Way, way back in the thread I made a guestimate of 200 plants. I don’t know how realistic that is.
Does that give “Grow Lights” [sup]TM[/sup] the unusual color?
Yeah.
You can’t do that with live potatoes.
The Hermes took two years to get to Mars…
And kept in a cool, dry environment, potatoes will in fact last that long. Mom’s kept potatoes for longer than that in her root cellar, and she didn’t even have to replace the atmosphere with nitrogen, or any of the other measures NASA could have taken.
It took only four months (124 days) for the Earth to Mars part of the flight.
I’m still dubious, as are these guys.
I think it would have been way more plausible to have some seeds on board for the Botanist to you, know, Botanize with.
beowulff’s not being very clear with his objections, so I can only speculate, but I suspect the concern is that the germinating cells (the “eyes”) of the potatoes shouldn’t have survived vacuum-packing and long-term travel, although not as long as his guess. Still, seed potatoes have been stored from harvest to spring planting as long as humanity has been cultivating potatoes, so long-term storage of potatoes which will sprout isn’t a problem. Dunno about vacuum-packing though.
What in your mind makes a potato grown from eye or cutting any less botanical than anything grown from seed? 
That’s just nonsense.
The article you point out to support your assertion has two glaring errors:
- “vacuum-sealed freeze-dried spuds”
Wrong, as far as I could tell. Vacuum-sealed, yes, but whole and fresh potatoes. “Freeze-dried”? Sorry. Totally missed that. So the potatoes are viable in that dimension, assuming the vacuum-sealing process isn’t lethal to the sprouting eyes.
- “Store bought eating potatoes may have been treated to prevent sprouting, thus minimizing any yield if you’re lucky enough to get any potatoes at all. (Sprout inhibitors are designed to increase the shelf life of the potatoes.)”
As if. The potatoes I buy, from J. Random Grocery Store, sprout just fine if I don’t use them fast enough. Even the article itself uses “may have been”. Which is to say, “apparently weren’t”.
Feh. Useless clickbait.
Not pirates, mutineers. Pirates take other people’s ships. Mutineers take their own ship. My point was that if the quasi-governmental status of NASA leaves the ownership of the final vessel in the Government’s hands, there is a higher likelihood of prosecution - especially for the military folks. If it leaves final ownership in the commercial side of NASA, then no way are they going to press charges; this is confirmed, I think, by Chronos’s observation below.
So yeah, definitely a hint of pet-like sentimentality in the movie.
Nope. 124 days.
That much lighting is pretty implausible. Since our eyes and brains do such a good job perceiving dimly and brightly lit objects, it’s easy to forget that sunlight is orders of magnitude brighter than the artificial light we’re used to. Wiki gives typical home indoor lighting at 50 lux, bright office lighting at ~500 lux, and direct sunlight at ~50,000 lux, where 1 lux = 1 lumen/m^2. If we generously assume 200 lumens/W efficiency for LEDs (higher than most production LEDs) that gives us 250 W of LEDs for every square meter of the growing area. With a growing area of 62 m specified in the book, that totals up to a 16 kW array of LEDs.
That’s ~2000 ordinary household LED bulbs (at 8 W, 100 lumens/W).
Sure, that’s not impossible if The Martian was about, I dunno, rogue space pirate marijuana farmers, but it’s hard to imagine there being anywhere near that many spare light bulbs for the hab interior lighting.
If I wanted to fanwank this as much as I did the hydrazine production, I suppose we could have Watney repurpose a several kW-sized LED lights scrounged from external lighting sources. Maybe there were really bright landing lights on the remaining MAV stage, and several external lights on the Hab for working outside after dark? Plus headlights, with spares, from the rovers? And while were at it, stadium lighting for those games of Martian baseball that keep going after dark?
Or, maybe NASA overspecced the room lights in the Hab by a factor of 1000. Those babies are the same LEDs modules they use in streetlights - NASA wanted them wired in parallel so no matter what the lights keep working. And they are water cooled.
Not at all implausible…
Yes, but the lighting was just a supplement to the actual sun. And with Mars having such a thin atmosphere, and slightly longer days, I wouldn’t think they’d be receiving all that much less sunlight than on Earth. He was just trying to maximize production.
But could they actually get sunlight *inside *the hab?
Just a few hundred extra kg of lighting for the hell of it?
Total heat probably isn’t a problem, since I think the Hab relied on electric heating anyhow, though if you packed that many LED modules close together I imagine they’d get a lot hotter than they should…
I see movie the movie Hab had a translucent ceiling, and that was what I always imagined in the book since artificial lighting would be ludicrous. However, it looks like the only mention of lighting for the potatoes is the artificial lights quoted by standingwave.
Yeah, I click on these hoping to see an in-depth discussion of, I dunno, cation exchange capacity of the Martian soil, with or without lightweight amendments carried all the way from Earth, and that maybe potatoes can’t tolerate iron levels above a certain level. But I get “Nuh uh! Space potatoes wouldn’t sprout!”
TruCelt, “please take care of this rover” was in reference to the vehicle he traveled in, not the little Pathfinder bot.
The two years reference is how long Hermes would be in space altogether, after retrieving Watney, and returning to Earth.
Bummer. I thought that was so cute! :rolleyes:
Are lumen log or linear? I recall that two candle power is the brightness of ten candles, for example.