR Luna landers. During the 1950s the possibility of landing a spacecraft on the Moon’s surface was investigated and attempted by both the US and USSR. This resulted in a number of lunar lander missions in the 1960s, with the US’s Ranger 3 and 5 missing the Moon, Ranger 4 nearly missing it but instead crashing into the far side of the Moon, and eventually the USSR’s Luna 9 making the first touchdown on the lunar surface in 1966 after a string of USSR mission failures.

What’s perhaps most interesting was how these first US and USSR spacecraft managed to touch down, with Luna 9 opting to inflate a landing airbag and bounce until it came to a halt. This approach had doomed Luna 8, as its airbag got punctured during inflating, causing a hard crash. Meanwhile the US’s Surveyor 1 was the first US spacecraft to land on the Moon, opting to use a solid-fuel retrorocket to slow the craft down and three liquid-fueled vernier thrusters to prepare it for a drop down from 3.4 meters onto the lunar surface.

Now, nearly 60 years later, the landers we sent regularly make it to the lunar surface, but more often than not end up crashing or toppling over into awkward positions. How much have lunar landings really changed?

Continue reading “The Lunar Odyssey: Moon Landings From The 1960s To Today’s Attempts” →

A Soyuz-2.1b rocket booster with a Fregat upper stage and the Luna 25 lunar lander blasts off from a launchpad at the Vostochny Cosmodrome in Amur Oblast, Russia.

Luna 25’s Demise: Raising Fundamental Questions About Russia’s Space Program

August 21, 2023 by Maya Posch 79 Comments

The recent news that Russia’s Luna 25 Moon lander had made an unexpected lithobraking detour into the Moon’s surface, rather than the expected soft touchdown was met by a variety of responses, ranging from dismay to outright glee, much of it on account of current geopolitical considerations. Yet politics aside, the failure of this mission casts another shadow on the prospects of Russia’s attempts to revive the Soviet space program after a string of failures, including its ill-fated Mars 96 and Fobos-Grunt Mars missions, the latter of which also destroyed China’s first Mars orbiter (Yinghuo-1) and ignited China’s independent Mars program.

To this day, only three nations have managed to land on the Moon in a controlled fashion: the US, China, and the Soviet Union. India may soon join this illustrious list if its Chandrayaan-3 mission’s Vikram lander dodges the many pitfalls of soft touchdowns on the Moon’s surface. While Roscosmos has already started internal investigation, it does cast significant doubt on the viability of the Russian Luna-Glob (‘Lunar Sphere’) lunar exploration program.

Will Russia manage to pick up where the Soviet Union left off in 1976 with the Luna 24 lunar sample return mission?

Continue reading “Luna 25’s Demise: Raising Fundamental Questions About Russia’s Space Program” →

Hackaday Links: May 14, 2023

May 14, 2023 by Dan Maloney 13 Comments

It’s been a while since we heard from Dmitry Rogozin, the always-entertaining former director of Roscosmos, the Russian space agency. Not content with sending mixed messages about the future of the ISS amid the ongoing war in Ukraine, or attempting to hack a mothballed German space telescope back into action, Rogozin is now spouting off that the Apollo moon landings never happened. His doubts about NASA’s seminal accomplishment apparently started while he was still head of Roscosmos when he tasked a group with looking into the Apollo landings. Rogozin’s conclusion from the data his team came back with isn’t especially creative; whereas some Apollo deniers go to great lengths to find “scientific proof” that we were never there, Rogozin just concluded that because NASA hasn’t ever repeated the feat, it must never have happened.

Continue reading “Hackaday Links: May 14, 2023” →

China's Chang'e-4 mission made the first-ever landing on the far side of the Moon in 2019. (Credit: Xinhua/Alamy)

Moon Mission Failures, Or Why Are Lunar Landings So Hard?

May 3, 2023 by Maya Posch 41 Comments

Given the number of spacecraft (both crewed and uncrewed) that touched down on the Moon during the Space Race it’s sometimes hard to imagine why today, with all our modern technology, our remotely operated vehicles seem to have so much trouble not smashing themselves to bits on the regolith surface.

This is the focus of a recent article in Nature that explores the aspects which still make soft landings on our closest space body so much harder than the tragic lithobraking as most recently demonstrated by ispace’s M1 lander.

So far only three entities have successfully landed a craft on the Moon’s surface: the government-funded space agencies of the US, USSR, and China. Of them, only China managed to do so on their first try in 2013 (Chang’e-3), and again in 2019 on the far side of the Moon (Chang’e-4). What is the toughest part about a Moon landing is not to get near the Moon, but it’s about getting close to the surface without getting lost. Since there are no navigation satellites beyond those you put up before the landing, and a lot of Moon dust that will be kicked up by any landing rocket engines, it can be tough to gauge one’s exact location and distance to the surface.

In the case of the ispace lander it would appear that it tragically ran out of propellant before it could safely touch down, which is another major concern. Both the US and USSR would smash Moon landers into its surface until the first successful landing in 1966, which makes the manned touchdown by Apollo 11 in 1969 even more impressive.