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A gas will fill the container it is in. The pressure of these bubbles would be very low, maybe just enough to counter the gravity of the balloon.


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Sounds like they built a novel kind of vacuum chamber.

A larger balloon would have larger compressive stress over its entire surface. I'm very skeptical that could ever be made to float.


That's why you would use normal balloons filled with helium and graphite powder.

In a balloon?

Sad thing is, those balloons pop when they get too high. The density of air decreases, allowing the helium to push outward and pop the balloon. Had we made stronger balloons, we might have been able to just float up and collect them when we run out of light gases... Oh wait, that requires a balloon.

Isn't it a hydrogen balloon? Wouldn't some level of explosion be expected?

The balloon will never escape the atmosphere. It simply drifts higher until it either reaches neutral buoyancy, or pops. As the balloon rises, air pressure decreases. The result is that the gas inside the balloon is compressed less as the balloon rises, causing the balloon to expand.

In a flight like jgc's, the latex balloon expands until it pops. There are other balloons which can float at a steady altitude. One of these is called a "Zero-pressure Balloon." This balloon operates with a valve on the bottom. The helium will expand until it reaches this valve, then spill out. When the balloon loses helium, it loses lift. The valve will tend to dump helium until the balloon reaches neutral buoyancy. These balloons are so named because the pressure at the valve is the same as the ambient atmospheric pressure.

Another type of balloon is called a "Superpressure Balloon." These balloons maintain altitude by pressurizing internally. Unlike latex, these balloons stop stretching at a certain altitude. As soon as the balloon stops expanding, it maintains a constant volume. Buoyancy is based on the volume of fluid displace, so a pressurized balloon maintains the same altitude.

I work with a group of hackers attempting to cross the Atlantic Ocean using a Zero-pressure balloon. (http://www.whitestarballoon.com). A group of radio amateurs actually beat us to the punch (http://www.arrl.org/news/amateur-radio-balloon-flight-crosse...), their crossing was involved a large quantity of luck. We seek to develop systems and methods for engineering balloons capable of traversing large distances safely and reliably.


or a balloon that doesn't pop but just deflates

Pure nitrogen basically has the same density as air (Composing 80% of it). So a party balloon filled with nitrogen wouldn't float.

That kind of balloon wouldn't fly away, it'd just be blown up manually with air instead of helium.

Can you expand on what you mean by this? I researched online for this reference and consulted with some colleagues while discussing this topic but none of them could figure out what you mean by when the balloon goes up.

Good point, why don't we see nitrogen (gas) filled balloons?

A balloon?

A balloon needs air to float. When there's air, there's friction.

unless you've inflated a balloon

You can underfill a balloon so it has room to expand as it gains altitude...

Would a smaller balloon fly lower? Seems likely.

Kids play with current balloons because they’re elastic and bouncy. I think they would be bored of a perfect sphere that just hovers around the room.

Further, given that the vacuum balloons are rigid, I think it’s far more likely to take on a leak that fills the balloon rather quickly but not instantly. For argument’s sake, suppose one does fail suddenly- do we even know what that sounds like? I don’t think it could possibly be worse than a (thick enough) mylar balloon pumped up to two atmospheres and exploding. It’s not like suddenly there’s vacuum in the room.


If you inflate a balloon, you're not stretching out the dust on its surface.

Awesome. Here are a couple questions.

Is it possible to send a balloon up and not have it burst. Just float around for a few days?

How do you calculate the balloon size And helium needed for a given payload?

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