Balloons vs orbit

[neilsox]

Featured today on the home page of space.com was a balloon launch from Sweden likely the next few weeks. Perhaps more important than the telescope data, balloon technology is advancing. Still far short of wildly optimistic projections by JP Aerospace and their proposed Deep Sky Station. The balloon is big = to a cube of helium almost 400 feet on an edge (bigger at altitude) that carries two tons to an altitude of 23 miles for 6 days, at a cost of $60 to $80 million dollars.
CNT with great specs should make the balloon less fragile, much increase the payload, or double the altitude, making many high altitude projects practical. Hydrogen can be used at high altitude as there is not enough oxygen for a fire.
Leakage remains a problem for both hydrogen and helium, otherwise the balloon could circle the Northern Hemisphere several times launched near the Equator. Neil

 

[MeteorWayne]

Your topic title is misleading. Circling the earth while floating in the atmosphere is NOT orbiting.

 

[CalliArcale]

I think he's using the term correctly, since he's comparing balloons versus orbiting satellites. He's not saying balloons orbit; he's suggesting them as an alternative to expensive orbital shots. He doesn't say much about satellites, but instead provides a brief overview of some of the advantages of using balloons for deep sky astronomy instead of scientific satellites, which are more expensive and, in general, not recoverable. A balloon-carried telescope could be launched many times.

I think the main drawback to balloons for this application is that the platform will not be as stable as a space telescope. That said, there are certainly other atmospheric observatories in the works, most notably SOPHIA, which is 747 based.

That said, the term orbit is actually used in aviation to mean other things, such as circumnavigating the globe. Bertrand Piccard circumnavigated the globe in 1999 aboard the Breitling Orbiter 3, the first time such a journey had been completed non-stop. The term "orbit" is also used to describe a roughly circular path used by aircraft wanting to loiter above a particular region for some reason (eg. military aircraft orbiting around some part of Iraq waiting to be called in on a strike or something).

 

[andrew_t1000]

I thought the term "orbit" meant to circle something.
Which brings up the idea of an LTA launch vehicle.
I guess anything but the idea of a great big phallic rocket, thrusting it's way into the bosom of the heavens on an ejaculation of fire is not butch enough.
What is stopping the development of an LTA launch system?
Surely we have enough helium for this.
The Los Angelis/Akron days are long gone!
We can fill more than one airship at a time!
We need to think outside the box people, especially now NASA has been gutted.

 

[access]

People have and are developing LTA based rockets(rockoons) as launch vehicle but none have substantial funding so a working prototype is a long ways off.

 

[scottb50]

I thought the term "orbit" meant to circle something.
Which brings up the idea of an LTA launch vehicle.
I guess the idea of a great big phallic rocket, thrusting it's way into the bosom of the heavens on an ejaculation of fire is not butch enough.
What is stopping the development of an LTA launch system?
Surely we have enough helium for this.
The Los Angelis/Akron days are long gone!
We can fill more than one airship at a time!
We need to think outside the box people, especially now NASA has been gutted.

I don't see why we couldn't do what we do now with super expensive satellites with LTA vehicles at high altitudes. Solar power could be used to maintain altitude and position as well as power transponders, just like it is on satellites. When needed they could be recovered and repaired, refurbished or refitted and sent back up for a fraction of the cost of launching satellites.

An array of LTA's at 100,000 feet could provide Worldwide communications and data transfer far cheaper then what is now done with satellites.

 

[andrew_t1000]

It was my understanding that a couple of companies have been working on just that idea.
Isn't it Lockheed that have been developing a rigid skinned LTA for just that purpose?
And if you are at 100,000 feet, it's almost space!
Boosting a craft like Burt Rutan's Spaceship 1 from there would be easier, less air resistance for one thing.

 

[scottb50]

And if you are at 100,000 feet, it's almost space!
Boosting a craft like Burt Rutan's Spaceship 1 from there would be easier, less air resistance for one thing.

Almost, but the advantage is pretty small especially if you have little or no acceleration to begin with. My point was you could use Solar power to hold position and altitude pretty much as long as you needed to do. Repair or upgrades could be done by recovering the balloon and sending it back up. Coverage at 100,000 feet would be less then in orbit but spot beams are all the rage anyway and you could build and maintain a lot of balloons for the cost of even a single rocket launch.

 

[EarthlingX]

Would it be possible to regenerate leaking hydrogen from air moisture ? Is there any moisture left that high ?

 

[scottb50]

Would it be possible to regenerate leaking hydrogen from air moisture ? Is there any moisture left that high ?

It really doesn't have to be Hydrogen, Helium or ordinary air would keep it afloat at that kind of altitude. For air you might have to use a small rocket to get to altitude, but once the air is heated and the balloon inflated, it could be set at any altitude.

