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Picard Kills Kirk
04-05-2009, 02:36 PM
If you follow this link...

http://www.google.com/maps?f=q&source=s_q&hl=en&geocode=&q=handle+rd+and+south+ellicott+highway,+colorado&sll=38.823945,-104.381142&sspn=1.596252,2.471924&ie=UTF8&ll=38.827874,-104.36574&spn=0.049881,0.077248&t=h&z=14&iwloc=addr

...It will take you to Colorado. To the right of where the map is centered there are some strange circles designs on the ground. Did I stumble upon the world's largest crop circle? What are these circles? I should also mention I don't know anything about farming.

MikeS
04-05-2009, 02:38 PM
Center-pivot irrigation. (http://en.wikipedia.org/wiki/Center_pivot_irrigation) You can see the boom in most of the circles; in this one (http://www.google.com/maps?f=q&source=s_q&hl=en&geocode=&q=handle+rd+and+south+ellicott+highway,+colorado&sll=38.823945,-104.381142&sspn=1.596252,2.471924&ie=UTF8&t=h&ll=38.833874,-104.356685&spn=0.010664,0.016501&z=16), for instance, it's at about "nine o'clock" on the circle.

MikeS
04-05-2009, 02:45 PM
Missed the edit window the above link to the detail of the boom doesn't work. Try this one (http://www.google.com/maps?f=q&source=s_q&hl=en&geocode=&sll=38.823945,-104.381142&sspn=1.596252,2.471924&ie=UTF8&t=h&ll=38.833874,-104.356685&spn=0.010664,0.016501&z=16) instead.

Picard Kills Kirk
04-05-2009, 03:00 PM
Incredible. I have never heard of or seen anything like this before.

Thanks, MikeS.

Sam Stone
04-05-2009, 03:22 PM
You can see these all through southern Alberta. Have a look at this map: Google map of some southern Alberta irrigation (http://www.google.com/maps?f=q&source=s_q&hl=en&geocode=&q=handle+rd+and+south+ellicott+highway,+colorado&sll=38.823945,-104.381142&sspn=1.596252,2.471924&ie=UTF8&t=h&ll=49.780599,-112.437172&spn=0.187549,0.217323&z=12&iwloc=addr).

The advantage is mechanical - if you need to irrigate, you either do this, or you build giant rolling sprinklers that traverse the crop. Having a pivoting sprinkler arm is easier to do. The drawback is that you lose the area of the field between the circle and the rectangular boundary of the land.

DSYoungEsq
04-05-2009, 07:22 PM
You can see these all through southern Alberta. Have a look at this map: Google map of some southern Alberta irrigation (http://www.google.com/maps?f=q&source=s_q&hl=en&geocode=&q=handle+rd+and+south+ellicott+highway,+colorado&sll=38.823945,-104.381142&sspn=1.596252,2.471924&ie=UTF8&t=h&ll=49.780599,-112.437172&spn=0.187549,0.217323&z=12&iwloc=addr).

The advantage is mechanical - if you need to irrigate, you either do this, or you build giant rolling sprinklers that traverse the crop. Having a pivoting sprinkler arm is easier to do. The drawback is that you lose the area of the field between the circle and the rectangular boundary of the land.

Which is 4r2 - ᴨr2, or 4 - 3.1415926... so somewhat less than 25% but more than 20%. Not an insignificant amount, in other words.

Moonshiner
04-05-2009, 07:57 PM
Modern center pivot systems can have corner fill systems. They're complicated and expensive, so the payback may be questionable depending on crop.

http://www.zimmatic.com/#/Products/CornerSystems/Maxfield/

Chronos
04-05-2009, 08:03 PM
Having a pivoting sprinkler arm is easier to do. The drawback is that you lose the area of the field between the circle and the rectangular boundary of the land.But then, in most of the western US, land is very cheap, and it's just the water itself and the delivery method that's expensive. So wasted land that isn't getting watered isn't really a big deal

Gorsnak
04-06-2009, 12:31 AM
Which is 4r2 - ᴨr2, or 4 - 3.1415926... so somewhat less than 25% but more than 20%. Not an insignificant amount, in other words.

Actually it will be less than 20%. Even if you don't go with the expensive articulating dealie, there's an end gun with a range of a couple hundred feet that shoots into the corners.

Cyberhwk
04-06-2009, 03:20 AM
There EVERYWHERE (http://www.google.com/maps?f=q&source=s_q&hl=en&geocode=&q=kennewick,+WA&sll=38.913994,-104.568193&sspn=0.010886,0.027895&ie=UTF8&ll=46.314687,-119.039955&spn=0.30922,0.892639&t=h&z=11) around here.

Cyberhwk
04-06-2009, 03:37 AM
They're... :smack:

DSYoungEsq
04-06-2009, 06:55 AM
Actually it will be less than 20%. Even if you don't go with the expensive articulating dealie, there's an end gun with a range of a couple hundred feet that shoots into the corners.

Does it water outside the edges of the field? Or is the radius of the arm shorter than half the length of the side?

sailor
04-06-2009, 07:03 AM
Does it water outside the edges of the field? Or is the radius of the arm shorter than half the length of the side? I assume it is controlled in such a way that it shoots only into the corners and stops shooting when pointed at the side. It would not be difficult to have a controlled pressure which increases to a max when it gets to a corner and decreases gradually to zero when at the center of a side.

notfrommensa
04-06-2009, 02:51 PM
Can't farmers grade the fields so the corners are in low spots so water gravitates to the corners?

Philster
04-06-2009, 02:57 PM
Not practically.