Data from NASA's Mercury Surface, Space Environment, Geochemistry and Ranging (MESSENGER) give scientists an idea on how to mathematically calculate Mercury's crust, which is actually thinner and denser than previously thought.
After the mission ended in 2015, researchers estimated that Mercury's crust is roughly 22 miles, but a scientist at the University of Arizona thinks the measurement is inaccurate.
Michael Sori, an associate staff scientist at the Lunar and Planetary Lab, calculated that Mercury's crust is only 16 miles thick, thinner than the previous estimation of 22 miles and is also denser than aluminum.
His study titled "A Thin, Dense Crust for Mercury" will be published in the May 1 edition of Planetary Science Letters.
Measuring Mercury's Crust
Using data from the MESSENGER, Sori adopted a mathematical formula developed by Isamu Matsuyama, an assistant professor at the Lunar and Planetary Lab. He then concluded that Mercury's crust is 25 percent thinner than the initial calculations.
"We know what minerals usually form rocks, and we know what elements each of these minerals contain. We can intelligently divide all the chemical abundances into a list of minerals," Sori said. "We know the densities of each of these minerals. We add them all up, and we get a map of density."
This latest finding supports the theory that Mercury's crust is formed largely due to volcanic activities. Scientists are puzzled knowing that Mercury's core is bigger than the size of its mantle and crust, measuring about 60 percent of the planet's entire volume.
Although there is still no universally accepted theory, Sori said the thinness of Mercury's crust could have been due to gigantic impacts that stripped away most of the rock formations. He added it is also possible that the sun's solar winds blew a major portion of the crust over time, thus leaving Mercury with a larger core.
Sori explained that by measuring Mercury's crust, they have more opportunities to study how the planet evolved to its current structure.
Arrival To Mercury
The European Space Agency, in conjunction with Japan Aerospace Exploration Agency, has received a go signal to proceed with its launching activities. The BepiColombo mission is scheduled to launch this year, where the ESA attempts to arrive on the least explored planet by late 2025.
The mission involves two spacecraft: the Mercury Planetary Orbiter and the Mercury Magnetospheric Orbiter — both of which will endure more than 350 degrees Celsius of temperature.
"It's been a long and occasionally bumpy road to this point, and there is still plenty to do until we are ready for launch," said Ulrich Reininghaus, ESA's BepiColombo project manager. "But we are extremely pleased to finally move our preparations to the launch site, and are grateful to everyone who has made this possible."
The launch window is scheduled from Oct. 5 until Nov. 29.