With Helium you could launch from the surface by heating the gas, drawing off the excess gas and cool it for storage. Solar powered cooling and heating would easily maintain or change altitudes. At altitude fuel cells could power motors for maneuvering thrusters and Solar powered hydrolysis could recycle the water for re-use, a self contained system.

At 250,000 feet the line of sight is 614 miles. With 45-50 you would cover the globe completely. If the are all networked it's instant contact from anywhere to anywhere at less then a third, maybe a fourth of a similarly capable satellite system. Fly-back capabilities allowing routine maintenance and upgrade when needed then relaunch.

 

[EarthlingX]

I actually had in mind something a tad bigger, say 3x5x7 those cubes platform. It would only make sense, if it could stay aloft longer than couple of days, i think.
That could be a nice launching platform for many things, since it's already over half a way (250 000 feet = about 76 km) upstairs.
It would probably simplify rocket engine bell design, since outside pressure doesn't change that much from that point on.
3x5x7x2t = 210 t

 

[MeteorWayne]

I still don't see how this works. Balloons float because they are more buoyant than the surrounding medium. At 76 km, it's a vacuum. Where does the buoyancy come from???

"In physics, buoyancy is the upward force that keeps things afloat. The net upward buoyancy force is equal to the magnitude of the weight of fluid displaced by the body. This force enables the object to float or at least seem lighter."

If it's a vacuum, what is being displaced by the balloon???

 

[drwayne]

By convention, many put the boundary between exo- and endo-atmosphere at 100 KM, but there
is still sensible atmosphere above 100 KM. (Satellite engineers have to keep track of induced
drag and heating well above 100 KM)Clearly though, to acheive lift at extreme altitudes requires
large balloon volumes, and very low density materials.

Wayne

 

[drwayne]

I think the altitude record for a balloon is somewhere in the low 50's of kilometers, but my memory may
be faulty...

 

[MeteorWayne]

From what I've been able to find so far, the manned ballooon record is 34.6 km, and the unmanned 53.0 km.

Realistically, over that height, there isn't enough atmophere to be buoyant in, so some major rethinking of the subject of this thread seems to be in order. And these were relatively light payloads, not launch platforms and launch vehicles.

It might be time to move this out of Missions and Lauches to Science Fiction.....

 

[ittiz]

Floating near the edge of space in a balloon doesn't give you too much of an advantage. You need speed to get into orbit, regardless of where you start from. Although one idea I had was to make a giant ridged tubular shaped telescoping airship. Telescoping so it could still be ridged and expand as it rose at the same time. It would be great if the inside could contain a vacuum instead of a gas, that way you get maximum buoyancy. But as of yet, nothing has been designed which can do that. It might be possible with carbon fiber I guess, if someone could figure out how to use the tensile strength of the fiber to hold the airship from crushing.

 

[CalliArcale]

From what I've been able to find so far, the manned ballooon record is 34.6 km, and the unmanned 53.0 km.

Realistically, over that height, there isn't enough atmophere to be buoyant in, so some major rethinking of the subject of this thread seems to be in order. And these were relatively light payloads, not launch platforms and launch vehicles.

It might be time to move this out of Missions and Lauches to Science Fiction.....

Only because nobody but me seems to have grasped what the original post was about, which didn't mention rockoons or impossible space-traversing balloons. It would be nice if at least one person other than myself would respond to the actual thread topic before deciding that this thread is science fiction (which, incidentally, it is not; "science fiction" suggests it is intended to be fictional, that it is art).

With that in mind, I am going to make a bold effort to discuss the topic, starting with my next post. Hopefully I will not be alone.

 

[CalliArcale]

Featured today on the home page of space.com was a balloon launch from Sweden likely the next few weeks. Perhaps more important than the telescope data, balloon technology is advancing. Still far short of wildly optimistic projections by JP Aerospace and their proposed Deep Sky Station. The balloon is big = to a cube of helium almost 400 feet on an edge (bigger at altitude) that carries two tons to an altitude of 23 miles for 6 days, at a cost of $60 to $80 million dollars.
CNT with great specs should make the balloon less fragile, much increase the payload, or double the altitude, making many high altitude projects practical. Hydrogen can be used at high altitude as there is not enough oxygen for a fire.
Leakage remains a problem for both hydrogen and helium, otherwise the balloon could circle the Northern Hemisphere several times launched near the Equator. Neil

Certainly, there's a lot of astronomy you can do from a balloon. For instance, you can learn a lot about cosmic rays up there. Frequencies that are filtered by the atmosphere are not filtered (or at least not filtered as much) when you get above the thickest parts of the atmosphere. I think in many cases, the main limitation is duration. With a balloon, you're only going to be up for a few days, and I think that's the main problem for many applications. If you want to make repeated observations, you'll need to buy new balloons. For a two-ton payload, you'll be at least doubling the launch cost in order to buy a big enough booster, so once you've decided you want to collect data for three one-week sessions, you've paid for the launch vehicle. (Not for the costs of making your payload able to survive in space without attention for months on end, though, or for operational costs for something in space.)

