In search of the center of masses of the Earth

2007/09/01 Elhuyar Zientzia Iturria: Elhuyar aldizkaria

• Geologia
• Astronomia

An effect of global warming on Earth is that polar ice is melting and that little by little the sea level is rising. It is calculated that every year it rises approximately two millimeters, but is the calculation correct? The answer will be possible thanks to a work done by a NASA geologist.

The work of the geologist has consisted in locating the center of masses of the Earth, in short, the level of the sea can be measured from the reference of this point. But the mass center of the Earth is not in a fixed place, but moves. So far, the LAGEOS satellite measures have been used to follow this movement, which emits a ray of light to the terrestrial surface and gathers what is reflected there. However, this method is dependent on tides and the atmosphere and does not provide great precision.

Therefore, the NASA geologist has combined the data supplied by the satellite with other methods that measure the exact position of the satellite itself. In this way, he has been able to calculate with great precision the position of the mass center of the Earth as if there were no sea or atmosphere.