Chaff Cloud That Lit Up Radars as It Drifted Across Midwest Remains a Mystery | Hacker News Reader

Chaff Cloud That Lit Up Radars as It Drifted Across Midwest Remains a Mystery

thedrive.com

99 pointsmolecule38 comments

Chaff has always been a short term phenomenon - it settles, so how do you make it neutrally dense or even lighter than air so it will not settle. The key is related to the aluminum coated Mylar balloons - make them as light as air, Helium diffuses out quickly but if you use hydrogen you can create a chaff machine that uses two sheets of plastic, one coated with very thin aluminum. trap helium or hydrogen between them, then laminate and separate them into tiny tubes with neutral density so the residence time in air is quite a few hours with Hydrogen, lots less with helium. You can make it in advance, but popped popcorn fills a plane quickly, but unpopped corn allows you to mobilize more chaff in the plane. This would be a good method to fox radar guided missiles, or radar satellite surveys or launches. These short straws of Mylar would have the needed aerial residence time and could even be made to rise, loiter and then fall with the right choice of gasses (mixed hydrogen and helium allows a rise, followed by a fall as the helium diffuses out) - saves helium as well

both sheets need to be metallized to reduce diffusion across the film.

Interesting. I was looking at radar with my co-worker yesterday, we saw these scans and were like WTF is going on? Chaff from a C-130 huh? They do some interesting stuff with those planes. I worked on a project where we flew C-130 thru clouds, took pictures of the clouds and did data analysis etc.

Spent an entire summer analyzing pictures of ice crystals like this [1] in MATLAB. Fun times...

[1] https://www.eol.ucar.edu/instruments/two-dimensional-optical...

Might've been "smart" chaff to achieve this same thing.

Kinda like that fake tech they used in the movie Twister to map tornados.

They issued an update today with quotes from the West Virginia Air National Guard:

http://www.thedrive.com/the-war-zone/25451/a-west-virginia-a...

I thought of migrating birds, as they sometimes show up on radar, but there does not appear to be anything here[1] corresponding to this event.

[1] http://birdcast.info/live-migration-maps/

Update: I got the date wrong, this would have been Dec 10... Data is missing from 10:40 to 16:10 CT, and the spatial resolution is not high, but the map is showing medium rates of migration in that area at the later time.

Seems like the same people who search for meteorites could get a general location for where this went off radar and go walk around. Other than actual chaff, my mind goes to possible “black projects” when reading things like this. I can’t think of any possible applications though.

It looks like once this stuff has dispersed into the air, it is very fine and sparse, so there probably won't be much to see on the ground. Must do wonders for the local wildlife though.

Unless it's laced with some exotic heavy metal it's probably better for the environment than most plastics.

If it's thin aluminium foil, then it'll probably decompose fairly quickly. I'm more concerned about what will try eating it before it does so.

That’s a low bar for comparison.

would you settle for a black project researching new radar evasion and confusion techniques? Seems like a legit purpose and something companies and governments will be actively researching. This kind of research would be under nda / top secret or black project just depending on what entity would do it.

If you have a few seconds of position information of a meteorite, it’s possible to make a fairly accurate estimate of where it will come down. The effect of wind speed, air pressure and air temperature on the spot of impact is limited.

With less dense stuff that moves a lot slower, that’s a lot harder. This stuff may stay in the air for days, rain drops may take it to a lower air layer with different wind direction or down to the ground, etc.

This stuff went off radar either because it got dispersed or because it got too low for the radars to see it. In either case, it will be hard to predict where, if anywhere on land, it will come down.

"The Red Hills MOA is relatively large, including areas of both Illinois and Indiana. We don't know if the MOA was active at the time the plume appeared on radar, but it might help explain the incident."

The military releases "notices to airmen" (NOTAMs?) indicating when a MOA is in use, no?

I wonder if they will be able to put AI into missiles to detect Infrared decoys (flares, IR laser) or radar countermeasures (chaff, jamming).

Military countermeasures are really cool, if you can get past the whole moral dilemmas in working with technology like that.

There was rudimentary intelligence in missiles such as the BAe ASRAAM back in the late 1990s. For example extrapolating the shape of the target from the IIR image and rejecting objects that were non-geometric, or too small, or too consistently hot.

What moral dilemma? There are plenty of people who would kill (pick your group) on the spot. Being armed is good.

