The goal of this new initiative, costing US$1.5 billion for the next 10 years, is to develop scientific understanding necessary to enable the US and other global participants to effectively address these aspects of the sun-earth system, according to Dr Madhulika Guhathakurta, chief programme scientist, Nasa headquarters, Washington.

This was for the first time that Nasa has taken such a project to study how the sun affects/acts on the day to day life on earth in a 11-year solar cycle, she said.

Delivering a talk on `LWS' at the `International Chapman Conference on Storm-Substorm Relationship' which concluded at Lonavala near here on Friday, she said, in the past, all Nasa missions were driven by fundamental science questions.

But this mission would be different in finding the aspects that affect life of living things on earth in real time like human radiation exposure, climate change (past and future), surface warming, ozone depletion and recovery, Guhathakurta said adding that ``we want generous participation from India and other countries.''

The first mission of this project is a `solar dynamics observatory' and is expected to be launched in 2006, she added. The objectives of the programme include identifying and understanding variable sources of mass and energy emanating from the sun that cause changes in the environment with societal consequences, including the habitability of earth, use of technology and the exploration of space, Guhathakurta said. "We will also identify and understand the reactions of geospace regions whose variability has societal impact and space weather hazards," she said. It would extend our knowledge and understanding and would help to explore extreme solar-terrestrial environments and implications for life and habitability beyond earth, especially in moon and Mars, she added.

(PTI)