L2-James Webb Space Telescope operationally friendly environment?

Abstract

One of the key components for James Webb Space Telescope (JWST) to meet its science goals is the second Lagrange point (L2) environment. This 'operationally friendly' environment provides JWST a dark, cold, and stable orbit to view the first starlight of the Universe. The environment assists the science instruments with passive cooling, limited stray light, and large contact times with Earth to increase the efficiency of the JWST. Now that JWST is moving into the design/construction phase, we are finding that the initial concepts now require a more detailed examination. We are finding that L2 has some issues that impact cost and operational friendliness. This paper will address some of these L2 environment challenges currently being reviewed: cosmic ray environment, communications, and orbit maintenance and determination. To address the above L2 environment concerns, the JWST spacecraft and science planning system requires adjustment to the onboard 'event driven' planning. As the spacecraft buildup continues, the challenges of communicating from L2 will be met so that JWST will see the first starlight in the Universe. The communication items will be covered in other papers during this conference.