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It looks like the large size is mostly just solar panels (I'm assuming that's what they were; they could have been 'sails' to help steer it) and their scaffolding. From some of the available photos there's two wings, each with eight panels.

There's a tradeoff between the weight of the solar panels vs simply using batteries (though batteries don't like the cold, and solar panels do), so I think maybe they were hoping the thing would stay aloft for a long time?

My guess is that the actual package of equipment - batteries and sensors - is quite small. Maybe a telescope and gyro stabilizer or gimbal was part of the setup. Insulation probably bulked it up quite a bit; it's very, very cold at that altitude.

I'd be curious what sort of uplink they were using, assuming the thing was actually fully functional as a spying device. I'd say there is a decent chance it was largely a dummy, designed to see what our reaction would be.

I don't particularly like the precedent we just set. There's no evidence it was a weapon, its flight path was easily tracked and slow so our military could hardly argue it was a surveillance threat especially compared to satellites, it's well outside commercial aviation flight ranges.

If they want to send balloons over us at 80,000 feet...let them? Who cares? They can task commercial satellites and get as good or better imagery.

We can hardly point fingers. The U2 flew at similar altitudes, we still use them to this day, and they almost certainly contain far more powerful spying equipment.



> they could have been 'sails' to help steer it

Sails are useless in a balloon. The only way to steer a balloon without a propeller is to raise and lower its altitude seeking a wind blowing in the right direction.


Why not?

Add a fin to a baloon and you can steer it.

And once the baloon can hold direction in the wind with the help of the fin, you can add sail to actually get some propulsion in direction other than wind.


The balloon moves with the wind. You cannot steer it because from the point of view of the balloon it is not moving.

There is no keel on a balloon. Without a keel, one is only going downwind.


> from the point of view of the balloon it is not moving.

Mind == blown*

*Sincere, but pun intended


I think you should be able to on a wind current boundary


Wind is still flowing over the balloon and able to generate a steering force.


No, as Walter said, it's moving with the wind, i.e. it has the same speed as the wind. It's only if there's a sudden gust that you would see anything flowing over the balloon. I took part in a balloon experiment a couple of years back, essentially a weather balloon with several cameras, including one pointing upwards - we could watch (after we retrieved the cameras later) hours with footage of the balloon itself. There were various loose threads etc, and I assure you - there wasn't much movement! Occasionally there would be a little gust, when that happened the payload would swing around a little bit, but for the most part it was very quiet. Particularly at the highest altitudes.


Forgot to include: We had microphones up there too! It was literally quiet.



The problem at 60k feet is actually you are above the weather and don't have a ton of wind to work with. Moving up and down in the minor wind currents is far more efficient energy wise and practically.


especially compared to satellites

It is a lot easier to take pictures and collect data at 60,000 ft (balloon) than from a satellite in low earth orbit, which is closer to 6,000,000 ft.


They also could have had ground penetrating radar. Note the path of the balloon was over the US missile silos

https://geo-matching.com/content/new-approach-to-use-ground-...

Outside the atmosphere you would not be able to do it


You could.

The Space Shuttle flew missions with an imaging radar that discovered ancient riverbeds beneath deep sand in the Sahara. At the time, some thought it would have worked equally well to disclose buried military infrastructure.

https://www.jpl.nasa.gov/missions/shuttle-imaging-radar-a-si...


Not just silos, going through the Dakotas and Missouri put it fairly close to Ellsworth and Whiteman, as well.


If that thing had a radar strong enough to see through dirt from 50,000ft, it should have also been causing havoc to all sorts of electrical equipment too.


I know nothing of radar, but could the radar be shaped like routers beam forming? Couldn’t the radar also be switched off over the majority of inconsequential areas?


> could the radar be shaped like routers beam forming?

Yes, SAR [1].

[1] https://www.earthdata.nasa.gov/learn/backgrounders/what-is-s...


SAR is just a method to virtually increase the aperture of the antenna with a moving platform, it is unrelated to the localisation of the beam


Okay, genius: explain how easy it is to generate as good imagery at 80,000 feet (almost ten times the typical aerial imagery altitude) from a platform being buffeted and spun and tilted by the wind with the weight restrictions of a high altitude balloon.

Now compare that challenge to simply setting up a shell company and purchasing 15-30cm commercial satellite imagery in their choice of bands.

Commercial satellites can generate 15-30cm images good enough to tell what make and model a car is in a parking lot. https://blog.maxar.com/earth-intelligence/2020/introducing-1...


> explain how easy it is to generate as good imagery at 80,000 feet

Camera gimbals provide image stability regardless of motion in 3D space. Digital post processing is used to clean up images from planes and other moving sources.

