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US Navy's High-Resolution Radar Can See Individual Raindrops In a Storm
coondoggie writes "The U.S. Naval Research Laboratory (NRL) researchers said recently that a Navy very high-resolution Doppler radar can actually spot individual raindrops in a cloudburst, possibly paving the way for new weather monitoring applications that could better track or monitor weather and severe storms. According to an NRL release, the very high-resolution 'Mid-Course Radar' was used to retrieve information on the internal cloud flow and precipitation structure. The radar was previously used to track small debris shed from the NASA space shuttle missions during launch. 'Similar to the traces left behind on film by sub-atomic particles, researchers observed larger cloud particles leaving well-defined, nearly linear, radar reflectivity "streaks" which could be analyzed to infer their underlying properties,' NRL stated."
means you can avoid individual rain drops and keep your battleship dry.....
"Boss, I'll need some special equipment to see our data in the cloud ..."
How many raindrops are there in a storm?
So, another solid example of the "Pure science and engineering" stuff that NASA does bleeding into real world applications.
Kind of.
I am government man, come from the government. The government has sent me. -- G.I.R.
The Space Shuttle generally flew only under clear conditions (Challenger excepted, of course); I can't ever recall seeing a photo of the Shuttle taking off or landing in the rain.
Light rain, I can see this working, but a proper Texas Downpour (a.k.a. "cow pissing on a flat rock") is probably going to block the signal after 300m of heavy rain, even at higher energies. I'd be curious to hear what kind of rainstorms and what region of the country they were testing this in. Light mist in Seattle is very different from a tropical thunderstorm in Miami is very different from a squall line in Dallas.
moox. for a new generation.
If you can detect indvidual raindrops, I suspect detecting a marble sized radar target flying near or over the speed of sound is no problem whatsoever. While this radar is probably too big to put in a fighter a datalink from a ground based version to the fighter will solve that problem quite nicely.
>Doppler radar can actually spot individual raindrops in a cloudburst,
A raindrop, you say? Like what, a big one? Ok, that's 5mm across for the largest type. From here: http://hypertextbook.com/facts/2001/IgorVolynets.shtml
It's only a matter of time that other countries develop "weather radar" as pinpoint as this.
The F22 and F35 radar cross sections have been compared to a metal marble and a metal golf ball, respectively. Their "stealth technology" has just been rendered obsolete.
--
BMO
Seeing individual raindrops, that's the problem with current weather radar technology.
Or could it be that it's already so expensive that they cannot blanket the country like
they need to and there are huge gaps in coverage which makes models less accurate?
-AI
For me, it is far better to grasp the Universe as it really is than to persist in delusion
So, now that the current generation of stealth coatings on airplanes is obsolete, how long before the US starts to both A) Sell current-gen stealth to other countries, and B) develop next-gen stealth capability.
Remember, stealth doesn't mean a plane is invisible, it just means that the cross section of the plane is just too small to image using normal radar.
is about as useful as slashdot these days.
Their Stealth technology has been obsolete since before they came out, as long as you can use a heavy-ass ground (or ship) based radar system. Russian S400 "Triumf" deals with stealth just fine, and so does S300 with minor mods. And by "deals" I mean shoots down stealth aircraft from beyond its missile range. That's why we haven't attacked Iran yet. That's not the point of stealth. The point of stealth is that _other planes_ can't see you, and you can take them out from way beyond _their_ radar range.
I wonder about those two almost insignificant characteristics and related health azards.
Any idea?
Sent as ripples into the electromagnetic field. No single photon has been harmed in the process.
Then you can see a stealth aircraft displacing those raindrops.
I can do that too. What's the big deal?
-- Cheers!
Now I can't even take a piss in the woods without the government keeping track of the stream?
