The Restaurant at the End of the Universe

What will be in astronauts' lunch boxes when they go to Mars? Soggy sandwiches, squishy bananas and crisps are unlikely to make the cut.

‘If we go to Mars, that’s a two and a half year mission, so the food would need a five year shelf life,’ explains Dr Michele Perchonok, a food scientist at NASA’s Johnson Space Center in Houston.

There is no refrigeration on board spaceships, so harmful bacteria will have to be zapped before take-off using high pressure processing or microwave sterilisation. ‘With these emerging preservation technologies, foods have a much higher quality once they’ve been processed. And with higher quality comes higher nutrition,’ adds Perchonok.

Saving space is another major consideration. Visitors to Mars will need to pack light and keeping the contents of the food cupboard down to a minimum is key. ‘We want to make things as compact as possible and as lightweight as possible,’ says Perchonok. An even bigger challenge however is ensuring that the food tastes good.

Staying down to Earth

Space travel may summon up thoughts of strange, futuristic food stuffs, but Perchonok’s team strive to ensure that astronauts’ meals taste like they would back on Earth. ‘As missions have got longer and longer, we’ve started developing foods that are closer to home,’ says Perchonok. So astronauts are more likely to be slurping up spaghetti than downing weird space shakes.

Serving food in zero gravity can still hold a few surprises. ‘The crew get to try the food before departing, but we do receive reports that once in orbit it doesn’t taste the same as on Earth,’ comments Perchonok. ‘One reason is that you are in weightlessness and so hot air does not rise. About 85 to 90% of what you taste is really what you smell so if you can’t smell these aromas you may not taste as much.’

Mars bars

As well as their pick of the standard menu items, homesick astronauts are allowed to bring a stash of their favourite Earth treats, as long as these can be stored and consumed safely. Unfortunately for some, this means no crisps or biscuits. ‘We can’t have any crumbs on board,’ says Perchonok. ‘Crumbs can not only go into the equipment and clog up filters but could also get into your nose or your eyes.’

Despite crisp deprivation, today’s astronauts should still consider themselves lucky compared to their predecessors, who endured sandwiches compressed into bite sized cubes and pureed dishes similar to baby food. ‘Now astronauts have around 160 to 180 unique items which they can choose from,’ says Perchonok.

In coming decades, space crew could be treated to the ultimate luxury on Mars – fresh food. Researchers believe that crops such as mizuna lettuce, wheat or soy beans could be grown on Mars. And who knows, if we do find alien life on Mars, it might even be quite tasty.

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