March 14, 2015 is a special date for math lovers and it is being celebrated at NASA and elsewhere in the world. If you write the date out in numbers, you get 31415, which are the first five numbers in pi. Pi, as you may know is the formula for the ratio of a circumference to the diameter of a circle. The appearance of this formula on the calendar only happens once every 100 years. Pi Day is also what would have been Albert Einstein’s 136th birthday.
NASA is a place that uses the formula for pi often since they deal with the volume and surface area of spheres, which happens to include planets and objects in space. Scientists need pi to show that the Earth rotates on its own axis and goes around in a circle that equals 21,000 miles or 34,000 kilometers in its circumference.
In honor of this once in a lifetime occurrence of Pi Day, the Jet Propulsion Lab along with NASA is having a NASA Pi Day challenge. In order to solve the four problems, users must use the formula pi. The first challenge asks how many times the Mars rover Opportunity’s wheels might go around. Challenge number two asks the amount of images the Dawn spaceship will take as it takes pictures of Ceres the dwarf planet. Number three asks how much the possible amount of liquid the moon Europa’s ocean has, and number four asks how much is the fraction of the radio beams are that will get to Earth from the spacecraft that is furthest away from Earth.
Pi is common, but it isn’t a simple process to find it. It is calculated by dividing two integers and is considered to be an irrational number. It goes on forever and so it is impossible to truly list the entire fraction that equals Pi.
For instance, if you wished to figure out the challenge regarding the amount of hydrogen produced in an area of Europa, then you would have to divide the amount of surface area there, and that is the area of a sphere that has a radius of 970 miles or 1,561 kilometers, to get the answer.
Another interesting thing about this special date is that at precisely 3/14/15 at 9:26:53 a.m., it is literally the most perfectly “pi” time of the century. Make sure to note when the date and time spell out the first 10 digits of pi: 3.141592653. So grab a slice of your favorite pie, and celebrate math!
A second Pi Day challenge is meant for school kids in grade four to grade 11, but anyone is allowed to take a chance at answering them by going to www.jpl.nasa.gov/edu/piday2015. Teachers of students attempting the challenge can also download some infographics and a PDF with several handouts to use with their students.