Until the russian equipment have shot down a raptor (or even a jsf, which is much easier target), I would be very skeptical about their claimed capabilities. And that skepticism goes both ways. Afaik the raptor is yet to see actual combat.
http://www.nrl.navy.mil/media/news-releases/2012/nrl-scientists-track-individual-raindrops-inside-clouds
Great, hopefully this will help me to work out a formula for a minimum droplet saturation walking speed when caught in the rain.
It is a Retina radar! Anyone?
And to manipulate such quantities of data - yet another thing.
And that another another thing is something to think about here. To calculate from raindrop up, or to take chaos theory shortcuts?
I really don't know much about meteorology and chaos theory, but I am sure people thinking about individual raindrop approach do not know, too!
http://opencm3.net, http://www.nongnu.org/gm2/
Someone wrote: "how many raindrops are there in a cloud?" I ask, "how many terrabytes are there in a cloud?. And will you be able to find the golf-ball in that cloud? Or does the USS Whatchemagot have BigBlue under the deck?
10 ?"Hello World" life was simple then
Stealth technologies are designed to change how an object that can be detected by RADAR is seen by it. Through various material changes, positioning of openings, angles, and the like, you can change how you appear on a RADAR and to a point minimize detection range. You do not have to penetrate foreign airspace much to get a bomb on target and drones don't incur the political risk of dead pilots.
Oh I do not doubt that current stealth technology can be rendered obsolete if not already in some cases, however while we read about breakthroughs in RADAR technology when it occurs we rarely read about stealth technologies until they are implemented or already surpassed.
Then comes the old standby, the military is most likely well prepared for not caring about stealth in the long run. With new weapon systems, drones, and the like, finding a stealth plane is least of the enemies worries.
* Winners compare their achievements to their goals, losers compare theirs to that of others.
Yes your post is consistent with the fact that the first stealth aircraft was - a bomber.
Seven puppies were harmed during the making of this post.
I said .042m/Sin (.00000413239/2) = 1164km
This is wrong.
I forgot to use the radius of the golf ball, which is .021
Which gives 582km instead, not 1164km
--
BMO
>Explaining what stealth is
Dude... don't do that. We know what it is. And for those who don't, google is --->over there.
>Oh I do not doubt that current stealth technology can be rendered obsolete if not already in some cases, however while we read about breakthroughs in RADAR technology when it occurs we rarely read about stealth technologies until they are implemented or already surpassed.
I was talking about the planes we have built. If you can detect a .5mm raindrop, at 2km, you sure as hell can detect a 42mm ball bearing - the current (optimistic) radar profile of the F35.
These airframes need to be relevant for the next 25-30 years (look at the life of the f-14, f-111, f-16, f-18 Hornet and Super Hornet, f-15 Eagle and Strike Eagle for comparison).
Somehow I don't think the stealth capabilities are going to be relevant in 5 years.
--
BMO
Nope. The Fokker E.III was a fighter.
Operation Guillotine is in effect.
So they saw me pee in backyard...i was just giving back to nature honest....had nothing to do with beer
*: The name of the fighter's mothership shall be left as an exercise for the reader.
What if we do some EW and raise the noise floor?
Most weather services can't even tell me what the temperature is right now or was yesterday. Maybe they should focus on reliably telling what the temperature will be and what the precipitation will be like before they start calculating individual raindrop trajectories.
Oh and by the way, this is impossible and they're lying. If there's a raindrop 500 feet into a pillar of rainfall, chances are it will be blocked so the radar waves would bounce off a raindrop closer to the edge first before even hitting an interior one. That's how radar works, after all. So they could track 1 raindrop on the very outer edge of a storm I guess, but that's even more useless.
Russian S400 "Triumf" ... shoots down stealth aircraft from beyond its missile range.
I had to read that twice. I thought to myself that if the Russian S400 can shoot down aircraft from its own missile range, that's quite impressive. Then I realized you were talking about the aircraft's missile range.
Increase the resolution and apply to fairy cake and we're good to go!
It is unwise to ascribe motive
there will eventually exist lawsuits where somebody did not receive their "tornado is hitting your house in 5 minutes" warning phone call/text message.
