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.
The Shetland Islands have a maritime sub arctic climate with long mild winters and short cold summers. The climate is moderate because of the influence of the warm sea water. During the winter months temperatures will be 5 degrees on average. During the months of March and April temperatures may rise over 10 degrees Celsius. Summers are relatively cold with temperatures around 20 degrees on average. The warmest month on record had an average temperature of 27.2 degrees Celsius.