Latitude and longitude
With passing rain showers and two construction sites up and running from early each morning, I opted to return Binky to the cycad. This worked well enough last summer.
Binky is actually the same model of Binky as was used last term.
Binky was in a quadruple wrap of grocery and hardware bags this summer. The image was taken with the Pixel 7 Pro and then portrait blurring was used to blur out the background frondlets.
The Pixel produced coordinates very close to those of the prior summer, North 6° 54.544', East 158° 09.610'. I noted last summer that North 6° 54.543', East 158° 09.611' might have been closer to Binky. This term I am hoping inclusion of the accuracy will help the students understand the uncertainty in the location.
The morning board was minimalist. Thirty minutes were spent getting GPS essentials downloaded onto Android devices. I then went into the Settings on each device and gave GPS Essentials the location permissions for which the app does not ask. I have no idea why the app does not request the location permssions that the app needs to operate.
One iPhone did not have Compass. I failed to locate Compass inthe Apple app store. The student eventually located and downloaded the app. With no more direction than the above the students set out to "make the numbers match" and find Binky. This term I did not send out nor pull up the GPS Essentials presentation.
At first the students milled around under the covered walkway.
Binky in the rafters would likely be quicklime found.
One student noted that the activity reminded them of Pokemon Go. Eventually the students moved out from under the covered walkway.
The students quickly latched onto the correct coordinates, but on not immediately seeing Binky they moved on.
Back in the classroom I wrapped up with coverage of latitude and longitude.
Then I outlined the plan for the afternoon lab using Google Earth.
This summer the ongoing construction of the new teaching and learning health clinic meant that the route formerly used for finding the conversion factor between arcminutes and meters was still blocked and unusable. The construction fence continues to prevent the use of a line of latitude of sufficient length.
The eastward line
Starting location near the bookstore. Thirty meters was smack dab in the middle of the road but this appears to be unavoidable without using a different distance.
I wound up needing two devices in the field. I needed to keep GPS Essentials open on the tablet because the app loses its location when not in the foreground. On my phone I ran the following spreadsheet to record data handle conversions for the measuring wheel.
At least 60 meters was shady. I had discovered at 30 meters that the spreadsheet was set up wrong for this run. The spreadsheet was set up for the covered walkway and was converting feet to meters, not meters to feet. I needed a meters to feet conversion. The tablet was unable to connect to WiFi from the 60 meter mark, so I had to rely on the phone for online work. The Pixel still had WiFi connectivity at 60 meters.
150 meters just landed on the far side of the entrance drive.
This line works well and will likely work better when the barrier comes down. The line well exceeds 0.100 arcminutes which is a plus over the older lines. The route is not particularly wet - a problem with the line off of the gym.
Back in the classroom I pulled up Google Earth again and sketched what we had done and why out in the field. I then reflected this sketch onto the whiteboard.
The walk would end with a final 240.5 meter measurement at the construction barrier.
OpenDEM suggests that the actual value is 1841.85 meters per arcminute. 1826.35 meters per arcminute is within one percent of the expected value.
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