Published online by Cambridge University Press: 19 September 2017
We have studied the UV radiation in the range 180 to 330 nm emitted by several stars with planetary systems, in order to determine the constraints on the habitable zones posed by the radiation levels. The observations were taken from the International Ultraviolet Explorer (IUE) and the Hubble Space Telescope (HST) satellites database. The stellar sample was chosen to cover the range of what are usually called solar-type stars, from late F to K stars. We found that the planets discovered around Epsilon Eridani and 16 Cyg B are within both the optical and UV habitable zones.