Security-related work stoppage at Los Alamos could make crucial delivery late and delay first New Frontiers mission
The radioisotope thermoelectric generator (RTG) for the New Horizons Pluto-Kuiper Belt (PKB) mission will not be ready in time and could delay the planned 2006 launch by a year, says NASA. This would add several years to the probe's flight, delaying its planned 2015 arrival at Pluto and its geostationary moon Charon.
Delivery has been delayed by a security-related work stoppage at Los Alamos National Laboratory, New Mexico, where the generator's Russian-made plutonium 238 pellets are to be processed.
NASA may have to accept an RTG that is not fully fuelled, with the reduction in power available requiring a stripped-down spacecraft.
If the RTG is delivered later than December, the launch could be threatened. The PKB spacecraft is scheduled to make a gravity-assist fly-by of Jupiter in February 2007 and is expected to reach Pluto and Charon in July 2015. If the probe arrives much later, Pluto will be heading into years of darkness at the apogee of its elliptical orbit of the Sun.
The Johns Hopkins University Applied Physics Laboratory-led New Horizons is the first mission in NASA's New Frontiers programme, which is intended to conduct fixed-price, cost-capped, medium-class missions to address high-priority Solar System exploration initiatives. Management of the New Frontiers and lower-cost Discovery programmes has been moved from NASA headquarters to the Marshall Space Flight Center in Alabama.
Scientists say they expect to see weather in Pluto's atmosphere, a moon of frozen ice and, potentially, objects as big as the core of Jupiter in the Kuiper Belt.
NASA's Cassini Saturn probe, meanwhile, has discovered two new moons orbiting the ringed planet. The moons are roughly 3km (1.9 miles) and 4km across, respectively. They are 194,000km and 211,000km from Saturn, between the orbits of the moons Mimas and Enceladus.
NASA has issued requests for information seeking ideas on ways to fulfil two key recommendations of the Aldridge commission on implementation of US space exploration policy: increasing the presence of private industry in space operations; and increasing the agency's access to private-sector technology.
TIM FURNISS / LONDON
Source: Flight International
