NASA's New Millennium programme will create new technologies for future missions.


NASA SAYS THAT ITS NEW WAY of doing things is "smaller, faster, better, cheaper". The US space agency's $100 million-a-year "New Millenium" programme is directed especially at achieving the "smaller and better" part - creating and validating the essential technologies and capabilities required for interplanetary and Earth-science missions for the 21st century.

Missions such as the Jupiter-bound Galileo, are "...driven by technology", says Richard Howard of NASA's Space Science office, "but New Millenium is about identifying the technologies that are absolutely necessary to do new science missions." He says that NASA is looking at a tenfold improvement in power, weight reduction and cost.

NASA envisages a programme of between ten and 15 affordable frequently launched, "micro" missions, with highly focused science, astronomical and astrophysical objectives. Some craft will travel in armadas in precisely controlled formations.

New Millenium technologies and products required for these missions, include ultra-light structures for smaller, lighter (but more versatile) computer-designed spacecraft; an active pixel sensor described as a "camera on a chip", a micro-seismometer the size of a US 25¢ coin (25mm diameter), an ion-drive propulsion system to make the missions "faster", miniaturised communications antennae possibly employing inflatable, deployable, designs, advanced gallium-arsenide and other types of solar arrays; lithium-polymer batteries; and independent decision-making and navigation computer technologies, to make "smart" spacecraft.

The first New Millenium spacecraft has been ordered from Spectrum Astro at a cost of $30 million by NASA's Jet Propulsion Laboratory (JPL), which has project-management responsibility. The 100kg New Millenium 1 will probably be used for a comet and asteroid fly-by and perform its mission rapidly at a speed of 10km/s by using a 260mm-diameter ion-drive thruster developed by NASA and the Ballistic Missile Defense Organization.

The thruster expels high-velocity beams of xenon gas, ionised using electricity from the craft's solar arrays. The New Millenium 1 will carry a miniaturised imaging spectrometer to produce chemical maps of the asteroid and comet. New Millenium 2 and 3 craft are also planned, and the three craft may be launched by 1999. The second craft may be a Mars lander and the third, an interferometer mission (see box). "The prime objective for the missions is not science, but the technology," says Howard.

The interferometer mission will involve constellations of craft, flying in precisely controlled formation to co-observe objects, making exact measurements. This technique will create a huge, free-flying, interferometer telescope, designed to detect, characterise and image "extra-solar planetary systems".

Networks of autonomous micro-spacecraft orbiters or landers could be launched for the study of planetary geology, atmospheres and climates. Nearer to home, a fleet of craft may be used to study temperature, pollution levels and biomass distribution on Earth. The craft could eventually weigh as little as 5kg, with some consisting simply of coin-sized micro-instrumentation wrapped in a "gossamer" architecture.

These "spacecraft on a chip" will possess high levels of autonomy, allowing extraordinary navigational precision, the equivalent of a basketball being thrown from Washington DC through a hoop in Moscow, without touching the rim, or in real terms, sending a basketball-sized craft to rendezvous with a speeding comet.

New technologies will revolutionise data collection and transmission, as well as navigation. Large dish antennae are now used on spacecraft and on the ground because data are sent by low-energy radio waves. Visible optical light can carry equivalent amounts of data at much shorter wavelengths, requiring smaller antennae.

By using optical communications, an 8m-diameter radio dish could be replaced by one 0.3m in diameter and, by attaching a camera, could be used to sight and position the craft, as well as supplying images. The functions of the three systems - communications, navigation and imaging - are thus compressed into one small, highly efficient instrument.

Critical to the success of the New Millenium will be the creation of collaborative partnerships among NASA centres, government agencies, industry, research and development organisations, and academia. Partners will participate in teams from proposal, design and development, to launch and operate the missions.

Integrated product-development teams, each focusing on a specific technology area, will first identify proposed technologies now in development, which offer the greatest benefits for 21st century space and Earth-science missions. The teams will create technology-development "roadmaps" for key areas, determine the costs associated with advancing each technology, and then organise development and infusion of the technologies into validation flights.

The first five teams - each co-led by a JPL related-technology expert and another from a NASA centre or government agency - will cover autonomy, microelectronics, instruments and micro-mechanical systems, communications, and modular architectures and multi-functional systems (see box).

The space probes will create, through their communications technologies and links with the Earth, a "virtual human presence", enabling everyone, not just scientists and technicians, to "visit" planets, comets and asteroids. The New Millenium will provide educational opportunities for in-depth training and experience for engineers and scientists and will build an infrastructure for widespread computer-based access to discoveries and innovations.

Source: Flight International