Have we been wrong about why Mars is red? | Hacker News Reader

Have we been wrong about why Mars is red?

esa.int

45 pointsrntn9 comments

The key point is that the rust that gives Mars its red color was thought to form in a dry period, after mars lost its water:

> Previous studies of the iron oxide component of the martian dust based on spacecraft observations alone did not find evidence of water contained within it. Researchers had therefore concluded that this particular type of iron oxide must be hematite, formed under dry surface conditions through reactions with the martian atmosphere over billions of years – after Mars’s early wet period.

The new research suggests otherwise:

> new analysis of spacecraft observations in combination with novel laboratory techniques shows that Mars’s red colour is better matched by iron oxides containing water, known as ferrihydrite. Ferrihydrite typically forms quickly in the presence of cool water

Ferrihydrite also produces water when heated. You'd need to collect and process 250-500kg of martian soil per day to produce enough water for one person to survive, assuming half of the iron oxide is actually ferrihydrite. You'd also need the energy to do the separation and heating.

Is that assuming the water expelled from the person can be reused or not?

Reasonably, not? With a sealed environment nearly all water could be reclaimed. But good callout that in practice such ore may be a feasible source of water for an expidition.

One interesting question is could bacteria have been involved. We have those producing a redish effect on earth https://en.wikipedia.org/wiki/Iron-oxidizing_bacteria

It's pretty much been shown that rocks could have been thrown from Earth to Mars and visa versa during meteorite strikes so they could have got around.

I hadn't realized there was a project to drill 2m holes into Mars and look for signs of life that was supposed to fly in 2022 but it was in cooperation with the Russians and all fell apart due to the war. https://en.wikipedia.org/wiki/Rosalind_Franklin_(rover)

I fail to imagine meteorite event that could throw rocks to stable orbit earth let alone go to the Mars.

I guess over eons everything is possible and didn’t do any math but my understanding of physics is saying „not possible”.

https://en.m.wikipedia.org/wiki/Martian_meteorite

While Earth represents a larger gravity well to escape I’d imagine given that Martian rocks have ended up on Earth that the opposite having happened is quite likely.

"Dinosaur asteroid 'sent life to Mars'" https://www.bbc.co.uk/news/science-environment-25201572

Estimates when the 180km-wide Chicxulub crater in Mexico was formed about about 70 billion kg of rock was thrown into space. Obviously you need a big bang to overcome the Earth's gravity.

Here's a NASA guy trying to simulate it in the lab https://youtu.be/bfrHoGlFLwk?t=70

cuz red rising lmaooo

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