The Simple Answer :   The color of a star's visible light indicates its surface temperature: a relatively cool star glows red (longer wavelength), and very hot ones glow â¦ bluish-white or even blue (shorter wavelengths).
Over the course of the year, the temperature in Shetland typically varies from 37Â°F to 59Â°F and is rarely below 30Â°F or above 63Â°F. The warm season lasts for 82 days, from June 24 to September 14, with an average daily high temperature above 55Â°F. The hottest day of the year is August 6, with an average high of 59Â°F and low of 52Â°F. The cool season lasts for 133 days, from November 26 to April 8, with an average daily high temperature below 46Â°F.
Summers in Shetland are usually showery, bright and cool, winters dark and wild, but also mild. The climate's slightly warmer than the Gulf of Alaska, which lies on the same 60th parallel of latitude. On the fine days, which can occur at any time of year, the islands appear idyllic; in winter hurricanes they're awe-inspiring. But, having said that, when the weather's good you can have a beach all to yourself.