Aluminum and Nitrogen in asteroids

I am very much a fan of O'Neill colonies, but have long believed they
would be much easier if they were close to a carbonaceous asteroid rather
than the moon. However, it would appear that Aluminum is perhaps the ideal
building material for a space colony and Nitrogen is a major part of any
atmosphere. So does anyone know typical concentrations of either Aluminum
or Nitrogen in near-earth asteroids?

Thanks,

--Larry

"Larry Gales" wrote in message
news:Pine.WNT.4.56.0310022026410.1980@homecomps...
I am very much a fan of O'Neill colonies, but have long believed they
would be much easier if they were close to a carbonaceous asteroid rather
than the moon.

Why?

However, it would appear that Aluminum is perhaps the ideal
building material for a space colony and Nitrogen is a major part of any
atmosphere. So does anyone know typical concentrations of either Aluminum
or Nitrogen in near-earth asteroids?

Nitrogen content quite low due to the orbit - no atmosphere and no ice to
keep the nitrogen frozen.

As for aluminium, the concentration would probably be similar to the Moon.
--
Alan Erskine
alanerskine(at)optusnet.com.au

Trial or release, Mr Bush, trial or release.

In article Pine.WNT.4.56.0310022026410.1980@homecomps,
Larry Gales wrote:
...However, it would appear that Aluminum is perhaps the ideal
building material for a space colony and Nitrogen is a major part of any
atmosphere. So does anyone know typical concentrations of either Aluminum
or Nitrogen in near-earth asteroids?

Well, nobody really knows the concentration of *anything* in near-Earth
asteroids, not for sure. We have some vague optical evidence for the
likely composition of the outermost micron, and for the single case of
Eros we have limited gamma-ray-spectrometer data going down a meter or so.
And we can analyze meteorites, but there are still major questions about
their exact relationship to asteroids.

That said...

Aluminum is abundant in some types of rocks, but those types aren't that
common in meteorites. Find the right asteroid and you'd have plenty,
otherwise it's a relatively minor constituent. Getting it out is a lot of
work, mind you, and very energy-intensive.

Nitrogen is absent or rare in most meteorite types, except carbonaceous
chondrites, which have quite significant amounts of it.
--
MOST launched 1015 EDT 30 June, separated 1046, | Henry Spencer
first ground-station pass 1651, all nominal! |

Larry Gales wrote:

I am very much a fan of O'Neill colonies, but have long believed they
would be much easier if they were close to a carbonaceous asteroid rather
than the moon.

In more recent years, some SSI fellows have suggested that the first space
habitats may get built adjacent to NEOs of the CC variety. Me, I still tend to
assume they'll get built in HEO because I expect them to get built in support
of a market, and I expect that market to be in cislunar space. But I could be
wrong.

However, it would appear that Aluminum is perhaps the ideal
building material for a space colony and Nitrogen is a major part of any
atmosphere. So does anyone know typical concentrations of either Aluminum
or Nitrogen in near-earth asteroids?

Building from asteroidal resources rather than lunar would probably push you
toward a steel structure rather than aluminum. The moon is no slouch when it
comes to providing nickel and iron, but some asteroids are nearly all
nickel-iron.

I don't think the asteroids are exactly brimming over with nitrogen, but
they're certainly better sources of nitrogen than the moon.

But I wouldn't worry a lot about the weight of the nitrogen. The atmosphere
will occupy an impressively large volume, but it won't weigh a lot compared to
the weight of the shielding, structure, and topsoil.

--


Regards,
Mike Combs
----------------------------------------------------------------------
We should ask, critically and with appeal to the numbers, whether the
best site for a growing advancing industrial society is Earth, the
Moon, Mars, some other planet, or somewhere else entirely.
Surprisingly, the answer will be inescapable - the best site is
"somewhere else entirely."

Gerard O'Neill - "The High Frontier"

Larry Gales writes:

I am very much a fan of O'Neill colonies, but have long believed
they would be much easier if they were close to a carbonaceous asteroid
rather than the moon. However, it would appear that Aluminum is perhaps
the ideal building material for a space colony and Nitrogen is a major
part of any atmosphere. So does anyone know typical concentrations of
either Aluminum or Nitrogen in near-earth asteroids?