Well , this could be useful for detecting and counting migratory birds , provided that it doesn't fry them in flight.
What it can do----detect moving raindrops from space. What it will end up doing---sitting under a tarp in a warehouse in Virginia til it's yard saled to a foreign country in 2024
It's still not right. You typoed the angle from 0.000143239 degrees to 0.00000413239 degrees. Putting in the correct value, we get:
which is substantially lower than your figure. In situations like this, I'd recommend using a much simpler approach: a 42.67mm golf ball, compared to a 5mm raindrop, is (42.67/5) ~= 8.5 times as large, so it has the same apparent size when it's 8.5 times as far away. 8.5 * 2km = 17 km, as above.
You were very careful about the precise definitions of the angles involved; but in a case like this, it makes no more than a one-in-a-million (or, rather, 5mm in 2km) difference in your final answer, and it increases the odds that you'll make a mistake.
Unless you have a radar wavelength smaller than the size of a raindrop (\lambda 0.5 mm seems far-fetched), then you CANNOT SPOT INDIVIDUAL RAINDROPS. Furthermore, to achieve the kind of ANGULAR RESOLUTION required, would necessitate a HUGE-sized dish given that roughly speaking the diffracion limit is \Delta \theta ~ \frac{\lambda}{D}, where D = diameter of the dish. What the article says is that you can understand the size and distribution of MANY small raindrops in a cloud, which presumably before you could not. I am amazed how little basic physics /.-tters seem to know.
The point of stealth is to take out their radar sites. People declare that it's easy for radars to detect and shoot down stealth aircraft, but how easy is it for a stealth aircraft to blow up a radar site? I have to point out that no one has figured out how to make a stealth radar site yet. Think about this: the radar beam has to travel to the target, reflect, then travel back to the radar site to be detected by the radar. If the target has a bunch of antennas, it can detect the radar much earlier than the radar can detect it.
In any war, drones and cruise missiles will be the vanguard of the strike force. The UAVs will fly in to draw fire and jam radars, and cruise missiles will be used to hit anti-aircraft batteries that fire. Sure, in theory the radars can detect stealth aircraft but what about a real electronic warfare environment where we have jammers, target drones, and cruise missiles lighting up any radar site that turns on? The B-2 has its own electronic warfare suite, and as seen above, it can see radar sites much earlier than the radar sites can see them. And don't make any mistake: the radar sites are well within the reach of many of our aircraft. The S400 has a maximum engagement range of 400 kilometers. That is well within the range of the JSOW-ER with a small jet engine that can hit targets from 300 nm. The JASSM-ER has a range of 575 miles, which can be deployed by the B-2.
The B-2 carries the Joint Standoff Weapon (JSOW), which can hit targets from 60 nautical miles. There's a Small Diameter Bomb that can float 60 nmi. Any guy who turns on his radar will have a bad day, guaranteed.
A NYC lawyer blogs. http://www.chuangblog.com/
Jamming only works for so long, and it pretty much says "HERE I AM" after you "burn through" it. Imagine someone shining a super-bright flashlight in your face. Can't see now? That's jamming. However, put on some welding goggles (burn through the jamming) and suddenly that blinding glare is merely a point of light telling you EXACTLY where that person is.
For large sets, this will be our guide even unto death, for the LORD will work for each type of data it is applied to...
You arguments are purely speculation, because you have no idea the RCS of those planes and if you did you would not be able to talk about it, or at least be smart enough to post AC.
This is good news. Now we can finally settle the question of whether commercial passenger aircraft do, in fact, jettison the contents of their waste tanks in flight.
