
There are many small orbital launch vehicles proposed or under development - tectonic
https://orbitalindex.com/archive/2019-11-05-Issue-37/?
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hirundo
Toward the bottom:

> How to make Plutonium
> [[https://www.youtube.com/watch?v=-sh5XZo5wRE](https://www.youtube.com/watch?v=-sh5XZo5wRE)]

tl;dw: First get a few gallons of a (radioactive, poisonous, pyrophoric)
transuranic element called neptunium.

I'm glad this didn't turn out to be an easy DIY video, since that would
probably cause, you know, the end civilization. It's a possible solution to
the Fermi Paradox: A civilization advances until someone posts simple
instructions for making plutonium on shared hive mind storage.

It seems like the best way to evade a similar risk is to get the heck away
from Earth as fast as possible, like the top of this blog post describes. The
fact that a not-small gold rush is developing to do just that is the most
hopeful news I've heard in approximately ever.

~~~
DuskStar
Ehhh, everyone (relevant) already knows the general process for making highly
enriched uranium or Pu-239, and how to make a bomb with it once they get it.
The issue is that actually implementing those things takes a ton of
infrastructure, and until relatively recently that infrastructure was
extremely visible. As gas centrifuges have replaced gaseous diffusion as the
primary method of enrichment, though, the amount of - and visibility of -
required infrastructure to refine uranium has decreased dramatically. 20 years
ago enriching uranium in a cave would have been incredibly impractical, as the
machines were just too large and required too much power. But today... :(

~~~
Animats
You need a nuclear reactor to supply the neutrons for transmutation into
plutonium, so this isn't something you can do at home. That video just shows
the preliminary step of making neptunium slugs to be irradiated.

The processes are all difficult from a chemical engineering standpoint. Most
of the materials involved are toxic or radioactive or corrosive or flammable
or several of the above.

Enrichment plants are smaller now. They used to be city-sized; now they're the
size of a large WalMart.[1] But not garage-sized.

Incidentally, there's a huge glut of depleted uranium in uranium hexaflouride
solution form. Hundreds of thousands of tons. This is what uranium enrichment
plants have left over after they've separated out the good stuff, which is
under 1%. There's not enough demand for depleted uranium to run it through the
chemical process to get metallic uranium out. Potentially it could be used in
breeder reactors, if there were any that worked well.

[1]
[https://earth.google.com/web/@32.43377912,-103.07864954,1041...](https://earth.google.com/web/@32.43377912,-103.07864954,1041.7473604a,875.8466207d,35.00000098y,-0.77948261h,52.75406436t,0r?beta=1)

~~~
jabl
> You need a nuclear reactor to supply the neutrons for transmutation into
> plutonium, so this isn't something you can do at home.

Sure, but a simple graphite reactor for Pu production, like what most current
nuclear weapons states have used, isn't particularly complex.

As you mention, the difficult and expensive part is apparently separating the
Pu from the rest (PUREX). In the West, those plants go for $20 billion a pop,
or about, although a would-be-proliferant could probably make do with
something substantially cheaper.

AFAICS the current thinking is that thanks to centrifuges, nowadays the
easiest path for a rogue state to develop it's own weapon is to use enriched
uranium.

And yes, there's a lot of DU around. Except for kinetic warheads,
counterweights in aircrafts, and such, there's not much use for it. Waiting
for breeder reactors to be deployed on a large scale is the plan in practice,
I suppose.

~~~
Animats
... Thanks to centrifuges, nowadays the easiest path for a rogue state to
develop its own weapon is to use enriched uranium.

Maybe. South Africa used electromagnetic separation. Slow, but it works for a
small number of weapons. Pakistan has both a plutonium and a uranium program,
and they've been plugging away at it since the 1970s. North Korea seems to
have taken the plutonium route first. So did Israel.

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ExodusOrbitals1
There is direct link to a summary done by C. Niederstrasser, Northrop Grumman
engineer:

[https://digitalcommons.usu.edu/cgi/viewcontent.cgi?article=4...](https://digitalcommons.usu.edu/cgi/viewcontent.cgi?article=4118&context=smallsat)

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mrfusion
Could we be at the very beginning of a Cambrian explosion for space
exploration? Exciting times.

~~~
DuskStar
Either that or the beginning of a new dot-com bubble.

Most of those smallsat companies are financially viable on the expectation
that they capture a meaningful fraction of the smallsat market - like 1/5th or
more. They can't all win - and that's assuming _any_ of them win. SpaceX seems
to be planning to own the rideshare market [0], and so unless a customer
_really_ cares about having a particular orbit that's going to be pretty tough
competition.

0: [https://www.spacex.com/smallsat](https://www.spacex.com/smallsat)

~~~
adventured
> Either that or the beginning of a new dot-com bubble.

