  The electric solar wind sail (E-sail) propellantless propulsion device uses
long, charged metallic tethers to tap momentum from the solar wind to produce
spacecraft propulsion. If flying through planetary or moon eclipse, the long
E-sail tethers can undergo significant thermal contraction and expansion. Rapid
shortening of the tether increases its tension due to inertia of the tether and
a Remote Unit that is located on the tether tip (a Remote Unit is part of
typical E-sail designs). We analyse by numerical simulation the conditions
under which eclipse induced stresses are safe for E-sail tethers. We calculate
the closest safe approach distances for Earth, Moon, Venus, Mars, Jupiter,
Ceres and an exemplary 300 km main belt asteroid Interamnia for circular,
parabolic and hyperbolic orbits. We find that any kind of eclipsing is safe
beyond approximately 2.5 au distance, but for terrestrial planets safety
depends on the parameters of the orbit. For example, for Mars the safe distance
with 20 km E-sail tether lies between Phobos and Deimos orbits.