'The tyrant will always find pretext for his tyranny.' - Aesop's Fables
It's not that simple you need to consider R^4, when a radar sends out a signal it outputs the wave it like a cone, the further away the more spread out the signal is, once the energy hits the object the same thing happens in return so every time the radius doubles power is reduce by 1/16. Now lets look at the size of the objects a 5mm sphere has an RCS of about -50 dB or 0.00316w a golf ball sized sphere has an RCS of -25 dB or 0.056w. If the detection range is 2km at 4km they can see an object with .05056w or -25.92dB. This is not an exact answer as I would have to know the frequencies and air density to properly calculate the the returns of the object but suffice to say it is no where near 1164km it's more like 4.2km. Gain from antennas is a constant so even a focused beam will suffer the fate of R^4.
Knowledge = Power
P= W/t
t=Money
Money = Work/Knowledge so the less you know the more you make
this radar would have the sensitivity to track a 42mm ball bearing 10km, even though the sizes or significantly different every time your radius doubles the rx power decreases by 1/16 a 1mm diameter raindrop would have -80dB rcs or .0001w a 42mm sphere has an rcs of -25dB or 0.05623w it's about 10km that it could be tracked at bases on those values. At 10km any plane can deploy it's weapons and turn around before it gets any closer leaving the radar to track the missile that will hit it.
Knowledge = Power
P= W/t
t=Money
Money = Work/Knowledge so the less you know the more you make
Your jammers do not have to be in missile range or on your stealth plane to be effective. They may know where the jammer is but can't reach them.
Knowledge = Power
P= W/t
t=Money
Money = Work/Knowledge so the less you know the more you make
Shut up, Chrisq.
This is why you have 1 fan and 18 freaks.
Well, I guess that plan to infiltrate earth in tiny spaceships disguised as water drops is out the window now.
Thanks to the US Navy!
That's our life, the big wheel of shit. - The Fat Man, Blue Tango Salvage
The S400 has a maximum engagement range of 400 kilometers. That is well within the range of the JSOW-ER with a small jet engine that can hit targets from 300 nm. The JASSM-ER has a range of 575 miles, which can be deployed by the B-2.
I don't know much about this topic, but I suspect that the JSOW-ER can hit targets from a greater distance than 300 nanometers. I suspect that you mean 300NM (a.k.a 300nmi). See: https://en.wikipedia.org/wiki/nm
I've had radar operators work for me who could see flocks of birds skimming over the ocean, and certainly could see diesel submarine attack periscopes, with an airborne look-down version of the LN-66 radar. The LN-66 was an adaptation of a very standard commercial vessel navigation radar and was far from a sophisticated device, but in the hands of a really skilled operator--a Navy operator, I might add--even relatively unsophisticated radars can do some pretty remarkable things.
Can't see the storm for the raindrop?
Stealth aircraft have always been detectable on radar, the only question is "how much radar power" and "how close", and that still applies to indirect radar measurements as well. It's still harder to detect changes in moisture vs a B-52-sized hunk of aluminum glinting back at 100 km.
The real point of stealth is that mission planners know what range the stealth aircraft is detectable at, and the range that said aircraft detects its targets, and the range of its weapons. If it lines up, stealth craft launches in the gap and turns away.
Also, 'detection of stealth' (there is somebody out there) isn't always good enough to be able to accurately track to launch a missile which itself would be able to lock on.
STOP GIVING SKYNET NEW TOYS!
none
Except of course neither Raptor nor JSF can carry JSOW-ER, and it can itself be easily shot down by any SAM produced since early 80's, since it's not stealth. The planes that can carry it can be shredded into confetti by S400 from 400km away. And that's the officially advertised range, real range is likely to be greater than that. In addition, S400 has 360 degree radar detection with a range of 600km. So whoever turns on the radar trying to target it is going to have a really bad day, guaranteed.
Now we'll finally be able to ascertain with certainty the answer to the age old question... which raindrop WAS responsible for the flood?
They still can't detect fat rain.
