Highlights. 1  Acute myocardial infarction is the medical name for a heart attack. 2  A number of different factors may increase your risk for a heart attack, including high blood pressure, high cholesterol, and diabetes.  Call 911 immediately if you believe you or someone you know may have had a heart attack.
The blue color of the sky is due to Rayleigh scattering. As light moves through the atmosphere, most of the longer wavelengths pass straight through. Little of the red, orange and yellow light is affected by the air. However, much of the shorter wavelength light is absorbed by the gas molecules.
With regard to green, you can see a greenish sky at sunrise/sunset. There oftentimes is a narrow band between the blue sky away from the horizon and the red sky at the horizon where the sky appears greenish. The above is a clear sky phenomenon, and it's only a narrow band of the sky that appears green.