I’ve always wondered why Mars had no magnetic field and this article seems to have solved the riddle.
www.universetoday.com
One day, Earth will also lose its magnetosphere but we have about a billion years to find a new home

We Might Know Why Mars Lost its Magnetic Field
A new study might answer one of Mars' most compelling mysteries: How did it lose its protective magnetic shield? It may have a strange core.

One day, Earth will also lose its magnetosphere but we have about a billion years to find a new home