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Lab 1: Where Am I?


There are lots of interesting and historic places in Greenwich, there are also some places that are fairly ordinary. Working in your lab groups (see below) you will locate one such ordinary place, determine where it is a couple of different ways, measure the shortest distance from that point to the Prime Meridian, and note some additional physical markers.

Figuring-out where you are and how far it is to other things is the first step in mapping the world around us. This lab is designed to give you first-hand experience with some of the tools and processes to do that measuring and mapping.

Once you have completed the data collection in Greenwich you and your lab partners will analyze the data and describe the results in a lab report which will be due next week.

Make sure that at least one person in each lab group brings a laptop with them to Greenwich. It will make some aspects of the lab much easier. If you have a minute to install Google Earth before tomorrow that would be even better.

Lab Groups

Listed below are your scientifically chosen lab groups along with a description of the fairly ordinary place you will need to locate.

  • Red: Lily, Bill, Emily - The steps leading from the sidewalk to the front entrance of the Our Lady Star of the Sea church.
  • Green: Krystnell, Johanna, Spencer - The intersection of May's Buildings Mews and May's Court.
  • Yellow: Mamus, Ivan, Vivian - The distal end of Croom's Hill Grove.
  • Black: Eva, Gillian - The steps leading from the sidewalk into the courtyard of the museum devoted to cooling oneself.
  • Purple: McKayla, Ben - On the sidewalk near the marque of the home of Greenwich's thespians.


Once you have located your spot you will need to:

  1. Determine the latitude at that spot using at least three different tools/methods.
  2. Determine the longitude at that spot using at least three different tools/methods.
  3. Determine the elevation at that spot using at least three different tools/methods.
  4. What is due North of that spot? (E.g. "a house with blue shutters", or "an oncoming car...")
  5. What is due South of that spot?
  6. Determine the minimum distance in meters from that spot to the Prime Meridian using at least two different tools/methods.

Hint: There is a really big, sort of blue/green, local reference point for elevation running alongside Greenwich.

Tools and Methods

There are a number of different ways you can determine latitude, longitude, elevation and distance:

  • A well reasoned and reasonably accurate estimate.
  • Measuring by angle of elevation and distance.
  • Measuring by calibrated human pace.
  • GPS device (I have two to loan for 1 hour time blocks on Saturday when we're in Greenwich)
  • Google Earth

Each of these tools has their own strengths and weaknesses, sources of error, etc. One aspect of this lab is to learn what they are and how to best work with them. At least one person in each group will need to install Google Earth on their laptop.

Note that not all of the tools/methods need to be employed while you are in Greenwich, that is once you have a handle on the spot you could sit at FIE and use Google Earth. All of the other tools/methods require your physical presence at the spot to employ them.


Each group will write-up a lab report in the Lab Notebooks section. There is a very simple template there for each group to start with. Your write-up should include:

  • A description of the task at hand and your approach to the work.
  • A description of the spot you are working from.
  • The measurements as listed under Details above, for each of the tools/methods, organized in tabular form.
  • A discussion of the sources of error associated with each of the tools/methods you employed and the likely range into which the correct answer is likely to fall for each of them.
  • The raw data, that is each value read (at minimum 3 values for each data point) for each tool/method you employ for a given measurement.

Extra Credit: A basic visualization which utilizes an aerial image with a placemark at the spot, labeled with the coordinates, and visual indications of the "zone of error" for each of the tools/methods you employed.

Neatness and organization count, significantly.


Once you folks begin working on the lab I will be available to answer questions, loan tools, make smart remarks, etc. You can find me at roughly 51.4816 -0.0099, probably drinking coffee.