Europe and Russia have delayed the launch of a Mars rover to July 2020. The rover, equipped with a drill to search for life in the subsurface, is the second prong in the ExoMars program. The first ExoMars mission, the Trace Gas Orbiter, launched this past March, and will attempt to nail down the existence and source of methane gas, which has mysteriously come and gone over the years.
But many scientists had looked ahead to the ExoMars rover as the main event, not only as a chance for a country other than the United States to successfully land a rover, but also as a mission that would explicitly be looking for life. The mission was originally intended to be a U.S. collaboration, but NASA backed out in 2012.
Russia stepped in the gap, pledging rockets to deliver the two missions to Mars, and also a landing system that would safely deliver the rover to the surface. In October 2015, the mission decided on the destination for the rover: Oxia Planum, a region with sinuous valleys and fan-shaped deposits that indicate ancient river channels and deltas. But scientists had faced problems in marrying the European-led rover to the Russian landing system, which will use aerobraking, parachutes, and reverse thrusters. The delay puts the ExoMars rover on a parallel track with NASA’s 2020 rover, which is expected to pick up rocks and cache them for eventual return to Earth. The estimated €1.2 billion cost of the ExoMars program is sure to rise with the delay, but officials did not disclose any new cost estimates.