When Buzz Aldrin and Neil Armstrong walked on the surface of the moon 50 years in the past, they took pictures, collected lunar rock samples and left behind an experiment that is still sending back information.
Aldrin positioned an array — an arrangement of 100 quartz glass prisms in rows — on the surface. Later, the Apollo 14 and 15 missions would also add similar arrays to the surface.
The simple experiment would not require any power, which is why it is still serving a purpose.
The arrays reflect light, which is filled with valuable perception, back in the direction of Earth. Observatories in Italy, France, Germany, and New Mexico regularly aim lasers on the arrays and notice the time it needs for the light to return to Earth, based on NASA.
Scientists can measure that distance down to a few millimeters. This permits researchers to find out the moon’s orbit, rotation and its present orientation, which might be needed to land on the moon. Additionally, they act like mile markers for the cameras connected to spacecraft.
Though we all know that the moon is about 239,000 miles away, the arrays allowed scientists to find out that this distance really will increase by an inch and a half annually.
Previously it was believed that the moon had a solid core. However, information from the arrays has revealed that the core is fluid. This core determines the path of the lunar poles, which the array information may also help decide through orientation.