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Making Babies In Space May Not Be Easy
Hugh Pickens writes "Studies of reproduction in space have previously been carried out with sea urchins, fish, amphibians and birds, but Brandon Keim writes in Wired that Japanese biologists have discovered that although mammalian fertilization may take place normally in space, as mouse embryos develop in microgravity their cells have trouble dividing and maturing. The researchers artificially fertilized mouse eggs with sperm that had been stored inside a three-dimensional clinostat, a machine that mimics weightlessness by rotating objects in such a way that the effects of gravity are spread in every direction. Some embryos were ultimately implanted in female mice and survived to a healthy birth, but at lower numbers than a regular-gravity control group. Part of the difference could be the result of performing tricky procedures on sensitive cells, but the researchers suspect they also reflect the effect of a low-gravity environment on cellular processes that evolved for Earth-specific physics. '"These results suggest for the first time that fertilization can occur normally under G environment in a mammal, but normal preimplantation embryo development might require 1G," concludes the report. "Sustaining life beyond Earth either on space stations or on other planets will require a clear understanding of how the space environment affects key phases of mammalian reproduction."'"
So don't do that.
Using acceleration to counteract undesirable effects of microgravity appears to be a universally ignored solution. It's like people are so amazed by how awesome zero-g is that they can't accept that working against it might be the best option.
problem: humans lose bone mass in zero-g
brain dead solution: we need to change humans with drugs! oh, and we'll make them exercise more too.
problem: embryos don't develop normally in zero-g
brain dead solution: we need to study embryonic development more, and hey, maybe we can find some drugs to fix it!
problem: transferring cryogenic propellant in zero-g is hard
brain dead solution: we need to learn more about fluid dynamics in zero-g!
Back in the Gemini days they actually bothered to join a pair of spacecraft together and spin them up. The effect was about 1000th of a g, but it was a successful mission. Everyone presumed that NASA would continue this research after Apollo, with longer tethers and slower rotation, a 1g environment could be created. That didn't happen. Instead, the fixed module concept took over and "studying the effects of zero-g" became the mantra. No matter, the Japanese space program proposed a module that would allow the study of incremental gravity on mammals, everything from low gravity to three times earth gravity, or the astronauts could sleep in it. That was scrubbed.
Meanwhile, private industry is solving the problem of propellant transfer.
How we know is more important than what we know.
Problem (Kinda) solved ^_^
http://en.wikipedia.org/wiki/2suit
Also, the issue of reproduction in microgravity is old news, though TFA may just be adding tangible evidence to a theorized issue.
http://en.wikipedia.org/wiki/Sex_in_space
Indoctrinate : to instruct especially in fundamentals or rudiments Educate : to develop mentally, morally, or aestheti
These types of questions could be answered by comparing micro-gravity to artifial gravity. Unfortunately, the ISS module designed to do just that was cancelled
...Larry Niven predicted this years ago.
In his Known Space universe, the true separation of space-based ("Belter") culture from Earth-based ("Flatlander") culture occurred when the Belters completed their massive 'terraforming' of the inside of an asteroid named Sanctuary as a shelter and home for pregnant Belter women. Rotating the asteroid up to 1-g, they eliminated their last unwanted ties to Earth as women no longer needed to return to the home planet for the period of gestation and birth.
Though, if I remember correctly, Larry Niven's justification for the need was a bit different, as he reasoned that a human fetus brought to term in very low gravity would grow to a size that endangered the life of the mother... I think.
>> Standing on head makes smile of frown, but rest of face also upside down.
You are saying having a G-force spread in all directions is harmful in a way that zero-G wouldn't be. That makes sense for chicken-eggs in gently rotating glass blenders, but not for the embryonic cells within gently rotating chicken-eggs:
Imagine you're at the center of a giant plastic ball full of water. You have to tell whether or not you're in zero-G.
If the ball was sitting on the surface of the earth you might sink or float to the top, and you'd know right away you're not in zero-G.
Now imagine the ball is being rotated so that you don't sink in any direction (or you sink equally in every direction, if you prefer). As long as the fluid you're in is viscous enough and you are around the same density you couldn't tell whether you were in orbit or on earth.
