A spacecraft carrying European and Japanese probes passed closer to Mercury than originally planned overnight after thruster problems delayed the mission to study the little-known, sun-scorched planet.

The new path meant the spacecraft needed to fly 35 kilometers (22 miles) closer to the planet than initially planned—passing just 165 kilometers above the surface—during its latest flyby.

The European Space Agency's operations team confirmed that "all went well" with the flyby overnight. It also posted a new image taken by the probe of the planet, whose pockmarked surface resembles the moon.

Mercury is by far the least studied of the four rocky, innermost planets in our solar system, which also include Venus, Earth and Mars.