Wooden satellite heads to space in Mars exploration test
news.sky.com
news.sky.com
I found a (Japanese-language-only) news piece that shows some of the crafting and assembly of the satellite, and the box body certainly holds together by itself, via some beautifully intricate joinery:
10cm cube has a volume of 1 liter (10^3 ml). That's very wee.
<< LignoSat is made of honoki, a kind of magnolia tree native to Japan, and has been made using a traditional Japanese technique without screws or glue. >>
From photos I've seen while searching for more information, it does appear that there's a wooden core structure that is joined without fasteners. But it's then given a metal exoskeleton and what certainly appears to be metal fasteners.
I'd like to understand whether the goal is to create satellites without metal, as the article seemed to imply.
That's an optimistic view, I suspect it's just done to get people talking about it and to contrast the traditional joinery against the technology. There isn't likely to be any criteria by which wood is the best material to use for something like this.
Wooden spaceships, helmets, and other contraptions, augmented with metals and… other “spoiler” materials.
To anyone interested in space with a day or two to spare, I highly recommend playing Outer Wilds. It’s very good and unlike any other game (and I can’t explain why without spoiling the magic).
The reason aliens are likely to be made out of DNA and have cells is simply that those things tend to naturally come to exist in our universe. We don't really have any evidence that any other chemistry (e.g. silicon-based) can produce life in this universe. If DNA-based life comes about elsewhere in the universe, it won't look exactly like us, but that life is also likely to have both plants and animals, just because life tends to try to fill every available evolutionary niche.
I think you are confusing carbon-based life with DNA-based life, for which N=1, the Earth. There is absolutely no evidence that DNA exists anywhere else. I'm prepared to accept the argument that carbon+water is a good basis for life, but this does not inevitably lead to DNA-based replicators.
I'd even go as far as to say that DNA arose out of the fact that carbon based chemistry is good for life (we see N=1 case at least), and once we accept carbon based chemistry, amino-acids are the next optimal step, followed by something like the DNA to program the construction of proteins for amino acids.
Again, I'm just a layman so it'd be nice to know the views of experts in this area.
Imagine yourself existing on a microscopic scale, with your current consciousness intact. You'd look into the 'sky' and see an organelle membrane or nuclear envelope... what would your concept of the "program of life" be, while existing adjacent to DNA itself? Would this activity look a bit like some of the natural processes we witness and take part in on Earth?
Well yes, for sure, a replicator needs some sort of 'program', and if you go for carbon+water, amino acids are a good bet.
> and this is what DNA is
Yes, on Earth. But the actual horrendously weird and complex molecule Deoxyribonucleic acid is not the only way of implementing such a program. Check out a text such as 'How Life Works: A User’s Guide to the New Biology', by Philip Ball to see why I'm being picky here.
And as far as intelligent (technological intelligence) biological life it’s more likely than not to be far more similar to us than completely alien.
It would have to develop on land or at least be able to transition to land at some point. Can’t have complex chemistry under water, can’t have fire can’t have metallurgy.
Vision in a spectrum similar to us or higher is pretty much a must, both as a requirement for higher brain development as well as to actually be exposed to all that information. A star fairing civilization that can’t see stars isn’t likely to develop and as far as odd spectrums go RF and Xray might be able to see stars but not predators so it unlikely to develop in the first place.
Appendages that allow fine tool development is pretty much a must for incremental technological development also.
Gravity at least at the upper bounds would need at minimum to obey the rocket equation any world with heavier gravity than that would allow that wouldn’t likely to produce a space fairing civilization.
Lower limits might be imposed on powered flight and missile weapons that may be a required developmental phase also.
And as far as planetary makeup goes then again should be rather similar including likely evolutionary phases that would produce large fossil fuel deposits.
Atmospheric oxygen is also a must no oxygen no fire.
As for as other elements enough metals to support a technological civilization as well as possibly enough fissile material for at least a partial nuclear phase tho lack of fissile material might put developmental pressure on the fusion part of the tech tree so there is some wiggle room.
Similarly, the needs for human-like vision or specific tool manipulation may be limiting our analysis. Consider how bats and dolphins build sophisticated mental models of their world through echolocation, or how octopodes demonstrate problem-solving abilities with fundamentally different appendages than ours.
Given we only have one example of technological civilization, we should be cautious about declaring which features are truly universal requirements versus those that just happened to work for us. There might be paths to advanced technology that we haven't yet conceived.
This is very, very, very much "in your opinion". It's not impossible that you're right, but there is no plausible basis for saying "it is likely".
Maybe I've consumed too much Douglas Adams type of humor
We can't take as evidence the things that happen in chemistry on our planet as indicative of what is likely in the universe.
While the missions remain scientific I absolutely agree contamination must be avoided. But as soon as we cross into the colony phase, wouldn’t that restriction just make things harder?
I think not just harder, because the first colonies will enable scientists to study the pristine environment in more depth, while the colonies itself will be small and costs of a sterilization will be relatively low. So the onset of uncontrolled contamination should probably be delayed until well after the first colony.
Wood should not be damaged by temperatures high enough to kill living cells and it provides negligible shielding for radiation.
However, after sterilization it may require more care than metal, glass or plastic, to avoid any later contamination. Presumably all the assembly must be done in a sterile environment.
Unlike metal or glass, which could be washed in oxidizing acids to remove organic substances, sterilized wood may contain dead bacterial cells in its pores. For satellites expected to burn on reentry that would not matter. For exploring other planets, that would be undesirable, as this could provide false positives for detectors of organic substances.
Yep, in NASA's planetary protection guidelines they have bakeout timelines specified for microbial reduction at temperatures between 112C and 155C. There are a number of other cleaning and sterilization methods in there as well.
[0] https://planetaryprotection.jpl.nasa.gov/resources/img/conte...
In addition to vacuum exposure to address outgassing, they'd probably hit wood with some sterilization process (gamma radiation as one example) to ensure any microbes in the wood are dead before landing on another planet.
I've used it for knife handles. It's light and strong, so that makes sense for this use case.
Maybe, not what is being reported by Sky News though
I'm sure this is kiln dried so the organic volatiles have been mostly driven off.
https://scifi.stackexchange.com/questions/250692/disgusting-...
'The Integral Trees' also had trees in space.