> with the weight restrictions of a high altitude balloon.

People seem to really underestimate the size of these balloons. They are hundreds of feet across and capable of lifting massive loads. Using Google's Loon as an example it had a balloon that weighed almost 200 pounds and carried an additional 175 pounds of solar panels before you even added the mission payload.

> compare that challenge to simply setting up a shell company and purchasing 15-30cm commercial satellite imagery

Satellites have predictable passes and military installations schedule sensitive outdoor activities around them. The problem for defenders with balloons is that they can loiter on station for months at a time making scheduling around them impractical.


Try scheduling activities around all those Starlink sats.


> I don't particularly like the precedent we just set

especially in view of the fact that the upper limit of sovereign airspace is not defined by international law. In fact there are proposals to treat the 18-160km zone as a transitional region of reduced sovereignty akin to EEZs.

https://iaass.space-safety.org/wp-content/uploads/sites/24/2...

> Legally however, it is an indistinct region where it is not clear whether the operations that take place are covered by aviation or space conventions and treaties, in particular with reference to the freedom of overflight that applies to space orbital operations

Also:

> Although outer space is free, if states are allowed to claim vertical sovereignty up to the point where orbital dynamics are possible, other states will be precluded from having free access to space

> John A. Johnson, General Counsel of [NASA] and [of USAF], said in 1964 "there should therefore be no legal basis for protesting, merely on grounds of unpermitted presence, the overflight of national territory by ascending and descending spacecraft, regardless of altitude."

https://scholar.smu.edu/cgi/viewcontent.cgi?article=1126&con...

Also see:

https://aviation.stackexchange.com/questions/43439/is-there-...

https://en.wikipedia.org/wiki/Air_sovereignty


While that’s an admirable goal, in practice this is an operation above or in US airspace, which seemed to be unannounced by another nation state. There is little wiggle room for an honest blunder. China could have send out a press release their balloon was out of control or whatever.


I agree the visibility makes it worse, but my sense is that stratospheric balloon overflight is something that happens fairly frequently and most of the time does not cause diplomatic incidents (which explains why we heard nothing about it the 4-5 times it happened in the past several years). Another instance is this Google balloon that recently fell out of the sky in the Congo: https://twitter.com/kambale/status/1621811081206439937


When an aircraft doesnt have a transponder, doesnt respond to radio calls, no flight plan on file, and seems to be adrift, it is a hazard to navigation irrespective of altitide. Such things get intercepted and, if in any way dangerous, are shot down. Post-9/11, there are even protocols for shooting down unresponsive airliners.


Name one plane that flies at more than 60,000 feet, I'll wait.


If you believe the Chinese officials, they had lost control of the balloon. Things that go up must famously go down, though that's not their department said Wernher Von Braun.


It's a bit strange how they are simultaneously upset that their balloon got shot down and claiming they had lost control of it.


The "upset" part is a defensive attack, they expect to avoid rebuffs of violating airspace by being very upset in the first place.


The only thing I find strange is that they didn't throw in something about hurting the feelings of the Chinese people[0] for good measure. They like to call this Wolf Warrior diplomacy; but it really comes across more as crying wolf diplomacy.

[0] https://en.m.wikipedia.org/wiki/Hurting_the_feelings_of_the_...


Well it gives a good excuse to shoot down US spy balloons or planes. The precedence has been set, and the snowball continue to roll downwards.


That precedence was set way back in the late 1950s when the Soviet Union started shooting at US U-2 spy planes, and especially in 1960 when they finally succeeded in shooting down the US U-2 spy plane with pilot Gary Powers.

This overflight was termed by the Soviets as an "Act of aggression". This Chinese incident is no less an act of aggression, and merely continues the precedent.

If the Chinese really wanted it considered otherwise because they had actually lost control of the device, they could have easily warned us of the problem and requested coordinated assistance in recovering their device (which would of course allow us to examine it). The PRC govt did no such thing.

And the critics complaining about not shooting it down sooner are ignoring two key things. First, the payload was 2-4 school-busses in length, and dropping such a thing from 12+ miles up in a random location even in sparsely populated areas is a ridiculous hazard. Second, we can be quite confident that the US military could neutralize any data collection or transmission during the transit, and the shoot-down over our waters eliminated the possibility of PRC recovering any stored data.


The U-2 can fly at 70,000 typical missions are 60-65,000ft.

https://en.m.wikipedia.org/wiki/Lockheed_U-2


Are the U-2s still flying in any numbers? The SR-71s? If they were, would a few balloons be a serious risk to their navigation?


