Final design of a space debris removal system

The objective is the removal of medium sized orbital debris in low Earth orbits. The design incorporates a transfer vehicle and a netting vehicle to capture the medium size debris. The system is based near an operational space station located at 28.5 degrees inclination and 400 km altitude. The system uses ground based tracking to determine the location of a satellite breakup or debris cloud. This data is unloaded to the transfer vehicle, and the transfer vehicle proceeds to rendezvous with the debris at a lower altitude parking orbit. Next, the netting vehicle is deployed, tracks the targeted debris, and captures it. After expending the available nets, the netting vehicle returns to the transfer vehicle for a new netting module and continues to capture more debris in the target area. Once all the netting modules are expended, the transfer vehicle returns to the space station's orbit, where it is resupplied with new netting modules from a space shuttle load. The new modules are launched by the shuttle from the ground, and the expended modules are taken back to Earth for removal of the captured debris, refueling, and repacking of the nets. Once the netting modules are refurbished, they are taken back into orbit for reuse. In a typical mission, the system has the ability to capture 50 pieces of orbital debris. One mission will take about six months. The system is designed to allow for a 30 degree inclination change on the outgoing and incoming trips of the transfer vehicle

Spatial perspectives on voluntarism in learning disabilities services in Ireland

Voluntarism has moved to the centre of most western neo-liberal governments’ focus in terms of welfare delivery. At the same time, very little of the social policy literature has identified specific historical, cultural and political contexts of place in shaping the particular form of voluntarism and the scale at which it takes place in a country. In order to address policy-related issues of the voluntary sector, a geographical perspective focusing on these local contexts can be very useful in unpacking how the sector can exist across regional and local scales. This article explores the rise of voluntarism in adult learning disability services in Ireland. Ireland experienced the ‘community turn’ much earlier than most Western states, in that the state advocated a ‘hands-off’ approach in learning disability services from the outset. It uses data from 40 interviews with local health agencies, voluntary organisations and informal carers. It critically examines the complex geographical factors that have contributed to the particular form of voluntarism that has evolved, thus demonstrating that understanding levels of voluntary activity requires attention to local circumstances