This can include fabric with an ultraviolet protection factor (UPF) of 30 or more, which means it is tightly woven and helps block UV rays. UV Index of 6 to 7 This is a high level of UV radiation ...

Medically reviewed by Casey Gallagher, MDMedically reviewed by Casey Gallagher, MD The ultraviolet (UV ... uses a computer model to predict the intensity of UV exposure someone will receive ...

The last change in Earth's magnetic field, known as the Laschamps excursion, occurred around 40,000 to 42,000 years ago, during which the magnetic North Pole began to shift over Europe and dropped ...