Of course if you had a handful of uranium pellets you could drop them and they'd fall straight through the water; it only works as a decent zero-G analogue if everything inside was of the same density and/or the liquid is viscous enough to slow the fall in any direction.
On the scale of an embryonic cell there are no uranium pellets, the DNA in your cells isn't lying on the "floor" of the cell after all, and because on a microscopic scale water would seem a lot "thicker" it'd be like falling through syrup for a cell's organic molecules.
If the direction of gravity is changing fast enough from gentle rotation it'd be hard for the cell to "know" whether it was in zero-G or not.
tl;dr: If it's either you or the team of scientists who have had a "logic fail" it's probably going to be you..
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Human pregnancy is different from mice pregnancy. As pregnant woman stands up, gravity aids by pushing baby downwards. This has vital role readying mother for upcoming birth.
If you are outside the atmosphere, and not accelerating then you're basically in free fall.
Err no. If you are in freefall then you ARE accelerating be the very definition of what freefall means. If you let go of a ball it will accelerate downwards and it is in freefall. Freefall means that you are free to fall i.e. that only force acting on you is gravity and so the force of gravity will cause you to accelerate.
Sure, gravity is pulling you somewhere, but it doesn't really have an effect on anything inside the spacecraft (your reference frame is moving with you).
Hang on a minute. How can you possibly say that gravity is pulling you somewhere and at the same time claim that it is not affecting anything inside the spacecraft? What do you think is causing things inside the spacecraft to accelerate then? By definition your reference frame is ALWAYS moving with you even if when your surroundings are not. What gravity does is make this an accelerating reference frame instead of an inertial reference frame and the two are most definitely NOT the same.The equivalence between gravity and acceleration is one of the core concepts of GR.
From a biological perspective there is no discernible effect due to gravity.
Yes there is. The reason that your organism is accelerating towards the centre of the planet is an easily measurable effect. In both the case of freefall and sitting on the surface of the planet there are discernable effects due to gravity. In the first case you are accelerating and in the second case you are not accelerating because there is a reaction force between you and the surface of the planet equal and opposite to your weight. In the latter case your internal structure must transmit this normal force throughout your body to cancel your weight in order to prevent all parts of you from accelerating but in both cases the force of gravity acts on all parts of you to the same degree (assuming the same field strength).
This is the same as taking a lift. When the lift accelerates down it does not mean that gravity has suddenly become less it just means that your body has a reduced normal force to distribute because you have a small, downwards acceleration.
"The researchers are probably pretty smart people," and "forces may cumulatively add up to zero"
No matter how smart they are, they have proved they have a flaw in their logic. Cumulative Force isn't the same thing as Peak Force.
They are applying motion to the samples so its no wonder the samples are reacting differently to motion than being stationary in gravity. Which is also different again from being in zero G.
The peak differences are an important factor. For example no one would question it would affect or even damage the samples if we were to say, for example heat the samples to +100C above what they should be and -100C below what they should be. So even though it could be said on average they were at the temperature they should be, its very obvious the peak differences are also important not *just* the average. Same goes for gravity applied to the samples.
It really gets to me, the number of articles we see where some effect is used to mimic something else in an attempt to create a simulation, yet they assume all their results must be accurate. Why do they fail so often to question the limits of their simulation. It should be drummed into their heads, its a simulation and simulations have limits to what they can simulate.
There are 10 kinds of people in the world... those who understand binary and those who don't.
They carried out reproduction in space of sea urchins, fish, amphibians and birds, but no mice? If I were to study the effects of microgravity on pregnancy, I would put something similar to humans (at least a mammal) at the top of my list, instead of first trying a whole list of species that don't really resemble us. Why use centifuges to "simulate" zero G (?!) and not just send a few mice up to the ISS? OK, it might be difficult to get them to actually reproduce, maybe put them on a 1G centrifuge for the actual copulation bit and then let them float again.
It's worse than that. In regular gravity, any fluid left over will go to the floor. Where will it go in freefall? Essentially everywhere. Be it your clothes, your hair, electronics ...
It's probably a bit more serious than it is fun.
Also - imagine what happens if someone sneezes. Apart from the jet effect, you now have a huge spray of mist that'll continue until it hits something.