From an early age, Katherine G. Johnson loved doing mathematics. She would count everything. She loved to figure things out. She always asked questions.

She was born Aug. 26, 1918 in White Sulphur Springs, W.Va. Katherine's parents decided to move the family to Institute, W.Va., where Katherine and her siblings could finish high school. She graduated from high school at age 14 and received her Bachelor of Science degree in French and mathematics from West Virginia State College (now West Virginia State University) when she was 18. Later, she attended West Virginia University, where she was one of the first African Americans to enroll in the mathematics program.

After working as a teacher for several years in Virginia and West Virginia and raising a family, Katherine was hired at Langley Research Center in Hampton, Va. in 1953. In these early days, females were often called "computers." They would do the calculations for the various aeronautics experiments and projects. Their work was thorough and meticulous. Usually they were not allowed to assist with the all-male flight research teams.

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One day, Katherine and a colleague were assigned to assist one of these all-male teams, and Katherine's knowledge of analytic geometry was impressive to the all-male bosses. Katherine remained to assist with her knowledge of geometry and various branches of mathematics useful to the Langley Research Center. Eventually, while working at NASA, she calculated the trajectory (or flight path) for the space flight of Alan Shepard, who was the first American in space.

Katherine continued to work at NASA for 33 years. During this time, she calculated the trajectory for the Apollo 11 flight to the moon and later worked with several NASA programs, including the Space Shuttle program.

During Women's History Month, we celebrate Katherine, who overcame female and racial stereotypes. Her advice: "Roll up your sleeves and practice" and "keep trying." This is good advice for everyone.

In November, Katherine received the United States' highest civilian honor, the Presidential Medal of Freedom. The young girl who loved math, asked questions, and never gave up is now recognized as an American hero.

PI DAY ACTIVITY

If you like math activities like Katherine did, try the one below. As it turns out, March also is the month for Pi Day.

Pi is a "constant" (always has the same value) number frequently used in mathematics, science and engineering. Pi represents the ratio of the length of the circumference (all the way around) a circle divided by the circle's diameter (the length of a straight line from one side of a circle to the other through the center). Pi is called an "irrational" number, a number that never ends in any repeating pattern no matter how many decimals you take it out to.

Finding Pi

See if you can find Pi for yourself, all you need is:

1) A trash can lid that is round (not bent)

2) A spool of thread

3) A tape measure (metric is easier to use) with mm marks

4) A calculator

5) Paper, pen and an assistant

Procedure

1) Tie a small knot at the end of the thread - this is your zero mark.

2) Carefully wrap the thread around the outside of the trash can lid - this is the circumference.

3) Use the tape measure to find the length of the thread (circumference).

4) Write this down, and do this nine more times for a total of 10 trials.

5) Add up the 10 circumferences - circle this answer.

6) Carefully use the thread to find the diameter of the trash can lid - one side to the other across the center of the trash can lid.

7) Use the tape measure to find the length of the thread (diameter).

8) Write this down, and do this nine more times for a total of 10 trials.

9) Add up the 10 diameters - circle this answer.

10) Now, divide the circled Circumference answer by the circled Diameter answer.

This is your estimation of Pi.

If your procedure for finding Pi was carefully done, your Pi should be close to the accepted value of 3.14159. If your answer is a little off, check your procedure and redo the measurements. Anything close to 3.14 is very good.