The use of SPICE extends from mission concept development through the post-mission data analysis phase, including help with correlation of individual instrument data sets with those from other instruments on the same or on other spacecraft. The primary SPICE data sets are often called kernels or kernel files.. SPICE kernels are composed of navigation and other ancillary information that has been structured and formatted for easy access and correct use by the planetary science and engineering communities.
Certain eye structures have refractive properties similar to water or lenses and can bend light rays into a precise point of focus essential for sharp vision. Most refraction in the eye occurs when light rays travel through the curved, clear front surface of the eye (cornea). The eye's natural (crystalline) lens also bends light rays. Even the eye's tear film and internal fluids (aqueous humor and vitreous) have refractive abilities. Recommended For You.
Refraction occurs when a beam of light is bent, and is caused by a change in the speed of the beam as it passes from one transparent medium to another.