Near Earth Objects (NEOs) are comets or asteroids that intersect or pass near to our planet posing a real and underestimated danger to mankind. While the probability of impact is low, the consequences of such an impact could be apocalyptic. Various programs are underway to discover these kilometer-sized objects from Earth. However, once targets of interest have been identified a fly-by or orbiting spacecraft is required to understand the objects' mass, morphology and composition.Fly-past NEO missions represent the simplest interplanetary missions and need not be high cost. An 'entry level' mission has been conceptually designed able to deliver a 10kg science 'reference' payload to NEO fly-by for a total mission cost (including launch and operations) of Euro20million (FY2003), This paper outlines the platform architecture, cost and cost drivers, and describes the key technology trades to be performed and the developments required to extend current Low Earth Orbit (LEO) technology to a deep space mission. It concludes by identifying the top-level trade-offs to be made in order to enhance the science return of the mission.

The FRISBEE multi-mission platform is presented, alongside the mission concept for SWARM (Space Weather Advanced Research Mission), a fleet of 30 or more microsatellites launched in groups of 5 and covering a range of local times and inclinations. The aim of this mission is to develop an understanding of the dynamic, global, and multiscale solar terrestrial interactions. The scientific payload is restricted to a dc magnetometer and electrostatic charged particle (ion and electron) analyser, providing both high time resolution and characterisation of collisionless plasma processes. The baseline satellite swarm can be launched in a variety of configurations and be augmented by future launches of identical satellites to provide greater coverage and density of measurement. The satellites require only loose formation control to ensure equal separation throughout the set of orbits defined in this document. The individual satellites are spin stabilized and each have a mass < 25 kg. This mission represents the next step in understanding the solar terrestrial interaction and the potential results will be of great interest to the space science community at large. This mission has a true requirement for a swarm such that it can sample the magnetosphere in three dimensions and with sufficient density of measurements. The spacecraft required for this proposed mission could be designed and built within 24 months as most of the platform and payload technologies are re-used from previous missions. The mission has the potential for international collaboration, with provision of spacecraft platforms and world-leading scientific research. A demonstration of this mission has been down-selected by the Particle Physics and Astronomy Research Council (PPARC) for potential funding in the UK National MOSAIC small satellite programme.

CNES is studying in partnership with scientific laboratories and industry the feasibility of a high-resolution ocean topography mission based upon a new class of wide-band, Ka-band altimeter. This paper presents the altimeter/radiometer design and performance as well as results from the breadboard activities. The accommodation on a microsatellite is also shown.

Lunar and interplanetary missions are extraordinarily expensive. Previous missions have cost hundreds of millions of dollars and for this reason were primarily the domain of large national space agencies. However, in recent years a trend has developed in which missions have become more affordable giving rise to a new world of space faring nations. Surrey Satellite Technology Ltd (SSTL) has been at the forefront of providing 'affordable access to space' for a range of Low Earth Orbit (LEO) mission since 1979. Extending this philosophy to a lunar mission will demonstrate a new affordable lunar and interplanetary platform. This paper aims to summarize SSTL's interest and experience of missions beyond LEO. It outlines the current status of he low cost lunar orbiter system design, detailing the principle design drivers, platform budgets including overall mission cost and outline mission level trade-offs which effect cost the most. It assesses low cost launch options and makes a recommendation for a unique initial launch orbit. A practical Earth departure and lunar capture trajectory is proposed along with a cost-effective operations concept. While this research primarily focuses on platform demonstration the opportunity to undertake science has not been overlooked. This design for low-cost approach is challenging. However, the largely commercial off-the-shelf (COTS) system design, in part developed from the successful SNAP-1 nanosatellite avionics, suggests the mission is feasible for both low cost ($25million dollars) and low risk.

Earth Observation satellites have traditionally been expensive to develop and launch and, as a consequence, have been targeted to cover the diverse needs of a large user community. Many niche applications in remote sensing are not exploited to their full potential or operating on a profitable basis and, as a result, space-based Earth Observation has not yet made a similar impact into our everyday lives when compared with satellite communications.