Got back last night after a week long trip to Ecuador. Fantastic trip! The main purpose was a wedding, a friend's son married a local girl. The bride's father spent at least 1/2 million on this wedding, I felt like I was at a Hollywood wedding. He also paid for several day long tours for everyone from out of the country.
Mitad Del Mundo was really cool. They have a very large monument at the place where they THOUGHT the equator was:
I assume it is in error (240 meters south) due to being based on astronomic observations.
And the "new" location, by GPS. Not sure how they did the GPS (static, handheld, datum, etc):
At this site they did a few cool demonstrations. If you put a sink right on the line, the water goes straight down. 10' either way (N-S), it swirls, in opposite directions.
Also, they had me do the "DUI test", walk a straight line with my arms out and eyes closed. Impossible to do on the exact equator, but easy to do off of it. So don't ever get pulled over on the equator!
One of my graduate students (in the middle 1990s) told me he did the observations back in the late 1980's with a Trimble dual-frequency receiver as part of a class project when he was an undergraduate in Quito. (At the time, he was with the IGM; Instituto Geografico Militar.)
Notice that in the photo of the equatorial monument everything is sideways. That's because at the equator, up is to the side, and everything sticks out sideways from the earth. Just look at any globe and you'll see what I'm talking about.
I'm surprised that a few feet makes so much difference on the water. Wouldn't the Coriolis effect be about proportional to the sine of the latitude?
And do you have any theory on the DUI test? It just doesn't make sense to me. You mostly depend on gravity to tell which way is up. The only thing different is the Coriolis effect. If you can walk on either side of the equator what is special about being on it?
I am guessing the Mitad Del Mundo was built before they invented the kitchen sink since the water in the sink would have told them they were not on the equator.:-)
Seriously, do you know when it was built?
James
I would guess 1960's from seeing the interior.
You beat me!
I had been planning a trip to Quito for this September but due to some unexpected expenses the trip is postponed to 2013. I recently finished reading two books about the French/Spanish expedition in the 1700's to determine the length of a degree of Latitude near the equator. It was to be compared to measurements in France and the Arctic Circle to determine if the earth was flattened at the poles. The two books were: The Map Maker's Daughter and Measure of the Earth. The second book was the most informative and in depth.
One of the places I would like to see when I go is the top of Cataquilla Mountain. There are some ancient ruins there that are right on the equator. It is located at
0° 0'0.60"N and 78°25'41.09"W.
As to the tricks you observed, you will find the explantions on the internet. I read about them while researching for my trip.
Glad you enjoyed your trip. How was the weather? Did you fly into the new airport? The runway is located on part of the baseline layed out during the expedition. There is supposed to be a small hut that can be seen as you land that is at one end of the baseline.
I visited Ecuador compliments of the US Navy many moons ago. I became very familiar with the location of the equator even though it was well before my surveying career. I am forever after that "incident" a Shellback, laughing and cursing at the scaly Pollywogs of the world. I don't imagine that a ceremony similar to what I underwent occured on a commercial airliner on the trip down, or at least I hope not. Very nice folks in Ecuador.
"If you put a sink right on the line, the water goes straight down. 10' either way (N-S), it swirls, in opposite directions."
Sorry - not buying that...
I have video of the sink on the line and at each side. I will post a link to it.
As soon as I saw it I thought that would be a great way to determine exactly where the equator was!
this is just a guess-but I think they may have determined the location of the equator previously using IAGS triangulation based on PSAD56 datum (i.e. La Canoa datum). It was based on an astro position at La Canoa, Venezuela. So the combination of inaccuracies in astro position and the distance through the triangulation network caused the 240 meter error.
You beat me!
The new airport is not yet open. I believe October is the target. It is pretty far away from the city compared to the old one, but I can see why they need the new one. The old one is right in the city, surrounded by houses.
The wedding was just east of the new airport. The road to get there was no super highway, but it was being improved.
The next thing I want to do down that way is the Inca trail from Cuzco to Machu Pichu, or the other place more recently found (I forget the name right at the moment). Last time I was there I took the train (there is no road). I wanted to go this year, but I am taking a medicine for 1 year that reduces my hemoglobin, making it harder for my blood to carry enough oxygen. I will be done in december. Actually my normal hemoglobin level is higher than a normal person (not sure why-hereditary?). it is now at the low end of a normal male.
Fortunately there is always Te de Coca. Much easier to get in Cuzco than Quito. I guess because Cuzco is a lot higher. In Peru it is only legal above a certain elevation. You can either drink it in tea or just chew the leaves.
Jim-if you go there be sure to somehow get on a Chiva, which is an open bus that cruises around town with a DJ or band and lots of alcohol. You wear a cup tied around your neck, and they keep filling it up with some kind of warm alcohol drink.
My daughter:
At least the sign appears to be on a portable base...
Urban Legend
A couple of links:
http://www.snopes.com/science/coriolis.asp
http://www.ems.psu.edu/~fraser/Bad/BadCoriolis.html
That last one is to Penn. State
They talk a little about "tricks" for the tourists at the Equator.
Loyal
Do you remember how it was done? point positioning? What datum? PSAD56?, SAD69? WGS84? There wouldn't have been any CORS back then.
Back then, I'd guess WGS84 with respect to IGN Hqs in Quito.
If anyone is interested in seeing all the pics I took, go to
I am still in the process of uploading. I will also be uploading my pics from Italy last month, lots of photos at Pompeii.
> I'm surprised that a few feet makes so much difference on the water. Wouldn't the Coriolis effect be about proportional to the sine of the latitude?
>
> And do you have any theory on the DUI test? It just doesn't make sense to me. You mostly depend on gravity to tell which way is up. The only thing different is the Coriolis effect. If you can walk on either side of the equator what is special about being on it?
Ditto to Bill's comments and observations. I'm guessing the demonstrations may just be part of the tourist attraction.
EDIT: THANKS FOR THE LINK LOYAL:
FROM LINK:
Is it possible to detect the Earth’s rotation in a draining sink?
Yes, but it is very difficult. Because the Coriolis force is so small, one must go to extraordinary lengths to detect it. But, it has been done. You cannot use an ordinary sink for it lacks the requisite circular symmetry: its oval shape and off-center drain render any results suspect. Those who have succeeded used a smooth pan of about one meter in diameter with a very small hole in the center. A stopper (which could be removed from below so as to not introduce any spurious motion) blocked the hole while the pan was being filled with water. The water was then allowed to sit undisturbed for perhaps a week to let all of the motion die out which was introduced during filling. Then, the stopper was removed (from below). Because the hole was very small, the pan drained slowly indeed. This was necessary, because it takes hours before the tiny Coriolis force could develop sufficient deviation in the draining water for it to produce a circular flow. With these procedures, it was found that the rotation was always cyclonic.
Thanks for the photos John. They gave me a bit of a preview for my planned trip to Quito next year.
