The territory ahead – Part I

  • The territory ahead - Part I
  • Kepler
  • Phoenix
  • Habitat
  • New Horizons
  • Tom Wolfe. Photograph by Gregg Segal
Date:30 September 2007 Tags:, , , , , ,

The first half-century of space exploration was stunning, from Sputnik to moonwalks to interplanetary probes. The next 50 years promise even more awe-inspiring milestones: life-seeking rovers, a lunar base, and the ultimate off-Earth adventure – a colony on Mars

The first man-made object in orbit didn’t look like much. An aluminium sphere 58 cm across, it was filled with pressurised nitrogen and carried two small transmitters that beamed wavering radio signals to the planet below. On day 22, the batteries ran out and the satellite fell silent. A few weeks later, the craft probably vaporised as it plunged back to Earth.

To Americans at the height of the Cold War, the Soviet Union’s launch of on 4 October 1957 came as a shock – and a spur. The competition that would inevitably be known as the space race was on. Small orbs carrying transmitters were soon followed by larger ones carrying men. And, within a mere dozen years, human beings left footprints in the dust of the Moon.

But then, after a handful of lunar missions, America lowered its sights. For the past 35 years, manned spaceflight has been limited to low Earth orbit. “Part of the problem is that, in the big picture, was premature,” says astronaut Buzz Aldrin. “It was a spurt of progress artificially stimulated by the race to beat the Russians.”

Today, with the Cold War long over and co-operation with Russia an everyday event in space, America is making bold plans again: private space missions, a lunar base and, ultimately, the long haul to Mars. And with those big ambitions come big questions: what is the proper balance between manned and unmanned exploration? Is long-term spaceflight too risky for humans? Is it worth the cost?

For this special issue, POPULAR MECHANICS commemorates the first 50 years of spaceflight by looking ahead to the next half-century. It will be in these coming decades – within the lifetime of most of us now living – that human beings make the transition from earthbound creatures to a space-faring people.
– James B Meigs

How we’ll live on the Moon
A former shuttle astronaut explains what life will be like on Nasa’s future lunar base

“HARDSCRABBLE” was what future president Ulysses S Grant named his ramshackle homestead on the pre-Civil War Missouri frontier. That might be an apt title for Nasa’s planned lunar outpost, for its residents will find the Moon a harsh place to settle. Survival will depend on their ability to evade micrometeoroids, extract oxygen from rocks, and even, like Grant, grow wheat.

The space agency announced its strategy to return to the Moon last December. Instead of emulating the series of six landings, it chose as its initial goal the establishment of a single lunar outpost. Using the new crew exploration vehicle, Orion, Nasa plans to send four astronauts to the Moon as early as 2020 (“Mission: Moon,” April 2007). Eventually, four-man crews will rotate home every six months. Their goal will be to live off the land, extend scientific exploration and practice for an eventual leap to Mars.

The Moon, says Nasa, is the place to get our spacesuited hands dirty. “The lunar base is part of an overall plan that has legs… that makes sense,” says Wendell Mendell, chief of the Office of Lunar and Planetary Exploration at Johnson Space Centre.

“We’re moving the human species out into the solar system.”

Choosing a homestead
The landings from 1969 to 1972 were restricted by fuel limitations to destinations fairly close to the lunar equator. This time, Nasa is drawn to the practical and scientific attractions of the lunar poles. Temperature is one factor: at the poles, the Sun’s slanting rays produce a moderate daylight range of minus 30 to minus 50 degrees Celsius, compared with the equatorial high of 132 degrees.

But the real advantage of the poles is access to resources. Near the south pole, for example, some high crater rims are bathed in nearly constant sunshine. Sun-tracking solar arrays placed there would provide steady power and charge storage batteries to supply electricity during the brief periods of darkness.

An even more valuable resource may lie in the craters’ depths. Spacecraft data suggest they could harbour hundreds of millions of tons of water ice, accumulated from billions of years of comet impacts. Using a simple electric heater, robot ice miners could free water for drinking and agriculture. Electrolysis could break it down further, supplying oxygen for breathing and hydrogen fuel for Moon-to-Earth transportation.

The , to be launched late next year, will search for ice just beneath the Moon’s surface. Another mission, the , will crash a spacecraft into one of the lunar poles in early 2009 and analyse the debris plume for water and other chemical compounds.

If the Moon proves to be dry, which ground-based radar suggests, oxygen can still be pried out of lunar volcanic rock. Combining hydrogen gas brought from Earth with the mineral ilmenite, then heating the mixture to 900 degrees, produces iron, titanium dioxide and water. Other chemical processes can also release oxygen from rocks, given enough heat and electricity.

Lawrence Taylor, director of the Planetary Geosciences Institute at the University of Tennessee, is developing a magnetic “vacuum” hose to suck lunar dirt into a dump truck or pipeline leading to an oxygen extraction plant. At first, the power for these industrial processes would come from lightweight solar arrays. A compact nuclear reactor, tucked safely into a shallow crater away from living quarters, might be needed later.

The south pole is also scientifically attractive. It lies within the South Pole-Aitken Basin, the largest impact crater in the solar system. This 12 km-deep, 2 400 km-wide depression, gouged out by a titanic asteroid or comet impact, should harbour bedrock excavated from deep within the lunar crust. Mike Duke, a retired Nasa scientist, suspects that it also holds samples of impact melts – igneous rocks formed from the collision’s molten splash. Examining those rocks would open a window into the Moon’s ancient history.

