- Communications - at present they only communicate with Earth every 24 hours - the rovers might as well be at Pluto. Would make a big difference if we had, e.g. a few satellites on orbit around Mars that are just there to relay signals to Earth- and laser communication or some such for higher bandwidth also
- Speed - this is tied in with communications - if you could communicate more regularly, and using delayed real time - the rovers could drive over the surface more quickly and get more done. Opportunity took 10 years to travel a distance Lunakhod could travel in a few months
- Better sterilization. At present it's still a major challenge to sterilize the rovers for life detection. Viking 1 and 2 were sterilized using many hours of heat treatment - but that would destroy modern delicate electronics and alignment of sensitive instruments. There's a new method now, low vapour hydrogen peroxide sterilization which may fill the gap. In the future surely we will be sending rovers to investigate the Warm Seasonal Flows and the various other places on Mars where there may be liquid water and life - if so - they need to be sterilized to a higher standard than Curiosity - similarly to Viking to make sure that we don't introduce Earth life to Mars - would be tragic to go there to search for life and only find the life you brought on your own rover.
- Life detection - for some reason NASA hasn't sent any life detection equipment to Mars since Viking in the 1970s - not capable of detecting present or past life in the low concentrations expected on Mars. The instruments exist - but have never been sent. First opportunity to do this is with ExoMars in 2018. NASA have no plans to do it at all in upcoming missions, they are focused instead on a sample return - not likely to tell us much about biology when you don't know if there is life in the sample. Organics don't necessarily mean life at all since meteorites bring organics to Mars anyway
- Better methods of locomotion in the rough terrain - and autonomous driving. I think myself that whegs are promising, and wonder why NASA hasn't tried them yet. But to be fair, there are few opportunities to send rovers to Mars, every two years, and very expensive missions, so I suppose they prefer not to experiment too much. All the same - would be good if they did. Lots of other ideas for alternative ways to explore Mars that they could try out in the future, NASA, ESA, Russia, or who knows, maybe India or Japan, or the Arab State Emirates, or one of the other countries.
Balloon rovers
Whegs
More ideas here: Soaring, Buzzing, Floating, Hopping, Crawling And Inflatable Mars Rovers - Suggestions For UAE Mars Lander
About the Author
Robert Walker
Writer of articles on Mars and Space issues - Software Developer of Tune Smithy, Bounce Metronome etc.Studied at Wolfson College, Oxford
Lives in Isle of Mull
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