The dotcom bubble was the start of a cambrian explosion.

Those two events are part of the same process, not wholly separate entities in
which case one is bad and the other is good. They require eachother and cannot
be unlinked. The dotcom bubble was not a bad thing, it was a necessary process
of chaotic, sometimes idiotic, experimentation. It was an extraordinary good.
The total sum of all capital destroyed during the dotcom bubble (which lasted
less than four years) would fit into a corner of Amazon's present market
value.

Unless you want to pretend that humans are all-knowing gods. In which case we
require no experimentation, there are no foolish mistakes possible, no errors
of judgment possible, no irrationalism or over-excitement is possible, no
emotion is possible, no idiots and malevolent actors (eg con-artists) are
possible. And so on.

We should all be hopeful - giddy in fact - if we're about to see a space-
focused dotcom style bubble. Bring on the space bubble, do it right now, let's
get moving with that. That will be truly extraordinary, it will signal what
comes after: a real, massive, sustainable expansion.

The global Internet is beyond a magnitude more valuable - in every way you can
measure it, whether in business transacted, value of tech companies, or how
valuable it is to end users - today than it was at the peak of the dotcom
bubble in 2000.

~~~
WWLink
The naysaying is hilarious and pathetic. Like, let's not throw our best and
brightest at solving these problems. No. That's a waste of money. I KNOW!
LET'S THROW IT ALL AT CRYPTOCURRENCY AND ADVERTISING AGENCIES!! BEST IDEA
EVER!

Most of the funding raised by smallsat and small launch companies is a
rounding error compared to the amount of money tossed at bullshit companies
useless crap.

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nine_k
What I'm waiting for is orbital unlauch vehicles. That is, spacecraft that
methodically collect and comoactify space debris.

As we launch more and more cheaply and frequently, the few thousand miles
above Earth become littered more and more, even with all deorbiting or parking
provisions.

~~~
whatshisface
Most satellites are on orbits that will eventually decay due to atmospheric
drag.

~~~
saagarjha
While this is technically true for all satellites, what's important is the
timescale on which their orbits will decay.

~~~
remarkEon
What is the distribution of the time scale of these orbits though? If 90% of
these things take a couple months (or weeks or days or whatever) to decay and
burn up it seems like a non-issue - or one that can be planned around. If the
fat tail sits further out in time that seems like it could actually become an
issue.

~~~
Rebelgecko
One of the junkiest places in orbit right now is around 800-1000km (mostly
thanks to the Chinese ASAT weapon test 12 years ago and an unrelated collision
between two satellites in 2009. There's also tens thousands of droplets of
irradiated coolant that was ejected from Soviet nuclear reactors in 70s-80s).
At 1000km it can take around 100 years for something to deorbit from drag (can
vary a bit depending on unpredictable space weather events).

1000km is still in Low Earth Orbit, but lower parts of LEO decay more quickly,
e.g. months years or decades depending on the orbit's height.

When you get into orbits higher than LEO (MEO: medium Earth orbit, GEO), the
timescales before something reenters can get more geological. A GPS satellite
(~20,000km up, near the middle of MEO) left to its own devices will stay up
for hundreds of thousands, if not millions of years.

~~~
remarkEon
Thanks for the detailed response. Fascinating. Where do you come across this
information? I’d also love to learn more about this nuclear event from Soviet
spacecraft.

~~~
Rebelgecko
Some of my coworkers do work related to orbital debris. I've learned a little
bit by osmosis (mostly the right jargon to type into Google to get useful
query results).

The Soviet spacecraft were the slightly confusingly named US-A series, also
called RORSAT in English. The Wikipedia article[1] is a good start, but you
can find some more technical info if you search around for papers on "NaK
droplets"

[1]: [https://en.wikipedia.org/wiki/US-A](https://en.wikipedia.org/wiki/US-A)

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Sendotsh
Stealing the swipe action like that is really scummy.

Otherwise it’s a pretty interesting article. Lots of amazing space projects
going on lately.

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plugger
I expect 95% of these projects will never reach orbit.

Here's something tangentially related.

[https://www.youtube.com/watch?v=nuGSTn_F0FE](https://www.youtube.com/watch?v=nuGSTn_F0FE)

~~~
Rebelgecko
I saw a list elsewhere that was tracking ~200 companies building launch
vehicles. I'd guess that 90% of them will be gone in a decade having never put
anything in orbit.

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trianglem
This sounds like it may or may not be true. Is this all because of Elon Musk?

~~~
Robotbeat
Not an insignificant part of it IS because of Elon Musk. SpaceX has been
crazily successful, AND it has a high churn rate, so the know-how gets spread
throughout the industry in startups like these. The latter may be bad for
SpaceX (arguable?), but I think it's good for the industry.

