GPSSunTanner for iPhone
According to the National Cancer Institute more than 2 million people in the USA is diagnosed with skin cancer in 2012. Protecting your skin from the harmful ultra-violet rays of the sun reduces the risk of skin cancer. This application scientifically determines the ultra-violet exposure of direct sun radiation any where on the globe at any altitude, date and time for any chosen duration. This information will let you take protective actions, like selecting the sun tan lotion with the correct blocking factor and the “safe” duration of the exposure to the direct sunlight while catching some rays!
Accurate prediction of the entire solar spectrum and its ultra-violet component is a fairly complicated problem to solve. GPSSunTanner does this very elegantly on a smart phone or a tablet very quickly.
The first challenge is to calculate the sun’s position very accurately at any location on earth at any date and time. The patent pending capabilities of the “OEA Astronomical and Navigational utilities” does this in seconds, with an incredible accuracy of 0.0003 degrees anywhere on earth, at any altitude, from the South Pole to the North Pole, at any date and time, past future or present!
The second challenge is to calculate the atmospheric attenuation of the solar radiation. There are several widely used empirical curve fit models which approximate the solar power as a function of elevation angle of the sun employing the “air-mass” concept. They all are wave-length and altitude independent; therefore all fail to give an accurate prediction of the solar power, even in the visible spectrum, for any elevation angles of the sun. However, in “GPSSunTanner”, the attenuation of the solar power in the atmosphere is calculated by the numerical solution of the Maxwell’s equations taking the wave-length dependent absorption and Raleigh scattering in the atmosphere into consideration for the entire solar spectrum. Planck radiation law is used to calculate the spectral power density distribution of the sun light in the upper atmosphere, which gives the initial value of the problem. This approach gives very accurate prediction of the entire solar power spectrum, including the ultra-violet range, where scattering is dominant, at any sun elevation angle accurately, from sun rise to sun set for any altitude.
Using the advanced global mapping capabilities provided in GPSSunTanner, one can easily provide the current or any virtual location on earth. Using the GPS, compass and the inclinometer capabilities of the smart phone the current/virtual location and ones orientation to the sun is obtained by just a touch of a button. After a very short simulation time GPSSunTanner will give the detailed exposure information both in scientific terms like W/m2 or in terms of UV Index and easy to relate comparative metrics.
By taking the individual’s skin properties and a “reference” GPS coordinate, like ones home location, by using its advanced global mapping capabilities GPSSunTanner provides “personal relative sun tanning” capability. In this mode the user enters a date, period of sun tanning at the “reference” GPS coordinate. For the current or a virtual GPS coordinate the received ultra-violet power density and its energy (Exposure) for a given time period is calculated and graphically compared to the power and exposure at the reference point. This can be used to determine the blocking factor of a suntan lotion for your protection at that location, date and desired duration for safe sun tanning.
Track the sun, its ultra-violet power and its energy, anywhere at any date at any altitude with “GPSSun Tanner” with its 39 language support. Put some real science to your sun tanning and get a great sun tan with minimal ultra-violet damage and enjoy your beach, skiing or mountain holiday and let us do the complex math for you!
(Continued use of GPS running in the background can dramatically decrease battery life)