Mercury appears to be less mountainous than the Moon and Mars

According to an article published in the journal Science, Mercury appears to be less mountainous than the Moon and Mars and the bowels of the planet from the Sun, with deep reserves of iron sulfide, are very different from the others in our system. The publication includes two studies from the information sent by the spacecraft "Messenger" a year ago became the first artificial satellite of Mercury and has been making observations of the topography and gravitational field in the northern hemisphere . 

The 485 kg probe was launched into space by a Delta II rocket in August 2004, and after three passages in the vicinity of the planet from the Sun, March 18, 2011 was placed in a highly elliptical orbit ranging from 200 kilometers to 15,000 kilometers of Mercury's surface. 

Technicians from the U.S. space agency NASA chose that orbit to protect the appliance from the heat radiating surface of Mercury. Only a small part of the orbit passes with the device attached to the heat of the hot side of the planet. 

One instrument that carries the capsule robot is a laser altimeter has been doing a study of surface relief in the northern hemisphere of Mercury, where it was found that the number of lifts is far lower than on the Moon or Mars. 

The team led by Maria T. Huber, Department of Earth Science, Atmospheric, and Planetary at the Massachusetts Institute of Technology, has used the altimeter which cover areas of 15 meters to 100 in diameter, and a distance of 400 meters between them in the regions under the orbit. 

"The radial accuracy of individual measurements is more than one meter accuracy with respect to the center of mass of Mercury is less than 20 meters," said the article in which scientists collaborated U.S., Canada and Germany. 

According to investigators, the most prominent feature in the northern half of Mercury is an extensive lowland region including a volcanic plain. 

Zuber and his colleagues were also able to examine the Calories crater, 1,500 kilometers in diameter, caused by an impact and determined that a portion of the crater floor is now higher than the crater rim. 

Meanwhile, another team led by David Smith, and which is also part Huber, used the radio tracking of the capsule Messenger to determine the planet's gravity field and the data inferred that Mercury's crust is thicker at low latitudes and thinner towards the north polar region. 

These findings give an understanding of the planet's interior, indicating that the outer layer of Mercury is denser than scientists believed until now. 

"The internal structure of a planet preserves substantial information about the processes that have influenced the thermal and tectonic evolution," says the article. 

He adds that "the measurement of the gravitational field of a planet provides essential information for understanding the internal mass distribution of the body." 

During the first weeks after the Messenger will be placed in orbit, the spacecraft was tracked almost constantly by the X-band stations (8 gigahertz) of the Deep Space Network of NASA, and after this period the coverage has been less frequent. 

The researchers explain that processed the data collected from 18 March to 23 August 2011 and measured gravity anomalies caused by mercury in the northern hemisphere. 

To their surprise, scientists found that the evidence points to a high density mass in the upper mantles of Mercury, although the presence of low iron in the surface rocks. 

"Therefore, there must be a deep reservoir of high density material that explains the high density of the solid mantle and the moment of inertia," the article concluded that the most likely composition of the reserve is iron sulfide.