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In case you missed it, Elon Musk and his private company SpaceX successfully launched the Falcon Heavy — and its bright red Tesla — this week.
It's the largest rocket to be launched since the Apollo years and was designed to carry humans into space, bringing the possibility of a manned mission to Mars ever closer.
So when we eventually make it to Mars, how will we sustain ourselves?
Remarkably, research has shown plants might be able to grow more-or-less naturally.
It's not as simple as Matt Damon made it look in the 2015 film The Martian (spoiler alert: he would have died) — but it's not impossible.
As part of an astrobiology course at Villanova University in Pennsylvania, Edward Guinan and his class replicated Martian gardening conditions and experimented with which crops might grow best.
The basics: soil, light, water
The soil on Mars was probed, tested and tasted by the Phoenix lander in 2008, after a nine-month journey to the Red Planet.
Fortunately, we have something very similar here on Earth: a basaltic or lava-type soil. A similar variant is even available in most garden centres in the United States, with a little more iron than the Martian soil.
As Mars is further from the sun than Earth, its surfaces gets around 60 per cent less sunlight than the surface of Earth.
This environment favouring shade-loving plants was simulated by Dr Guinan and his students by using a shade-painted greenhouse, which also allowed them to simulate the very dry atmosphere of Mars.
To counteract the dryness, and provide the other essential ingredient for growing plants — water — Dr Guinan said Martian gardeners would need to find and defrost frozen water.
The astrobiology students only had to turn a tap, but they found the plants did dry out easily.
The Mars atmosphere, mostly carbon dioxide, would suit plants very well.
What worked?
Lettuce thrived in the Martian-style soil — growing quickly and well.
"I had a mixture of seeds, black seeded simpson, red oak leaf, buttercrunch," Dr Guinan said.
"These germinated in three or four days and by one month in, we had a crop … and it was tasty. All of our products from last semester we ate."
However, Dr Guinan pointed out its limited nutritional value meant it might not be worth growing.
The students also managed to grow sweet potatoes, basil, onions, garlic, mint — and even kale.
"Kale was especially useful, because it's very nutritious," he said.
When Dr Guinan suggested growing dandelions, his students were less than enthusiastic.
But this surprisingly versatile plant would grow well on Mars.
"You can eat the leaves, you can eat the roots," Dr Guinan said.
"The students didn't think about it, but you can make wine from the flower."
There will, however, be some obstacles, if we ever make it to the Red Planet.
The surface of Mars, and also airborne dust, contains small amounts of perchlorates.
"Perchlorate salts on Earth are used in fireworks, explosives and in some fertilisers," Dr Guinan explains.
"Even in small amounts, perchlorates have been found to be very toxic to people, mainly affecting the thyroid gland and uptake of iodine as well possibly being carcinogenic."
In The Martian, astrobotanist Mark Watney, played by Matt Damon, successfully grew potatoes in a mix of Mars soil and rehydrated faeces.
It may come as shock (or, perhaps not…), but this Hollywood scene was not scientifically accurate, according to Dr Guinan.
"Mark Watney would have been exposed to possibly lethal amounts of perchlorates during his time on Mars and also from eating the potatoes grown in the untreated Martian soil," he said.
To survive, Watney would have had to remove the perchlorates by washing the salts away, or by using a certain bacteria that ingests chlorates releasing oxygen.
"But this was glossed over in the movie."
Martian brewers of the future
Perchorates aside, once the new inhabitants of Mars have enough food to sustain themselves, what else could make life there more liveable?
In Dr Guinan's classes, one student was fixated on growing hops. The whim was indulged, with surprising results.
"Hops grew very well, but it needs to grow up to three metres tall before they flower," he laughed.
The students didn't consider that barley was required for their interplanetary brewery cooperative.
But this will be remedied in the second go of this course. So, the race is on to open the first craft brewery on another planet.
It's a nice thought to know that a cold one could be a possibility at the end of the slightly longer Martian day, and made with some locally sourced hops.
Topics: space-exploration, planets-and-asteroids, astronomy-space, united-states
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