You're missing the point when you conclude that "whoever turns on the radar trying to target it is going to have a really bad day, guaranteed." The first part is not true. Killer birds do not have to turn on its radar to find where your radar sites are. It is the S400 has to turn on its radar to detect targets. Killer birds can sit around passively sucking up radiation to hone in on radar sites. Due to the physics of it all, the killer bird gets to detect the enemy radar passively from a much great range than the radar site can detect re-radiated signals from the killer bird. The F-22 has thousands of radar sensors embedded into its skin so it can pick up radar signals at a very far distance; estimates are at about 200 nmi. But the Sentinel and other spy drones sneaking into your airspace in the weeks and months before the invasion are drawing maps of all of your radar sites and airfields. Before the first combat plane crosses your borders, they already know the location of most of your radar sites and a bunch of cruise missiles will be tasked to their destruction. Heck, if you're out in the boondocks near the border, there may even be a special forces group marching towards you and they will kill you old school with rifle and grenades while you're staring at your computer screens.
More importantly, there is no one "trying to target" the S400. The radar sites require humans to man and maintain. You need dudes staring at the radar screens, keeping them happy, taking care of the generators that make everything work, and reloading missiles and troubleshooting things. The drones in the vanguard of any attack that are flying suppression are not human. The guys that fly them are in Florida, and they work eight hour shifts, after which they go home and play with their kids. You don't get any relief. You sit there and fight until you die. At the end of the day, you're trading your S400 and crew for a bunch of JSOW-ER, drones, and other unmanned aerial combat systems. The S400 will not even get to test itself against a manned crew. The unmanned systems will pwn any S400, and mop up any radar sites that weren't in the initial maps. The stealth aircraft will fly in after enemy air defenses have been suppressed by a large extent, and by that point, only suicidal folk will be turning on their radars because doing so will be certain death. The manned stealth systems will be dropping heavy bombs on your commanders, and communication structures and the SEAD missions will be carried out primarily by the persistent stare drones just constantly floating around and patrolling the fire lanes use by the manned systems. You will not be resupplied. There will be no new missiles, more food, or medical supplies. The trucks and aircraft carrying those will have been blown up by US drones and the clips of their demise will probably be posted on Youtube. Your radio calls to your superiors will go unanswered because your boss already got blown to bits by bunker busters.
There's a saying: in theory, there is no difference between theory and practice, but in practice, there' is. The S400 has a theoretical range of 400 km and a theoretical detection range of 600 km on a good day. If you have sophisticated jammers actively fucking with you, and killer missiles trying to get detected so they can pwn you with a kamikaze charge, and you're expending missiles against JSOW-ER, and there's an unmanned aerial system floating around in theater constantly dropping these Small Diameter Bombs on you every fucking time you open fire on the JSOWs and decoy drones, and every time you lock onto something that turns out to be a stealth aircraft (which you probably won't because the manned birds won't be around until you're dead) the manned systems will have electronic warfare systems that burn out the detectors in the seeker head of your missiles, and towed decoys and chaff and flare and super-manueverability in the case of the F-22, then yeah, you're not going to be engaging at 400 km. I mean, at 400 km, your missile has no more energy and can't manueve
A NYC lawyer blogs. http://www.chuangblog.com/
Aside from Iraq (which didn't really have much in the way of weaponry), the US has never won a war in which it was a dominant player. Nuff said. All the bells and whistles, and yet the cave dwelling towelheads in Afghanistan are handing our asses to us. What makes you believe that Russians (or Iranians, with Russian weapons) won't be successful at it, in case a conflict breaks out? Why is the US scared shitless of invading Iran and North Korea, or, for that matter any country which has any decent weapons at all (Syria being a prime example)? Perhaps because those $150M apiece Raptors aren't as invincible as the spec sheet makes us believe? Heck, they've recently been found to suffocate pilots with no one even shooting at them. Take the loss of that F-117 in Yugoslavia as an example. Shot down with primitive weapons made in the 70's. Another one, damaged with the same weapons and unable to fly again. Serbs used a $50 rigged microwave oven which, guess what, looks like a radar to the passive radar detection system. That's what an enemy is capable of without adequate weapons. Now consider the kind of pain in the ass a proper army, fleet and air force can deliver.