It’s fair to say that if you want to be a space scientist, you’d better learn to be patient. Because aside from the endless years of planning and construction, delays are often fairly common.

And, well, that’s exactly what’s happened to Europe and Russia’s next Mars mission. Their ExoMars rover, due to launch in 2018, has now been pushed back to 2020, due to technical and funding issues during development of the rover.

“Having assessed the possible ways to ensure successful mission implementation… a launch in 2020 would be the best solution,” the European Space Agency (ESA) said in a statement. The specifics of the delay aren’t entirely clear, although funding and development issues seem to be the problem, with ESA and the Russian Space Agency (Roscosmos) referring to “delays in European and Russian industrial activities and deliveries of the scientific payload.”

This rover, which was initially supposed to launch in 2011, will be the second part of the overall ExoMars project. The first part, which includes an orbiting spacecraft to study the atmosphere of Mars and a demonstration lander to practice landing on Mars, launched earlier this year and will arrive in October.

But the rover, which will perform one of the most extensive searches for life on Mars to date, is arguably the most anticipated part of the mission, so its delay is no doubt a blow to the various scientists involved.

^{Wish you were here? NASA, J. Bell (Cornell U.) and M. Wolff (SSI)} 

When the rover does get there, though, it’s going to be pretty impressive. It will use a drill to delve up to 2 meters (6.5 feet) below the surface, with a suite of other instruments helping scientists work out if Mars once hosted life – or still does today.

The reason for the two-year delay is that launches to Mars must occur in 26-month windows, when the planets are aligned to allow for a relatively shorter journey between them. Thus, after the slip from 2018, the next opportunity to launch is in July 2020.

If you’re yearning for a new Mars mission sooner though, don’t fret. In 2018, NASA will launch its InSight lander, itself also delayed by two years, which will also drill into the surface. And there’s the small matter of SpaceX’s unmanned Dragon mission in 2018, details of which are few and far between at the moment.

As for ExoMars, though, we’ll have to wait just a little bit longer to see the fruits of this exciting mission.