According to a NASA Jet Propulsion Laboratory statement, ground controllers on Earth have elected to send the Curiosity rover on its way rather than drill into a potential target rock. Various targets for drilling are selected and then assessed as to whether they can be safely drilled without posing a danger to the rover itself. So far, Curiosity has successfully drilled into three targets that were able to pass that test.
However, a particular variety of rock dubbed “Bonanza King” and its setting proved too hazardous for the rover team to commit Curiosity to any further attempts at drilling. On August 20, during a test of the percussion drill, the flat rock shifted under the impact of the drill. Furthermore, Bonanza King is situated at the northeastern end of the so-called “Hidden Valley,” an area which proved more difficult to traverse than originally expected; Curiosity has slipped in the sand numerous times since it first began entering the valley in early August.
“After further analysis of the sand, Hidden Valley does not appear to be navigable with the desired degree of confidence,” explained JPL Curiosity Project Manager Jim Erickson. “We will use a route avoiding the worst of the sharp rocks as we drive slightly to the north of Hidden Valley.”
Instead of drilling into Bonanza King, Curiosity will resume its trek towards the lower slopes of Mars’ Mount Sharp in the center of Gale Crater. Since landing in the crater in August 2012, Curiosity has covered a distance of approximately 5.5 miles, with around two miles still to go before reaching Mount Sharp. Curiosity’s discoveries thus far include geological evidence of liquid water and habitats conducive to microbial life on the Martian surface in the planet’s distant past. The strata exposed around Mount Sharp should provide more clues to the tremendous environmental shifts that occurred on Mars.