
Brane Craft - protomyth
http://www.nasa.gov/feature/brane-craft
======
ChuckMcM
Well it is out of the box thinking, not sure how practical it is though. Sadly
a paper on "Brane Craft" does not show up on The Aerospace Corp's website,
although Siegfrieds work on cubesats does
([https://www.google.com/url?q=http://www.aerospace.org/wp-
con...](https://www.google.com/url?q=http://www.aerospace.org/wp-
content/uploads/2015/04/Think-Big-Fly-
Small.pdf&sa=U&ved=0ahUKEwjn85_nkorMAhUBU2MKHVNqCjYQFggKMAM&client=internal-
uds-cse&usg=AFQjCNHfgX3casQ0ChFAOfnTh6vT6InQMQ))

One of my favorite "low cost / unconventional" de-orbit ideas was candle soot
clouds. Basically a cloud of carbon black that is deployed in orbit, it coats
objects that pass through it asymmetrically resulting in asymmetric thermionic
emissions when exposed to sunlight, creating a small net impulse which pushes
the stuff out of orbit. Not sure how you would prevent it from killing stuff
you wanted to keep though.

~~~
LeifCarrotson
Wouldn't that only work if the object did not rotate at all?

~~~
ChuckMcM
As I recall the paper covered rotation (all space junk seems to have a
rotational component) the energy comes from solar insolation which is always
in a consistent direction relative to the orbital motion.

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e0m
More things should be described as "propagating through spacetime"

~~~
maaku
Elon's don't propagate through spacetime. They pull the frame of the universe
I the opposite direction.

~~~
dcgoss
I think we should have a new unit of measurement called the Elon. "He traveled
about 45 million Elons at a rate of 25 kiloelons per second"

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RIMR
This is one of those things where I am not sure if I just don't understand the
core concepts, or if the person talking to me is a complete nutter.

Isn't a 'brane' a mathematical object? Is there any basis in science for
turning a physical 3d object into a M2-Brane?

At first read I thought he was just talking about a space probe in the form of
a thin sheet that could propel itself in a novel way. Now I think he's talking
about dropping the ship out of the third dimension.

Can anyone here ELI5?

~~~
chiaro
I assume it's some kind of solar sail.

[https://en.wikipedia.org/wiki/Solar_sail](https://en.wikipedia.org/wiki/Solar_sail)

~~~
foobarbecue
Nope. They describe the propulsion quite clearly. It's solar panels and an ion
drive. The material they are ionizing is a liquid stored between the two
sheets.

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state
I wonder who does the 'graphic depictions' for NASA. Must be quite fun.

~~~
tempodox
I would apply for that position at once.

~~~
eps
Can you depict a black hole that's not black?

That'd be 101 of space illustration.

~~~
tempodox
I'm actually not so sure about that. Either put some non-blackness around a
black circle, or (probably more interesting) obscure the black hole by the
effects of its gravitational lens.

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partycoder
Today is the anniversary of the Vostok 1 launch, the first manned spacecraft.
If anything will make it to the front page of Hacker news today it should be
that.

~~~
captn3m0
Starshot is on the first page, and apparently they timed the PR for the
anniversary.
[https://news.ycombinator.com/item?id=11480840](https://news.ycombinator.com/item?id=11480840)

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sarreph
It'd be pretty cramped onboard the 2D Branecraft

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inopinatus
Yes. It is too small.

Therefore:

The relevant Hugo winner has you & thousands of others uploading your
personalities into on onboard "neural mesh", resulting in everyone calling it
the "Brainship". An in-voyage accident due to forgotten space junk sends you
somewhere unexpected in space and/or time. During the trip the onboard
community fragments and develops in a petri dish of experimental post-
corporeal societies that promptly go to virtual war over control of the craft.
The Bra{in|ne}boat encounters strange new lifeforms, which by a series of
loosely connected plot devices involving convoluted theoretical and/or
fictional mathematics, enable one small motivated group on board to seize
control and return the device to Earth, over the objections of another group.
In the intervening thousands of years, humanity has evolved radically and is
facing destruction due to techno-industrial political forces wielding
unimaginable power. The inhabitants of the Brainevessel join forces and use
the wisdom and/or alien friends they gained during their epic voyage to save
humanity, and the warring factions are subsequently reconciled and redeemed.
One faction stays behind to help humanity recover, whilst the other goes on an
unspecified voyage back to the stars aboard the upgraded Mindyacht. The End.

