Mercury topography released in stunning detail ahead of sun transit

9 May 2016

The topography of Mercury, the smallest planet in our solar system, has been revealed in stunning detail by NASA ahead of the planet’s transit of the sun today (9 May).

While many here on Earth will be turning their modified telescopes in the direction of the sun to catch a glimpse of a rare astronomical sighting of Mercury passing in front of it, NASA’s MESSENGER mission has managed to get a much closer look at the sun-baked planet.

Almost coinciding with today’s event, the US space agency has revealed that data gathered by its spacecraft has allowed it to generate the first global digital elevation model (DEM) of Mercury, which revealed in incredible detail the topography across the entire innermost planet.

This DEM will help future astronomers better understand Mercury’s rich geological history over the eons and pave the way for scientists to fully characterise Mercury’s geological history.

Piecing together 100,000 images of the planet’s surface, MESSENGER found some very interesting topographic features, including the planet’s highest point, which is revealed to be 4.48km above the surface, located just south of its equator in some of Mercury’s oldest terrain.

Meanwhile, the planet’s lowest elevation of 5.38km below its average surface height has been located as the floor of an area referred to as the Rachmaninoff basin, an intriguing double-ring impact basin suspected to host some of the most recent volcanic deposits on the planet.

10TB of scientific data

This data release marks the 15th, and last, of the mission, which has generated more than 10TB of scientific data on the small planet, including 300,000 images of its surface.

These new images of Mercury also include our greatest look at the planet’s north pole to-date as, until now, the sun’s position beside the planet has meant that its casting of a long shadow often obscured the colour characteristics of the rocks.

Now, with the help of five different colour filters, NASA has been able to reveal its northern volcanic plains in marvellous detail.

Speaking of the new images, Susan Ensor, a software engineer at The Johns Hopkins University Applied Physics Laboratory (APL), said:  “The wealth of these data, greatly enhanced by the extension of MESSENGER’s primary one-year mission to more than four years, has already enabled and will continue to enable exciting scientific discoveries about Mercury for decades to come.”

Mercury craters

A view of Mercury’s northern volcanic plains. Image via NASA/JHUAPL/Carnegie Institution of Washington

Mercury image via Shutterstock

Colm Gorey was a senior journalist with Silicon Republic