Seismic Investigations, Geodesy and Heat Transport, aka InSight, is NASA’s prodigious mission on planet Mars. It landed in November 2018, and now no less than six new studies were revealed. One of them approached the magnetic fields on Mars, and it can become the opening for future understanding of Mars’ formation and evolution.
The first observation is that the Martian magnetic field is ten times stronger than formerly believed. So far, with the help of satellite observation, magnetization could be studied only in small areas. With the help of Insight, the interior structure and upper atmosphere can be observed.
Measuring magnetic fields today can bring answers about Mars’ magnetosphere from billions of years ago. It looks like up until 4.2 billion years ago, and Mars had a different magnetic field. After the switch-off, Mars became a victim of solar winds that made the planet the dry world we know.
The InSight Mission Shed More Light On Mars’ Magnetic Field
The magnetic rocks that hold the magnetization from before the switch-of are hidden under Martian ground. From a couple of hundred feet to ten kilometers below. Scientists have high expectations from Insight. They hope it will help them identify which rocks are magnetized and how old they are.
So far, Insight also brought data about the influence that Mars has on the interplanetary magnetic field. Mars doesn’t have a magnetosphere, and that makes it more exposed to the solar winds that carry the Martian magnetic field into the interplanetary magnetic one.
Mars’ local magnetic field has an odd particularity. The way it varies. Earth’s magnetic field is not constant either. The strength of the field and the location of its poles vary. Moreover, the Earth’s poles periodically reverse their orientation in a process called geomagnetic reversal. The most recent reversal occurred 780,000 years ago.
Mars’ magnetic field fluctuates between day and night. And this is not all: around midnight, short pulsations occur. They last for just a few minutes, and scientists have no idea what could cause that. They speculate that it might also have something to do with the solar wind.