The search for a strategy for mankind to survive the solar Red Giant   catastrophe
  In around 5 gigayears our Sun will grow to a Red Giant and will swallow Earth. The plan is subdivided into two parts: We propose to construct some kind of parasol to shadow Earth. The position of the parasol will be the (inner) Lagrange Point L1. If we want to survive also the time beyond the next 5 Gy, where Suns luminosity and radius increase hundred fold and oscillate until our Sun develops finally into a White Dwarf, we have to shift Earth into the Kuiper Belt (50 AU) by means of the swing-by technique During this journey of about some megayears or more Earth must be illuminated by an artificial light source. A ring of DD-fusion power stations outstretched on Moons orbit should produce the necessary 175 PW of visible light. In the Kuiper Belt Earth will be brought into an orbit of an artificial Sun, an ArtSun formed in the meantime by the fusion of gaseous Jupiter-like planets imported from other planetary systems in the neighborhood 
M. Taube and W. Seifritz