"There is a silver lining. Due to the fact that the Spirit is immobilized, we can use its radio signal to calculate its motion in space" - said principal investigator Steve Squires (Steve Squyres).
Mars rotates on its axis and around the sun. Since the rover is stationary, then the coordinates of the transmitter will be changed in accordance with the movement of Mars’ orbit. Scientists already know the coordinates of the movement of the red planet around the sun, so the data transmitter will be useful in clarifying that as the planet rotates around its own axis.
"Mars varies (through a cycle of precession) during the rotation," - said Beynerdt Bruce (Bruce Banerdt) of the Laboratory of NASA - "We measure these variations, using the Doppler effect (allows you to measure the change in position of the receiver or source), taking radio Spirit ’a’
"Mars makes a complete cycle of precession for 170 million years," he added. "Therefore, we will measure very small movements - fixing the slightest change. But these small numbers of a lot of talk about the core of Mars."
First of all, it will help to determine whether the core is liquid or solid. There is evidence to suggest that it was melted in the distant past. The molten core is composed of a liquid that moves and is a conductor of electricity, forming a powerful magnetic field. Researchers are still discovering the remains of the field, but are not sure how much of the core is molten at the present time (if at all anything is melted).
If the hard core of Mars, the nature of the oscillations will be significantly different from the oscillations of the liquid core, "- said Squires.
Try to spin the hard-boiled egg - and compare it with a spinning raw egg. The difference between the nature of the rotation will be noticeable to the naked eye.
Spirit’s radio signals will also help to determine the exact speed of the oscillations of Mars. This, in turn, will help to calculate the moment of inertia of Mars.
The moment of inertia of a rotating object, in this case the planet - a number that describes how easy or how difficult it can be to change the rotation. "The moment of inertia affects the speed with which varies axis of Mars, so the speed of oscillation, can indirectly determine the moment of inertia," - said Beynerdt.
This will provide data on the moment of inertia, in addition to other known data about Mars - its size and weight. "Combining these three values with our understanding of how iron and rock behave inside a planet, we can calculate the size and density of the core of Mars. And the density tell us what elements in a mixture with iron at the core."
"This study will replenish body of knowledge about the formation of the solar system and its planets. Spirit’u must pay tribute, he never ceases to find all the new application."
But first, the rover will experience a long, hard winter. The great baseball player Rogers Hornsby (Rogers Hornsby) once said: "People ask me what I do in winter when there’s no baseball. I’ll tell you what I do. I look out the window and wait for spring." Just tell us interesting news in detail.
Original: Science NASA