After four years orbiting the closest planet to our sun, the Messenger spacecraft will this make a death-dive into Mercury. But the probe hasn’t finished its mission yet, with new images emerging of the planet in unrivaled detail. Now Nasa has released an images taken by the probe’s Visual and Infrared Spectrometer (Virs) revealing distinct features such as volcanic vents and fresh craters.
The spacecraft is expected to smash into the planet’s surface at 2.4 miles per second (3.9km/s) on Thursday 30 April at 3:30pm Eastern Time. However, when it does, Messenger will be behind Mercury, and hidden from Earth.
Among the features Messenger has revealed to scientists in the past month are patterns of distinctive hollows – each around a couple of hundred metres wide – in the bottom of a huge impact basin. It has also sent back detailed images of huge 1.2 mile (2km) high cliffs that cut across a crater named Duccio on the surface. Another image shows a 621 miles (1,000km) long cliff that rises 1.8 miles (3km) above the surface, called Enterprise Rupes.
Data sent back by Mercury suggests these cliffs, or lobate scarps as they are called, have formed as Mercury has cooled and contracted over time, creating dramatic tectonic faults on the surface. Another image shows a meteorite crater that has almost completely filled with lava on Mercury’s northern volcanic plains, leaving just the hint of a rim behind. It also shows how the contracting surface of the planet has also created strange formations where ridges and cliffs have hit other lava filled craters.
Andy Calloway, Messenger Mission operatoins manager at Johns Hopkins Applied Physics Laboratory, said: ‘The Messenger spacecraft operates in one of the most challenging and demanding space environments in our solar system.’ Launched in August 2004, Messenger has traveled more than 4.9 billion miles (7.9 billion kilometers) during its mission to Mercury. Its journey included 15 trips around the sun before it entered orbit around Mercury in 2011 – the first spacecraft to ever do so. During its mission is has acquired more than 250,000 images and collected more than 10 terabytes of data with its suite of seven instruments. It has also revealed Mercury’s complex internal structure and that the planet has an unusually large core that is still partially liquid.
By Richard Gray and Ellie Zolfagharifard For DAILY MAIL
27 April 2015