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US Navy's High-Resolution Radar Can See Individual Raindrops In a Storm
- yock 14y agoThe article doesn't mention anything about the physical dimensions or the power requirements, but I wonder if putting this on a mobile platform would be at all practical. It's one thing to put them on common storm paths, but imagine aiming a few of these at different axis at a tornado. Being able to analyze the motion of individual bits of debris in a tornado would teach us a lot, I think.
- forgotusername 14y ago> 3MW power So "not small" at a guess.
- shabble 14y agoThat figure is almost certainly the peak pulse power, not the actual supply requirements. Modern radar almost all operate by firing very very short pulses at relatively low repetition rates[1] I don't know about the system in question (and if it's still a prototype, it's going to be bigger than it could be), but I think I've heard of systems with similar pulse power being installed in (fighter) aircraft. [1] https://en.wikipedia.org/wiki/Pulse_repetition_frequency https://en.wikipedia.org/wiki/Pulse_repetition_frequency
- vonmoltke 14y agoFighter nose radars are still in the kilowatt range. Those systems are also rather light (~700lbs all totaled, not counting coolant). There may be pylon-mounted systems that get to the upper end of that (>100kW). High power airborne radars are typically carried by larger, purpose-built platforms such as the E-2C, E-3, and E-8.
- icegreentea 14y agoThe radar they are using is a component of the ballistic defense network. Unfortunately, there are a lot of 'mid-course radars' in those schemes. On a hunch, I think they're referring to this one http://www.globalsecurity.org/space/systems/sbx.htm http://www.globalsecurity.org/space/systems/sbx.htm. It is mounted on a semi-submersible platform.
- IanDrake 14y agoPHP gets the spear, but objective-c gets a pass? I'm not a PHP dev, but at least I can look at it and understand it. Beauty is in the eye of the beholder I guess.
- IanDrake 14y agoHah, how'd this get posted here! Sorry.
- espeed 14y agoWill this help in detecting stealth aircraft since modern stealth aircraft have signatures of large insects (http://en.wikipedia.org/wiki/Stealth_technology#Measuring http://en.wikipedia.org/wiki/Stealth_technology#Measuring)?
- cjg_ 14y agoStill need to distinguish between a large insect and a plane having the signature of a large insect. Otherwise you'd have a lot of false positives.
- waterlesscloud 14y agoIf it can track it continuously, I imagine speed will pretty much clear up any confusion.
- cjg_ 14y agoYeah, continuously is the point here. The frequency of the data points is largely dependent of the distance to the object. And you need to be able to identify the object in two subsequent images. I guess there's not that many insects at high altitudes either.
- enjo 14y agoCan't imagine that would be terribly difficult. They don't move like large insects for sure.
- fidotron 14y agoYou'd think in that case one large insect would move a lot faster than the other.
- johnhess 14y agoSeeing stealth aircraft isn't about resolution. The key to seeing something with radar is signal-to-noise ratio. From the article: "it becomes possible to measure the properties of individual raindrops greater than 0.5mm in diameter due to the low concentration of such drops in naturally occurring cloud systems and the overwhelming dominance such drops have on the measured radar reflectivity when present in a field comprised of smaller particles." It's easy to distinguish an airplane from something with a similar sized signature, say an insect, since the airplane moves at 1000knots instead of 1, but you have to be able to see it through the noise. That's tricky. If you use a radar like this (high power, really narrow beam) you might be able to see a stealth plane. But, you'd have to know where to point it. Therein lies the challenge.
- josephhardin 14y agoAs someone in the field, the only thing that really stood out about this radar was it's incredibly small beamwidth(.22 degrees compared to a normal .8-1 for most weather radars), and it's incredibly small range gates(.5 meters compared to the 20 meters my radar operates at). That having been said, if this isn't a dual polarization radar, which it sounds like it isn't, then this is still significantly behind the state of the art. The trend has been to move to higher frequency, lower power radars at X, Ku, and Ka band. Also modern weather radars transmit both H and V polarizations allowing us to measure the shape of the raindrops as well as retrieve full drop size distributions. See http://www.casa.umass.edu/main/research/ http://www.casa.umass.edu/main/research/ and http://pmm.nasa.gov/science/ground-validation/D3R http://pmm.nasa.gov/science/ground-validation/D3R as examples of newer systems.
- tazzy531 14y agoIs this a "bug" that is being marketed as a "feature"? It's great that you can see individual raindrops, but with radar, I'd think you'd want to filter the raindrops out.
- ceejayoz 14y ago> It's great that you can see individual raindrops, but with radar, I'd think you'd want to filter the raindrops out. Article says it was developed to spot stuff falling off the Space Shuttle during launch, so no.
- ck2 14y agoSo why are we spending all this money on "stealth" fighters if essentially other advanced countries like Russia can certainly have similar technology.
- retr0rocket 14y agobecause there's other countries then russia
- ck2 14y agoThat Russia and China doesn't sell their radar to? Name one? Stealth is just more dollars for the industrial war complex, especially if they are just going to switch to an army of remote control drones now. Let's swap the military and NASA budgets for just one year.
- huggyface 14y agoNeither Russia nor China tend to sell their latest hardware.
- MichaelApproved 14y agoIt bugs me when I see this. Neil deGrasse Tyson is asking to double NASAs, budget as if that would be the best place to have money spent on science research. NASA was the answer to last century's space race. Throwing money at it is an old, simple solution. I'd love if people came out with more ideas like the x-prize. I can get behind those new ideas. Edit: and it's not like the military doesn't spend a ton of money on scientific and space research
- run4yourlives 14y agoBecause that's how arms race's work. It's how all competition everywhere works.
- tsotha 14y agoWhat makes you think this radar is any good at picking up an aircraft like the F-22?
- BlackNapoleon 14y agoSo this is what they're letting us know about...imagine what they're working on now.