(c) every science fiction author since Homer.

~~~
taneq
Sounds... Stross-y. :)

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T-A
Yep, that was pretty much Parts II & III of "Accelerando":
[https://en.wikipedia.org/wiki/Accelerando](https://en.wikipedia.org/wiki/Accelerando)

~~~
inopinatus
I'd actually recently re-read Greg Bear's "Eon" and mashed it up with a bit of
Greg Egan. No doubt there'll be echoes of many other novels besides.

~~~
taneq
Given your tagline of "(C) Every science fiction author since Homer" I think
you pretty much nailed it. :D

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noobie
Just out of curiosity, how do satellite launchers account for space debris[0]?

0.[https://upload.wikimedia.org/wikipedia/commons/a/a1/Debris-G...](https://upload.wikimedia.org/wikipedia/commons/a/a1/Debris-
GEO1280.jpg)

~~~
danielvf
"Space is big. Really big. You just won't believe how vastly, hugely, mind-
bogglingly big it is..."

A lot of it comes down to things just being far apart. We're used to the
surface of the earth - a 2D surface, but space is 3D. There's orders of
several orders of magnitude more room and not a lot of objects in it.

Secondly, the orbits of these objects are tracked and in a database. It's a
pretty easy task to check if your planned launch path comes near anything.

~~~
madaxe_again
Space is big, low earth orbit isn't - it's easy to end up with a runaway
debris cloud that completely blocks access to space.

Space will still be really, really big, but short of Jeltz showing up, kessler
syndrome will close our access to space.

~~~
danielvf
Kessler is overhyped. The lower half of low earth orbit isn't a problem
because everything there falls to earth in a year or two unless it is actively
keeps itself in orbit. Outside of LEO, there's massively more room, and
massively less stuff. So the only area we need to consider is "high" LEO.

As a thought expiriment, consider the worst case - a hyper intelligent, pan
dimensional being disassembles all spacecraft in high LEO. let's assume that's
1,000 US tons worth. ( I have no idea.) if these spacecraft pieces were spread
into a sphere the size of the earth, that would be 1/40 billionth of a cm
thick.

Since a sphere doesn't orbit, let's turn it into lethal 1cm cubes, all
magically evenly distributed, orbiting at the same altitude, magically not
colliding. That's one death cube every 4 square Km. What are the odd of flying
a rocket through that layer? Pretty good actually. The layer is only certain
death if you stay in it. We'd still have access to the solar system,
geosynchronous orbit, and mid/low LEO even in the alien intelligence worst
case Kessler syndrome.

( I have only worked this out on the back of a napkin. Corrections to math
appreciated)

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mattbeckman
As CubeSats and FemtoSats are picking up support, we need LEO trash collectors
even moreso.

~~~
grinich

        LEO trash collectors
    

doesn't the atmosphere do a good enough job? seems that most things in LEO
will decay within a few years

~~~
CapitalistCartr
Unfortunately no. The curent amount is already serious and, if we were
continue at our past rate, we'll make space inaccessible.

Orbital Debris Quarterly is a good resource on the subject.

[http://orbitaldebris.jsc.nasa.gov/newsletter/newsletter.html](http://orbitaldebris.jsc.nasa.gov/newsletter/newsletter.html)

~~~
patrickyeon
(I'm not an orbits expert, but I do work for Planet Labs, and we're sending up
piles of cubesats.)

The actors puting objects up in orbit are trying hard to be good neighbours
these days. Our cubesat missions are designed such that should we completely
lose control over a satellite the orbit will naturally degrade and re-enter
the atmosphere on a ~10 year time scale. Our hardware deployed from the ISS is
gone in less than two years. It's my understanding that it is required of us
(and most groups in general) to plan our missions such that they will
naturally de-orbit within 25 years.

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madaxe_again
Nice idea using them for clearing orbital debris, but the $1bn cost of doing
it "conventionally" seems a reasonable price to pay for continued access to
space.

If we don't do something, we will end up trapped on this ball of rock by
lethal kessler syndrome.

Why isn't there legislation mandating that space operators tidy up after
themselves?

Wait, stupid question, we can't get that right even on earth.

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stuaxo
And here I was thinking it would be a craft to travel the multiverse.

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tempodox
I can't decide whether this is a late April fool's joke or just an unorthodox
concept.

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Aelinsaar
The description seems totally at odds with the babble about 2D Branes.

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philip142au
How does it do propulsion?

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whatifbeans
Looks like a magic carpet to me.

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anon5446372
Bane craft - ah, you think darkness is your ally?

