#5 May 1987
Section 220.127.116.11.005.of the Artemis Data Book
On the Moon, exiting an airlock in a space suit is something that
architecture and engineering will both seek to make as unnecessary as
possible. This for two reasons. First the high Lunar vacuum ( 10E-12 torr
daytime facing the solar wind, 10E-14 torr nighttime sheltered from
the solar wind ) is a precious industrial and scientific resource especially
in combination with the Moon's substantial gravity. Opening airlocks for
exit or entry and purging atmosphere into the vacuum, if done frequently
enough, will degrade the vacuum to a point that the solar wind
can't restore through its flushing action. Second, the nitrogen used as a
buffer gas and biogenic ingredient in the colony's atmospherule must be
imported and therefore must be conserved. Making up for preventable losses
could well tax the colony's capacity for growth.
M IS FOR MIDDOORS:
On Earth we have been familiar with the distinction between indoors and
outdoors for many thousands of years. In the last two decades or so, a new
environment, the middoors, has become familiar to most of us in the form of
the enclosed, climate-controlled streets and plazas of many a shopping mall.
The "landscaped", sunlit central atrium in some new hotel and office
buildings offers another class of examples.
In Lunar cities, except to enter and exit those (e.g. industrial) facilities
which for safety's sake must keep their air unmixed with that of the city at
large, it will be possible to go most anywhere without donning a space suit.
Homes, schools, offices, farms, factories, and stores will exit, not to the
airless, radiation-swept surface, but to a pressurized, soil-shielded,
indirectly sunlit grid of walkways, residential streets, avenues, and
parkways, parks, squares, and playgrounds.
While the temperature of traditionally indoor places could easily be
maintained at "room comfort" levels, that of the interconnecting middoors of
the city could be allowed, through proper design, to register enough solar
gain during the course of the long Lunar day (dayspan), and enough radiative
loss during the long nocturnal period (nightspan) to fluctuate 10 degrees F
on either side, for example from 55-85 degrees F during the course of the
month. "The Great Middoors" could be landscaped with plants thriving on this predictable
variation. This would be both invigorating and healthy for people, plants,
and animals alike, providing a psychologically beneficial monthly rhythm of
tempered mini-seasons. Of course the middoors could also be designed to
keep a steady temperature. But oh how boring that would be!
M IS FOR MATCHPORT:
To go from one Lunar city to another, or from the city to the space port or
other outlying installations, or to transfer from one vehicle to another,
all vehicles and city docks or marinas will be equipped with standardized
matchports or interlocks. These will probably be of unisex design rather
than male-female, and with either able to do the necessary aligning for
safety's sake ( although there will undoubtedly be protocols ). When the two
matchports are aligned and locked ( vehicle-vehicle or vehicle-city ), the
narrow -- hopefully less than 1 cm -- vacuum gap will be slightly over-pressurized
allowing port doors to unseal and open easily inward ( into vehicle, into city ).
Prior to disengagement, the port doors closed, the narrow inter-door gap
would first be flushed with pure oxygen and then this would be pumped out (
into vehicle, into city ) to provide a low grade vacuum which would seal
both port doors by internal pressure ( vehicle, city ) allowing the vehicle to
pull back its matchport and depart, with the escape to the outdoors of only
a minuscule amount of cheap oxygen -- no precious nitrogen would escape.
There would probably be three common matchport sizes: for personal surface
vehicles, for public surface transports, and for cargo rigs. Outside of
safety drills held periodically, perhaps most Lunans will live and travel
widely about the Moon without ever putting on a spacesuit. It won't be necessary.
Contents of this issue of Moon Miners' Manifesto