There is not likely to be much in the way of Nitrogen on most Near-Earth
Asteroids, since the majority of nitrogen compounds tend to be rather
volatile, and will have long since boiled off. You need to look at
short-period comets, which have substantial nitrogen in the form
of ammonia. (Caveat: A few NEAs might actually be "dead comets,"
but they are not likely to have that much ammonia left in them.)

As for aluminum, it is a quite abundant element, and most "stony" asteroids
are likely to have quite a lot of it...


-- Gordon D. Pusch

perl -e '$_ = \n"; s/NO\.//; s/SPAM\.//; print;'

On Fri, 3 Oct 2003, Alan Erskine wrote:

Date: Fri, 3 Oct 2003 23:27:32 +1000
From: Alan Erskine
Newsgroups: sci.space.tech, sci.space.policy
Subject: Aluminum and Nitrogen in asteroids

"Larry Gales" wrote in message
news:Pine.WNT.4.56.0310022026410.1980@homecomps...
I am very much a fan of O'Neill colonies, but have long believed they
would be much easier if they were close to a carbonaceous asteroid rather
than the moon.

Why?
------------------------------------------------
(a) Asteriods have a much more varied chemical composition than the
Moon, and large amounts of water and carbon, and more Nitrogen than
on the Moon
(b) Flinging topsoil off an asteroid with 0.01% of earth's gravity
at 5 m/s and aiming it at a target 5 km away is vastly
easier than catapulting it to over 2000 m/s to a precise location
over 100,000 km away
(c) The asteroid requires almost no dV for landing and escape and has
a huge amount of rocket fuel (steam or LH2/LOX) readily available
(d) Returning PGM metals from an asteroid is far easier and much more
likely to happen than building solar power satellites
for an economic return
------------------------------------------------



However, it would appear that Aluminum is perhaps the ideal
building material for a space colony and Nitrogen is a major part of any
atmosphere. So does anyone know typical concentrations of either Aluminum
or Nitrogen in near-earth asteroids?

Nitrogen content quite low due to the orbit - no atmosphere and no ice to
keep the nitrogen frozen.

----------------------------------
I was not thinking of free Nitrogen, but minerals or compounds with
Nitrogen

-- Larry
--------------------------------------------



As for aluminium, the concentration would probably be similar to the Moon.
-----------------------------
I think it is much less than the Moon, but how much less I don't know

--------------------------------------



--
Alan Erskine
alanerskine(at)optusnet.com.au

Trial or release, Mr Bush, trial or release.

On 04 Oct 2003 21:05:44 -0500, (Gordon D.
Pusch) wrote:

Larry Gales writes:

I am very much a fan of O'Neill colonies, but have long believed
they would be much easier if they were close to a carbonaceous asteroid
rather than the moon. However, it would appear that Aluminum is perhaps
the ideal building material for a space colony and Nitrogen is a major
part of any atmosphere. So does anyone know typical concentrations of
either Aluminum or Nitrogen in near-earth asteroids?

There is not likely to be much in the way of Nitrogen on most Near-Earth
Asteroids, since the majority of nitrogen compounds tend to be rather
volatile, and will have long since boiled off. You need to look at
short-period comets, which have substantial nitrogen in the form
of ammonia. (Caveat: A few NEAs might actually be "dead comets,"
but they are not likely to have that much ammonia left in them.)

As for aluminum, it is a quite abundant element, and most "stony" asteroids
are likely to have quite a lot of it...

Additionally, for some reason, many O'Neill enthusiasts seem to like
the open interior (Big Can), but IMO, this causes more problems than
it is worth in many respects. Many aspects are made much simpler if
you shorten the cylinder, and roof it. Sort of like a stretched
Stanford Torus.

Alan Erskine wrote:
"Larry Gales" wrote in message
news:Pine.WNT.4.56.0310022026410.1980@homecomps...

I am very much a fan of O'Neill colonies, but have long believed they
would be much easier if they were close to a carbonaceous asteroid rather
than the moon.


Why?

Here is one of my arguments for near earth asteroids:
http://www.clowder.net/hop/railroad/Gravitywells.jpeg

Another is, being recent immigrants from the outer solar system, they
are likely to be much more volatile rich than the moon. Air, water and
fuel might be easier to come by.



