ExoMars rover launch
ESA's Rosalind Franklin rover is planned to leave for Mars in October 2028. Its drill will reach two metres underground in search of molecules that ancient life might have left behind.
The story
Rosalind Franklin is the European Space Agency's first rover designed to drive on the surface of Mars. Its most important feature is a drill that can reach two metres underground. Every rover sent to Mars so far has only scratched or drilled into the surface or a few centimetres below it. This one is built to bring up soil and rock from much deeper and analyse it at once in a small laboratory inside the rover.
Depth matters because the surface of Mars is a harsh place for organic molecules. Mars has neither a thick atmosphere nor a magnetic field around the whole planet, so radiation from space reaches the ground directly. The soil also contains oxidising chemicals that break organic molecules apart. So finding nothing at the surface would not prove that life never existed there; it may only mean nobody has yet searched at a depth where traces could survive.
The planned landing site is Oxia Planum. Clay minerals, which form only in the presence of water, are widely exposed there, so it is thought to be a place where water stayed for a long time in the distant past. The rover will drill samples, place them in its onboard laboratory, and check whether organic molecules are present and, if so, what kind they are.
The road to launch has been rough. Launch was first planned for 2018, then 2020 and 2022, but failed parachute tests and the end of cooperation with Russia in 2022 caused one delay after another. Europe is now building its own landing platform to replace the Russian one, and NASA is providing the rocket and some equipment. The current target is launch in October 2028 and landing in November 2030, still a plan rather than a certainty.
Mission goals
The question of whether Mars ever had life has so far been approached mostly through indirect evidence. Dry riverbeds and deltas, layers of old lake sediment and minerals that form only in water have made it clear that Mars was wet for long periods. What remains unknown is what chemistry actually happened in that water.
Rosalind Franklin is aimed at that question. It brings up material from below the reach of radiation, without damaging it, and analyses which organic molecules are there and how they are shaped. Molecules made by living things and molecules made without life can differ in their proportions and in a left- or right-handed bias in their shapes, so this kind of data is the basis for any judgement.
For Europe the mission also carries technical weight. Entering the Martian atmosphere and landing is the step where missions fail most often. Europe tried with Beagle 2 in 2003 and the Schiaparelli lander in 2016, but neither achieved a working landing. Simply touching down safely and starting to drive would be a major achievement.
Mission chronology and background
The rover is named after the British scientist Rosalind Franklin. Her X-ray photographs provided key evidence that DNA has a double-helix shape. A scientist who helped reveal the structure of life's molecule on Earth now gives her name to a rover searching for the molecules of life on another planet.
ExoMars was planned in two stages from the start. The first, the Trace Gas Orbiter, reached Mars in 2016. It still works, measuring tiny amounts of gases in the atmosphere, and it is to relay the rover's data to Earth. The Schiaparelli landing demonstrator that travelled with it crashed into the surface, and lessons from that failure have gone into the design of the rover's landing system.
After launch the plan is a cruise of about two years and a landing in November 2030. The few minutes of entry and landing are the biggest hurdle, and only after a successful touchdown can the drill begin its work. China's Tianwen-3 sample-return mission is planned for around the same period, so the years around 2030 look set to be busy ones at Mars.
Where to see it — sky and simulator
The launch is something to watch on a live stream. Once the date is confirmed, ESA and NASA will announce the broadcast schedule. The trajectory can be followed in the orbit view. The route to Mars is not a straight line but part of an ellipse around the Sun, and a spacecraft can only set off when Earth and Mars are in the right positions. The orbit view shows the path leaving Earth, widening outward and meeting Mars months later.
In the real night sky, look for Mars itself. It appears as a bright point with an orange-red tint, and around opposition, when it is closest to Earth, it outshines the stars around it. When it moves to the far side of the Sun it fades noticeably. That change in brightness comes from the changing distance between the two planets, and it is the same reason chances to launch to Mars come round only about every 26 months.
FAQ
When will the ExoMars rover launch?
The target is launch in October 2028 and landing in November 2030. It has been delayed several times before, so the date is best treated as a target.
Why does the two-metre drill matter?
Radiation and oxidising chemicals make it hard for organic molecules to survive at the surface. Two metres down those effects are much weaker, so old traces may still be preserved there.
Is anything visible to the naked eye?
The spacecraft cannot be seen, but Mars is easy to spot as a bright orange-red point. The trajectory can be followed in the orbit view.
Why can missions leave for Mars only every two years or so?
Earth and Mars circle the Sun at different speeds, so the positions that allow a fuel-efficient trip come round about every 26 months. Missing one means waiting more than two years for the next.
Related
- Tianwen-3 — Mars sample return bid
- The 2028 Mars transfer window
- Perseverance launch
- Mars — object index
- Perseverance — object index
Times and figures are approximate — verify with official sources when planning travel. Simulation uses J2000 mean elements.