Yes. Here is where you apply if you want to fly them.

https://www.beale.af.mil/Library/Fact-Sheets/Display/Article...



An aircraft that last flew decades ago is not relevant here.

The comment you replied to says "no commercial aircraft flies at that altitude" and the concorde hasn't flown in decades.


Well.. November 2003, so only after that can you claim "decades", plural.. it's a while yes, but clearly shows that at least it's in the realm of commercial aircraft, and may happen again, in principle.

Edit: By the way, that comment said, and I quote, "Name one plane that flies at more than 60,000 feet, I'll wait."

No word "commercial" there. So, aside from the Concorde, there were/are several others, some already mentioned.


No Concordes any more I'm afraid. There are no military or civilian planes that fly that high -- unless the CIA dusts off a U-2. There is no navigation risk.

In contrast, every orbital launch has to deal with 10s of thousands of pieces of space debris.


Several military airplanes, including fighters, can and do fly that high and more. I never said anything about navigation risks - that was from other posters. Obviously space debris is a much higher daily risk, for satellites.


Um, the Air Force still uses the U-2. As does NASA.

https://en.wikipedia.org/wiki/Lockheed_U-2#Operators


The F-15 and Eurofighter Typhoon have published service ceilings of 65000ft, put them in a vertical climb and they will go a lot higher than that, the Streak Eagle reached 103000ft.


Still can't see any risk. You won't find F-15s flying that high except if they need to shoot a balloon.


Possibly apocryphal SR-71 story ;-)

SR-71: "QQ requesting clearance to flight level 600"

ATC: "QQ, climb and maintain flight level 600... if you can get there."

SR-71: "Roger, descending to flight level 600"


U-2 (TR-1), SR-71, WB-57


Don't forget the beautiful XB-70


The original design is something out of Macross: https://en.wikipedia.org/wiki/North_American_XB-70_Valkyrie#...


All that's missing is it shooting out its missiles in Itano Circus swarms.


Haha yesss! I remember that post from a couple days ago. Really cool. I don't watch anime myself but the Itano missile effect is pretty sweet to behold


No longer in active service.


The U-2 is very much in service. Apply here if you want to fly it.

https://www.beale.af.mil/Library/Fact-Sheets/Display/Article...


> The U2 flew at similar altitudes, we still use them to this day, and they almost certainly contain far more powerful spying equipment.

And if they could, other countries would love to shoot them out of the air and it would be fair. You don't put planes like the U2 in operation without being aware of the risks.

I don't understand what you're trying to achieve by pointing that out.


It could’ve actually been a “science experiment” just launched at the behest of the military as a test like you say. So they’d have plausible deniability like the “fishing boats” in the South China Sea


Why would there need to be any plausible deniability for flying a spy aircraft over another country?

The U-2 spy plane did just that, as did Project Genetrix (Unmanned surveillance balloons), and then later, the SR-71 Blackbird, and as much as the Soviets complained, complaining and shooting at them was pretty much all they could do.

They shot down/recovered so many Project Genetrix balloons, in fact, that their left-over radiation-hardened film was re-used by the Soviet space program in their Luna 3 Moon probe.

All the sound and fury around this seems to be a serious case of 'the shoe is now on our foot'.


> Why would there need to be any plausible deniability for flying a spy aircraft over another country?

Because they’re denying it. Presumably, they’d want their denial to be plausible.


Is the US supposed to not complain now just because the USSR got to complain first?

If something flies over your country, you get to loudly complain about it and shoot at it.

If you are able to hit it too, good for you.


>They can task commercial satellites and get as good or better imagery.

Is that true? Just from quickly poking around, LEO satellites seem to orbit at about triple the height, moving far faster than a balloon lazily floating along the jetstream. Probably can use a larger variety of instruments as well.


LEO (300-1500km) is much higher than the apparent 60,000 ft altitude of this balloon (18km).


I'm mildly embarrassed to say I didn't even notice the discrepancy in units. Obviously, 200,000 ft (or 300k, but 200 was the figure I saw first) isn't really plausibly high enough to constitute orbit.


> about triple the height

Hundred times the height, to be exact.


> solar panels (I'm assuming that's what they were; they could have been 'sails' to help steer it)

Or perhaps both at once. I really hope the details of this craft are published, the machine nerd in me needs to know.


I don't know why you are downvoted but I agree with your point that the shooting down feels a bit like an overreaction.

For instance, the Pentagon has just reported that several Chinese balloons have been crossing US airspace in the recent years [1], also during Trump presidency. These were not shut down, they were not even reported at the time AFAIK.

[1] https://www.businessinsider.com/conservatives-blame-biden-ch...




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