This comment is extremely naive. Once you create a weapon, you have no control over how its used by politicians years later. The engineers who made the avionics system for the Predator drones (just as a random example) are somewhat responsible for when those drones are used to bomb wedding parties, even if when they were developing the drone it was only intended for surveillance. Most of the people who would like to kill (pick my group), would like to do so because of careless use of advanced weapons systems by politicians who're only interested in the next election cycle. The politicians could never have bombed those wedding parties, and thus created the people that want to kill my group, if some very smart and morally bankrupt engineers hadnt given them the ability to do so. Being armed is only good if you trust the people who control those arms. I dont know where you live, but the guy in control of my countries military is a narcissistic cheeto with the IQ of a cuncused wombat, whos first week in office involved the authorization of a combat mission that resulted in more then 20 dead non-combatants [0], including a 4 year old child.

[0] https://www.cnn.com/2017/02/03/politics/yemen-raid-trump-oba...

"narcissistic cheeto"

strong (among other things...) argument there.

If dropping bombs on people is your metric, you might want to mention his predecessor.

Yes it was a terrible error for Congress to declare war against the Houthi in Yemen. Very few USA interests have been served by all the children we've killed there since March 2015.

Military tech, from an engineering standpoint, is always cool. Everything from aerodynamic designs to software control systems. But that's looking at the finished products.

A project on the other hand must be hell on earth. I can't imagine the level of bureaucracy needed to get anything done, or that the average engineer has any say on anything.

> I wonder if they will be able to put AI into missiles

Missiles arguably already have AI. It is a source of mild frustration for control systems engineers to note AI researchers "discovering" techniques and algorithms that are mathematically identical, or very similar to, things that have been known and used in control systems for years, decades even.

That's the downside of working on classified tech, right? You get huge budgets and work a decade ahead of civilian gear, but you're doomed to see civs reinvent your stuff and take all the credit.

For instance, the NSA had public key crypto long before RSA was discovered.

Yes, it happens in secret vs open but I'm talking about all open stuff. It just isn't sexy when control systems engineers do it.

You do realize we're in the middle of a fairly intense meteor storm, where lots of sand sized particles are turned to plasma when they hit the atmosphere, right?

It was even today's Google Doodle.

"chaff was released by a military C130 [sic] northwest of Evansville."

Not exactly a mystery.

Uncorroborated seemingly random claim on twitter as stated in the article.

Uncorroborated, and also the article notes that the duration of the cloud is unusual.

So why was it 50 miles across and in the air for 10 hours? That's not from a C130.

If the chaff had maximum surface area-to-weight ratio approaching spiders ballooning, <2.5 um dust particles and dandelion seeds, and there were enough thermals upwelling air in the area, it's entirely possible for chaff to persist as long as there is an average slight updraft gradient to periodically relift material.

Granted, it's of limited military value unless it were dumped in large quantities (such as an/several E- prefixed US mil aircraft flying air defense suppression/Wild Weasel) and such upwelling wind conditions were present. It's usually intended to create false echoes to misdirect a missile or break a radar lock in real-time with a starting velocity similar to the original aircraft, and then it has no purpose once it separates far from the launching aircraft.

Speaking of dandelion seeds, check out this video showing the vortex involved in their flight(1). I think it's beautiful.

https://static-content.springer.com/esm/art%3A10.1038%2Fs415...

Doesn’t the chaff need to be of certain lengths to match the frequencies of the incoming radar. I thought I read something about that in one of my previous wake cycles

Yes, peak scattering will occur at 1/2 wavelength, and multiples of that.

"By clicking continue below and using our sites or applications, you agree that we and our third party advertisers can:" break EU law and screw us over.

No thanks.

https://outline.com/36cJVa

It seems I need to use Outline to read the majority of articles linked here. Outline is a great site!

Does it work on paywalled pages like WSJ?

Isn't the notification exactly what makes it not break EU Law?

Also, "screw us over"?!? Erma gerd, the're gonna show us relevant ads. The end is neigh. The end is neigh. You must be a blast at parties.

I went ahead and tried anyways and got this error:

> Request has been terminated Possible causes: the network is offline, Origin is not allowed by Access-Control-Allow-Origin, the page is being unloaded, etc.

For such an AFAIK unknown blog, they really are making it difficult to get new readers.

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