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U-2 pilot's selfie above China's balloon taken over Missouri

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Re: U-2 pilot's selfie above China's balloon taken over Missouri

#141

Post by mfkp »

snypher wrote: post #140
mfkp wrote: post #82

Earlier quoted context omitted.

$100k of solar? 360w panels are sub-$300 at full retail prices. So that's under $5k of panels (unless you're including batteries in the calculation, but even then, it's maybe $10k).

Where are you finding these panels? Renogy is over $1/W and they have usually been price competitive

https://a1solarstore.com/solar-panels.html

370w panel for $266 (there's lots of good deals out there if you shop around).

If you want to save more money and buy by the pallet (22 panels), they're around $182 each for 330w: https://sunelec.com/shop/solar-panels/suniva-330w-solar-pane...

Re: U-2 pilot's selfie above China's balloon taken over Missouri

#142

Post by prpl »

BenjiWiebe wrote: post #128
prpl wrote: post #106

Earlier quoted context omitted.

That’s true but it assumes it can get within ~40 miles as the crow flies of an interesting target, even then you are going through a LOT more dense atmosphere for your photos.

The satellites still have to take photos through the atmosphere. All of the atmosphere, in fact.

It's an optics problem. Most of the scattering when looking down is near the objects because that's where the turbulence and air density. Looking sideways has to go through all of that - it's dense, uniform, and turbulent in comparison to the atmosphere above a point.

Another way to reframe this is that you would get a higher resolution looking at an object 100 miles down from space then you'd get looking at an equivalent object 100 miles up.

(Keyhole satellites are at 200 miles.)

Of course, knowing when satellites are above you is a bit easier to know and prepare for (the governments usually know where sophisticated adversarial satellites are). The smaller satellites I think are quite a bit higher - 300 miles - so the balloon can probably beat them provided it can get with 100 miles (even though there's a lot of those).

Re: U-2 pilot's selfie above China's balloon taken over Missouri

#143

Post by dreamer7 »

carabiner wrote: post #76
dreamer7 wrote: post #65

Apologies for the naive questions in advance. Is it not possible to go up there in a hot air balloon to inspect it from a closer distance? Also, what about base jumping onto it? Are there any methods of getting it back to the ground intact?

BASE jumping? Are there structures 60,000 ft tall?

Oops. I meant to say skydiving.

Re: U-2 pilot's selfie above China's balloon taken over Missouri

#144

Post by [deleted] »

imiric wrote: post #138

Cool photo, but it's ironic that an alleged spy balloon is being monitored from a spy plane. There's public outcry over China spying on the US, yet this same plane has been used to spy on many other countries for decades now. It's much more sophisticated, and not even state-of-the-art anymore. This whole story feels sensationalized, and like a diversion tactic.

[deleted]

Re: U-2 pilot's selfie above China's balloon taken over Missouri

#145

Post by zamnos »

onepointsixC wrote: post #69
jpgvm wrote: post #30

Pretty interesting platform. Looks to have around 16x300W solar panels, so roughly 4.8KW. A lot but no unreasonable given it has 4 electric turbines and it would take a lot of grunt to influence a balloon of that size especially given air density altitude. If it is a civilian craft it's either government or maybe one of the big Chinese universities. Supporting the spy angle is the pretty obvious connectivity (looks t…

>Supporting the spy angle is the pretty obvious connectivity (looks to be Ku-band satellite or similar) but it also doesn't really make that much sense... surely a satellite does what this does but better? China has no shortage of high quality spy satellites. Two things. It will be significantly better at ELINT, soaking up signals over which it floats. Second, at 60,000 feet it is at least an order of magnitude close…

This bears repeating. Physics dictates that atmosphere effects means a spy satellite, operating from the edge of space, will never be able to resolve the license plate of a car. A balloon, at 60,000 feet, roughly 18 km (space is at 100 km) can. If you're China, and you want high resolution aerial photography of US nuclear missile silos in Montana, this is what you'd use.

We've been at the limit since the 70's, btw. The Hubble space telescope was enabled by the spy satellite program - they didn't just "happen" to have an extra mirror of exactly the right size, they made them for spy satellites.

https://www.nextbigfuture.com/2019/09/us-spy-satellites-at-d...

Re: U-2 pilot's selfie above China's balloon taken over Missouri

#146

Post by zamnos »

testTED wrote: post #102
jvanderbot wrote: post #48

Earlier quoted context omitted.

Cell phone snooping they say, but that seems easier from the ground.

How?

Ship the equipment in, inside an unsuspecting container, on a container ship from China headed for the US. Send two spys in as tourists. Have them rent a truck, pick up the equipment, and just drive it around in target areas.

Re: U-2 pilot's selfie above China's balloon taken over Missouri

#149

Post by _kbh_ »

titzer wrote: post #56

Maybe they weren't just surveilling, but actually attacking cell networks and/or mobile phones through a vulnerability that requires line-of-sight. Just speculation though. Could also just be a distraction from something else they were up to at the same time.

> Maybe they weren't just surveilling, but actually attacking cell networks and/or mobile phones through a vulnerability that requires line-of-sight. Just speculation though.

Wouldn't it be easier to get LOS to all the same targets without drawing attention to yourself via something like a car or a normal airplane?.

Re: U-2 pilot's selfie above China's balloon taken over Missouri

#150

Post by IshKebab »

iisan7 wrote: post #77

The full twitter thread is worth a read ( https://twitter.com/gbrumfiel/status/1628776107301273601 ). Brings to mind the story in December 2022 about confirming the B-21 hangar location from the night sky in a press photo ( https://news.ycombinator.com/item?id=33912401 ). Not enough of the sky for that here though. Wonder if folks in this space have a more automated process to recognize the landscape rather than "Hel…

And in a similar way the location was never actually secret in the first place.
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