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Scientists Levitate Mice for NASA
sterlingda writes to tell us that scientists have built a mouse-levitating superconducting magnet, working on behalf of NASA to study variable levels of gravity. The group hopes to ascertain what physiological impacts prolonged exposure to microgravity might have. "Repeated levitation tests showed the mice, even when not sedated, could quickly acclimate to levitation inside the cage. After three or four hours, the mice acted normally, including eating and drinking. The strong magnetic fields did not seem to have any negative impacts on the mice in the short term, and past studies have shown that rats did not suffer from adverse effects after 10 weeks of strong, non-levitating magnetic fields."
are some of them north-oriented and some south?
can you make a compass out of them?
if you put one of those mickeys near a HDD, does it erase some of the data?
and finally, where do you find ferrous-enriched cheese to feed them?
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"It is now safe to switch off your computer."
Look for The Flying DutchFrog to see electromagnet experiments in levitation on other vertebrates.
Damn_registrars has no butt-hole. Damn_registrars has no use for a butt-hole.
From one of the earlier experiments.
Looks more like a cheese shredder than a large, scientifically purposed apparatus.
...using a 3-man slingshot and dead squirrels.
The dead squirrels did not seem to suffer adverse effects while they were levitating, though it must be said they were in this state only for a few moments and there were adverse effects after they struck their respective targets.
This comment does not necessarily represent the views and opinions of the author.
Why no video?
Flying mice on youtube would bring more media coverage of this.
What happens when you create a quantum superposition of levitating mice?
No, it works on the water in the animal. Red blood cells aren't ferromagnetic; all the iron is in haemoglobin, not little metallic bits.
# cat
Damn, my RAM is full of llamas.
Here's your pic.
Cell phones operate at different frequencies and different power levels than the apparatus used in this experiment, so the lack of adverse effects on the mice does not really say anything about the effects of a cell phone on mice (or humans).
Just because you are paranoid does not mean that no-one is out to get you.
I was going to mod you down, then I decided to respond instead.
Slashdot has always been behind the "news" cycle.
This is fine. Most people don't come here for breaking news, they come here for (sometimes) informative, enlightened, or humorous discussion of the article and related topics.
I'll just add that your griping is none of those things. If what you care about is being the first to read about something, then please feel free to go elsewhere. And feel free to not bother with the discussion on Slashdot when the same item is up a day or two later... you won't be missed if what you post is similar to the post I'm responding to.
Oh, and one last thing... Slashdot is a news aggregator. There is very, very little original content in the items posted to the main page. However, it is a community-driven site. If you're unhappy that items come through later here than elsewhere, one thing YOU can do to improve it is to submit articles yourself in a timely manner.
"Trolls they were, but filled with the evil will of their master: a fell race..." -- J.R.R. Tolkien on Olog-hai
That isn't how it works. The same fieild intensity that levitates a mouse would levitate a person. However, the volume throughout which the field is of constant intensity would have to be scaled up and the energy stored in the field is proportional to volume so your number may not be too far off if seen as a measure of the size and cost of the magnet.
Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
> It seems that these days, slashdot takes all of its news from gizmodo, wired,
> and ars.
And therefor I miss nothing important by not reading those sites while avoiding a great deal of crap.
Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
This is actually a discussion site, not a news site. We come here for the discourse and the surprisingly effective moderation system.
A slashdotter who didn't build his own computer is like a Jedi who didn't build his own lightsaber.
This was a static field. A static field is like resting your head on the floor. An oscillating field is like beating your head against the floor.
Of course, nothing will stop some people from claiming that strong static magnetic fields cause cancer. Maybe they can fight it out with the people who say that they cure disease.
That said, if you move a wire through it, you'll generate one hell of an electic field, but only while the strength of the magnetic field through the wire is changing.
Wait, if you move a wire through an unchanging field (perpendicularly), you'll induce a current, right? You'll also induce one if you hold a wire still in a field whose strength is changing.
On a related note, axons are in many ways like long wires. Move around in a high magnetic field, and you'll notice odd effects. It's more of a problem for people than for mice -- our axons run longer, and so inductive effects are stronger.
To be honest with you, when you reach this level of awesome in your experimentation, you don't even need a premise. The NASA scientists could have simply announced that they did it for the lulz and it would be okay.
I think the public would excuse it.
"Heeere I come to save the daaaayy.. Mighty Mouse is on his waaaay!!"
Flying mice. Sheesh.
they come here for (sometimes) informative, enlightened, or humorous discussion of the article and related topics.
I come here for the depressingly predictable jokes. Where's my "I for one..."? Ah, there it is.
Your favorite
From the other perspective, could this technology be used to add "gravity" (or a downward force equal to the Earth's gavity at the crust) in space? ...an alternative to centripetal force?
Oh, but they do get interesting, if you disable the rate-of-field-change safeties that are integrated into clinical scanners. Our lab does high-resolution MR imaging in small animals, and if we don't disable those safeties, we can't get the gradients we need. (In this field, "gradient" refers to a varying magnetic field that's overlaid on the nominally constant and uniform field from the main magnet.)
Even without involving the gradients, if you move your head too quickly near the bore of our 7T magnet, it can have very odd effects. I'm not sure of the mechanism, but I've assumed it has to do with currents induced in axons. They aren't wires, but they are conductive channels, and as Volta showed, they do respond to purely electrical stimulation.
(I hope someone better versed in MR physics will chime in here. I'm just a lowly computer guy, relying on what I've soaked up from my co-workers due to curiosity and overheard discussions.)
Wait? Wha? Highschool physics much? How was this post modded 5+ informative when it's so wrong?
With 16T, you can levitate an object of any size so long as it predominantly consists of water. It's not like a 1g frog will float, but a 2g frog will fall in the same magnetic field. The reason why the things floated are small is because its easier to make small magnetic fields. If you have a current going around a loop, and you double the radius of that loop, your peak magnetic field drops by a factor of 4. You do not need 150kT to levitate a human. You just need a magnet that is physically larger with the same field strength and geometry.
One more thing. It's not just the magnitude of the magnetic field that controls whether something will levitate or not. The key is that the magnetic field gets weaker as you move up. Wikipedia tells me that levitation power is proportional to B*dB/dZ. (the magnitude of the field times how quickly it diminishes as you move upward) That is to say, if you had a 150kT magnetic field, and it was constant everywhere, you wouldn't float in it.
Regarding gradients: The gradients used in MRI vary in *position*. Yes in time, as well, but only because they are pulsed. We can ignore ramping issues to first order. Since the field varies as a function of position, when you move around, indeed the flux is changing which can induce currents in looped conductors so as to oppose the change. This is called induction. Many people, my self included, notice a strange sensation when first entering an MRI magnet. This is because the field is only homogeneous over a relatively small volume, outside of which there are once again field gradients (these are different than the intentional field gradients used to obtain an MRI image). It is probably not axons but something in the ear that is picking this up, I am not sure. Also, field strength has *nothing* to do with this effect. It's how fast the field changes as a function of position, i.e. the gradient, combined with the velocity of the pickup object.
Regarding repulsion: Water is diamagnetic. That means that the little spins (i.e. electrons) orbiting the atoms of a water molecule tend to align *against* the applied field direction. These spins will experience a repulsive force, hence the levitation.