'Mercury' (Photo : Reuters)
NASA's Messenger probe was retired and deliberately crashed onto the surface of Mercury some few days ago, but not until it had transmitted about 100,000 photos of the smallest and nearest planet to the sun. And then, the probe also revealed that Mercury has a gravitational field, had been around for nearly 4 billion years, and has a molten, liquid core.
Before its retirement in April 2015, Messenger provided enough information to reveal that Mercury is the oldest planet in our Solar System, and a mapping of the planet's gravitational field shows this is not much different, although lesser to the magnetic field on Earth, Space has learned.
With information retrieved from the spacecraft, space scientists are able to determine that Mercury has a crust that is thicker in low latitudes and also thin at both poles, meaning that the planet has about 85% liquid or molten core in its radius - much bigger than that of Earth's. Furthermore, Messenger provided that liquid iron sulfide is huge in the inner crust of the planet, which is contrary to what scientists know of other terrestrial planets.
The scientists at NASA were able to also determine that elevation changes in Mercury are lesser to what obtains on the moon or in Mars; while concluding that the uplift observed in the volcanic plain of the northern latitude is its most noticeable topographic mark, leading to the stretch of plains seen on the planet.
While it remains to be fully explored, space scientists find Caloris as the largest impact basin on Mercury, and perhaps the largest crater that has had scientists fascinated for quite some time. Measuring about 1,500 km wide, researchers are of the mind that tectonic activities and topographic changes impacted the initial characteristics of Mercury.
The researchers at NASA published their findings on Mercury's gravitational field and molten, liquid core in the journal Science Express.
