Dr. james van allen and his group of united states scientists discovered a set of

  Radiation Belts.

Explanation:

  They were named Van Allen radiation belt in honor of him. The way they discovered it was by including scientific research instruments on space satellites.

  The Van Allen radiation belt is a group of energetic charged particles, the majority came from the solar wind and are captured and held around a planet by its magnetic field.

  I hope this answer helps you.

see the picture for the vector

the magnitude of the vector by pythagorean theorem

r = √( (-10)^2 + (3)^2 ) = √109

magnitude = √109 units

the direction angle between vector and x-axis is

tan^(-1)(3/10) = 16.699

so the direction is approximately 16.7 degrees north of west