Living on a hostile moon
How will residents cope with the hazards littering this airless, blasted body? Arriving crews will unload pressurised habitation modules, like those on the International Space Station (ISS), or perhaps inflate living spaces made of a tough, Kevlar-like fabric.

For protection from cosmic rays and micrometeoroids, the pioneers could bury their habitats in trenches or heap lunar soil over them. With no atmosphere or magnetic field to shield them, as on Earth or Mars, lunar explorers will need to retreat to these shelters during a solar flare’s deadly shower of charged protons. A lucky find might be a lava cave to insulate the living quarters.

Exploring the surface will require a better spacesuit than the one I used as an astronaut to help assemble the ISS in 2001. That suit was too stiff at the waist for easy walking or bending, and its glass fibre torso and bulky life-support backpack made it top-heavy. The old suits wouldn’t cut it, either: the gloves were clumsy, even painful after prolonged use, and the suits so stiff in the waist and knees that crews found it nearly impossible to reach for a rock.

Dean Eppler, a senior scientist at Science Applications International, a private firm in Houston, has spent hundreds of hours in prototype spacesuits, working out the kinks. “The Moon suit is a work in progress,” Eppler says, but “compared with , it will have more flexibility for walking, bending and grabbing stuff off the ground, and be much more intuitive to work in”. Lighter electronics and improved life-support systems should keep the weight between 68 and 90 kg, or just 11 to 16 kg in lunar one-sixth gravity.

Future explorers will also need an improved version of the lunar rover, whi
ch two astronauts could drive about 60 km before its silver-zinc batteries were exhausted. A new model might use solar rechargeable batteries, or electricity from hydrogen-oxygen fuel cells.

Both spacesuits and machines will have to cope with lunar dust: gritty, sharp-edged, and murder on seals and bearings. Engineers hope to use electromagnetic filters and shielding systems to prevent dust from working into critical components.

Taylor is also developing a microwave-powered paving machine capable of reducing damage by turning lunar soil into hard landing pads or roads.

To minimise the number of costly cargo shipments, the outpost will need efficient recycling technology.

Wastewater, including urine, will be returned to a drinkable state using systems soon to be tested on the ISS. Carbon dioxide will be removed from the atmosphere using a catalytic scrubber that recovers some oxygen. But a lunar greenhouse will offer the biggest benefit.

A few plants have been grown experimentally on the ISS, but never on a scale large enough to produce usable oxygen or food. The Moon’s steady polar sunlight would be ideal for greenhouse agriculture. Chris Brown, a plant biology professor at North Carolina State University, leads a group that has been experimenting with ways to grow lunar-ready white potatoes, soybeans and wheat.

“Plants doing photosynthesis are fundamental to life on Earth,” Brown says. “The same system should enable us to colonise other worlds.” The brightly lit greenhouse at the US Amundsen-Scott South Pole Station is popular with those wintering over in Antarctica, providing humidity, fresh food and visual relief from the six month-long night. A greenhouse, coupled with radio and TV contact with Earth, might be just the tonic for lunar pioneers living 384 000 km from home.

Big plans, tight budgets
The US Congress has endorsed Nasa’s lunar goals, but has not provided much money to get the effort moving. The space station and have taken priority over research for outpost technology, space agriculture, advanced life support, nuclear power, rovers, and the crucial robot precursors. There’s also no guarantee that Congress will approve Nasa’s big-ticket hardware: the heavy cargo rocket and the lunar lander.

Funding may well prove the biggest hurdle. “We know how to explore the Moon,” says geologist and astronaut Harrison Schmitt. “In fact, we are far, far better prepared to explore this nearby body… than were Lewis and Clark as they planned to head west into the new Louisiana Territory. We must go back.”

The new lunar base
Moderate temperatures, nearly perpetual sunshine, flat landing areas and subterranean resources make the rim of the Shackleton Crater – situated within the solar system’s largest impact crater, down near the Moon’s south pole – an ideal location for a lunar homestead. Nasa hopes to send the first pioneers there by 2020.
By Jancy Langley

Living quarters sit high on the crater rim so that power-generating solar cell arrays are in constant sunlight. Inflatable modules – light and easy to transport – could be coupled with a fabric that hardens in the area’s abundant UV light. Another option: bury structures in regolith – the Moon’s powdery rock surface – to protect pioneers from potentially deadly solar flares and to equalise internal and external pressure on walls.

Separated from the base’s transmissions, and shielded from Earth’s radio noise, this site holds optical and radio telescopes used to search for extrasolar planets, as well as an ultraviolet telescope that uses the Moon’s rotation to survey for planets like Earth.

At about R55 000 a kilogram, lunar shipping costs force the outpost to mine and manufacture much of its own materials. In the crater basin, miners extract oxygen from ice crystals deposited by comets or asteroids. Strip-mined regolith yields nitrogen for farming, calcium for cement, and hydrogen-free silicon to make glass and ceramics structurally superior to any made on Earth. The soil also holds titanium, iron and aluminium.

To protect the outpost from dust kicked up during take-offs and landings, the pad sits at a lower elevation. The lunar lander shuttles passengers to and from the orbiting transfer vehicle.

They, robots
Unmanned spacecraft will continue to grab the data, if not the spotlight
By David Noland

Between the International Space Station, the space shuttle and, now, the crew exploration vehicle, manned missions

Tom Wolfe
Author,

The purpose of the space programme is not to maintain superiority in space but to build a bridge to the stars before the Sun dies. Homo loquax (man speaking) or Homo sapiens (rational man) is the

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