However, it would appear that Aluminum is perhaps the ideal
building material for a space colony and Nitrogen is a major part of any
atmosphere. So does anyone know typical concentrations of either Aluminum
or Nitrogen in near-earth asteroids?


Nitrogen content quite low due to the orbit - no atmosphere and no ice to
keep the nitrogen frozen.

As for aluminium, the concentration would probably be similar to the Moon.


It's thought that a good fraction of the asteroids are former comets
(One asteroid, 1979 VA, was actually seen as a comet with a tail in an
earlier sighting when it was named Wilson Harrington)

David Brin (he was a planetary scientist before becoming an sf writer)
speculated that as a comet's surface volatiles boil off, they leave a
tarry residue that is an excellent insulator protecting the remaining
volatiles at the center of the once outgassing comet.

1979 VA and Nereus are two asteroids thought to be ex-comets. Perhaps
there is ammonia in their interiors as well as water and some hydrocarbsons.

Hop
http://clowder.net/hop/index.html

In sci.space.policy Henry Spencer wrote:
In article Pine.WNT.4.56.0310022026410.1980@homecomps,
Larry Gales wrote:
...However, it would appear that Aluminum is perhaps the ideal
building material for a space colony and Nitrogen is a major part of any
atmosphere. So does anyone know typical concentrations of either Aluminum
or Nitrogen in near-earth asteroids?

Well, nobody really knows the concentration of *anything* in near-Earth
asteroids, not for sure. We have some vague optical evidence for the
likely composition of the outermost micron, and for the single case of
Eros we have limited gamma-ray-spectrometer data going down a meter or so.
And we can analyze meteorites, but there are still major questions about
their exact relationship to asteroids.

Radar returns also, from one or two, which may again give information about
the first little bit.

--
http://inquisitor.i.am/ | | Ian Stirling.
---------------------------+-------------------------+--------------------------
"Melchett : Unhappily Blackadder, the Lord High Executioner is dead
Blackadder : Oh woe! Murdered of course.
Melchett : No, oddly enough no. They usually are but this one just got
careless one night and signed his name on the wrong dotted line.
They came for him while he slept." - Blackadder II

Trakar wrote:
On 04 Oct 2003 21:05:44 -0500, (Gordon D.
Pusch) wrote:


Larry Gales writes:


I am very much a fan of O'Neill colonies, but have long believed
they would be much easier if they were close to a carbonaceous asteroid
rather than the moon. However, it would appear that Aluminum is perhaps
the ideal building material for a space colony and Nitrogen is a major
part of any atmosphere. So does anyone know typical concentrations of
either Aluminum or Nitrogen in near-earth asteroids?

There is not likely to be much in the way of Nitrogen on most Near-Earth
Asteroids, since the majority of nitrogen compounds tend to be rather
volatile, and will have long since boiled off. You need to look at
short-period comets, which have substantial nitrogen in the form
of ammonia. (Caveat: A few NEAs might actually be "dead comets,"
but they are not likely to have that much ammonia left in them.)

As for aluminum, it is a quite abundant element, and most "stony" asteroids
are likely to have quite a lot of it...


Additionally, for some reason, many O'Neill enthusiasts seem to like
the open interior (Big Can), but IMO, this causes more problems than
it is worth in many respects. Many aspects are made much simpler if
you shorten the cylinder, and roof it. Sort of like a stretched
Stanford Torus.


This is my view:
http://www.clowder.net/hop/railroad/ChengHo.html
A series of modular Stanford tori can be stacked to make a cylinder.

This way you can eventually have a large cylinder. But you don't have to
wait for the whole cylinder to be finished before you start enjoying the
new real estate.

Roofing it reduces the mass of air needed. The hollow space inside is a
good place to put an axial mirror. I favor axial mirrors because the
outer windows of O'Neill colonies would be subject to much more psuedo
gravity stress and micrometeor impacts. Better that the entire outer
hull be a strong, non brittle material (which excludes glass and other
transparent substances).

In another post Larry Gales seems to be imagining the habs 5 km from the
asteroid. Why not build it on the asteroid's pole? (as in my
illustration). This way transportation is even easier and the asteroid
itself is a radiation shield for almost 2 pi stradians.


Hop
http://clowder.net/hop/index.html