Still, JP Aerospace's new balloon is cool, and I bet someone will buy it. If you don't need more than a week's worth of data collection, you can save a lot of money this way. You might even be able to go with fuel cells instead of solar panels, since it won't need to operate for more than a week, which means you may wind up with more power available than you would have on orbit.

 

[MeteorWayne]

Good point Calli, and I apologize neilsox. I reacted to the title alone, and din't read your OP all the way thorugh. Must have been one of those bad days in Moderator land

Calli is not only much smarter and patient then the rest of us, but she's avoided most of the woo wars that have made some of us overly cranky at times lately. Mea Culpa.

I will now go back and reread the thread with my geek eyes open. :geek: :ugeek:

 

[CalliArcale]

I got kinda cranky at you there, and I'm sorry for that. Bad day for me too; I was a little cranky because of something totally unrelated.

I just dug up my brother's thesis, and my recollection was correct: it included data from a balloon experiment called CAPRICE. His work was far underground, at a neutrino detector. But you have to know what's happening to muons in the atmosphere to know what to make of the data you get underground, and that's where balloons come in. They're gentler (and potentially cheaper) than airplanes

Cosmic Ray Muon Charge Ratio in the MINOS Far Detector

So then I went and looked up CAPRICE. It's got a home with some interesting information, including a picture of one of the balloon launches.
CAPRICE Home Page

 

[bdewoody]

I watched a program on the science channel several months ago about this subject. They were launching from somewhere in Scandinavia. Their biggest problem was surface weather which delayed the launch several times. Apparently a lot of science can be done with balloons and at a much reduced cost compared to launching a satellite.

The other subject in this thread is interesting too. Maybe I'll do a little online reseach and start one concerning the use of lighter than air base platforms to launch manned or unmanned orbital vehicles.

 

[scottb50]

Only because nobody but me seems to have grasped what the original post was about, which didn't mention rockoons or impossible space-traversing balloons. It would be nice if at least one person other than myself would respond to the actual thread topic before deciding that this thread is science fiction (which, incidentally, it is not; "science fiction" suggests it is intended to be fictional, that it is art).

With that in mind, I am going to make a bold effort to discuss the topic, starting with my next post. Hopefully I will not be alone.[/quote]

I think my responses have been directed specifically to the original post. That I have tried to expand on the idea with other uses of the capability seems to address the content. True some of the other comments have strayed, even though launching from a balloon has been shown to be of little advantage a number of times, here, it still comes up.

That a balloon hasn't reached and stayed at 100,000 feet or higher doesn't mean it can't, it just hasn't been tried. The SR-71 reached more then 80,000 feet, and probably higher, and there has to be a point buoyancy gives out. Just like water there has to be a definite boundary, or cutoff point that would allow a balloon to float at the maximum altitude. Above that you obviously have to have enough velocity to orbit, but that too is not a part of the original post.

According to what I can find 60 miles, or 316,000 feet is pretty much the absolute, defined, top of the atmosphere, up to there it is no different then floating a boat on water, a big enough balloon could float on the surface. The biggest problem is most people think of it as rising from the ground and not having any control over the temperature or volume of the balloon. By heating, cooling, and storing the lifting gas altitude can be varied and controlled as needed.

 

[EarthlingX]

I apologize for being a little off the thread topic and as a token of my repentance i present to you this couple of links:
Earth Atmosphere Model (metric units) : http://exploration.grc.nasa.gov/educati ... osmet.html
Earth Atmosphere Model (english units): http://exploration.grc.nasa.gov/educati ... atmos.html

I found this here : http://exploration.grc.nasa.gov/educati ... hortr.html

 

[drwayne]

I got kinda cranky at you there, and I'm sorry for that. Bad day for me too; I was a little cranky because of something totally unrelated.

I just dug up my brother's thesis, and my recollection was correct: it included data from a balloon experiment called CAPRICE. His work was far underground, at a neutrino detector. But you have to know what's happening to muons in the atmosphere to know what to make of the data you get underground, and that's where balloons come in. They're gentler (and potentially cheaper) than airplanes

Cosmic Ray Muon Charge Ratio in the MINOS Far Detector

So then I went and looked up CAPRICE. It's got a home with some interesting information, including a picture of one of the balloon launches.
CAPRICE Home Page

My cousin spent years in a Russian mine on the neutrino problem. Ended up with a Russian wife.

Wayne

p.s. I don't think I mentioned SciFi, just altitudes

 

[MeteorWayne]

No it was me (TOW- The Other Wayne) who did that and I was wrong regarding the original subject. As I said, I'm sorry.

I may split off some of the posts related to rockoons (which was NOT the original subject) to the related thread is Space Business and Technology as my penance.

TOW (MW)