New Bright Lines on Mercury Indicate Geological Activity

The smallest planet in our Solar System, Mercury, may have an important secret. Bright streaks on its surface could show that recent geological activity is happening. This is surprising because scientists once thought Mercury was inactive.

A new study by astronomer Valentin Bickel and his team from Germany and Italy shows 402 of these bright lines, called lineae. Mercury’s surface is not as dull as once believed. Instead, it appears to be more active than expected for a planet that has cooled for 4.5 billion years.

The researchers used advanced computer methods to look at 100,000 images taken between 2011 and 2015. They found that most bright lines appear on the sunny sides of craters, suggesting they are still forming. The streaks may show that heat and materials, like sulfur, rise from inside Mercury.

Bickel explained that these streaks could come from deeper layers of the planet through cracks made by impacts. The team plans to gather more images from upcoming missions by the European Space Agency (ESA) and Japan Aerospace Exploration Agency (JAXA) to support their findings.