Find a relatively unobscured view of the western horizon. Choose the location carefully so that you will be able to see the sun setting while standing in the exact same spot over the course of the entire semester. To be safe, I’d say that you need an unobstructed view of about 45° on either side of due west. Choose your spot carefully so that it is free of foreground obstacles but has a recognizable background against which you’ll be able to distinguish the location of sunset (a completely flat, featureless horizon will not work; try to have some background objects). You’ll also want to pick a recognizable and reproducible landmark on the ground where you can place your feet each time you do the observation.2. CAREFULLY sketch the horizon for about 45° on either side of due west (which should be in the middle of your drawing). The sun sets in the west, so you want to draw both sides of it. Find due west using a compass and mark its exact location clearly on your sketch. 3. Then mark out azimuth angles in five degree increments on either side of west (so mark 5°, 10°, 15°, 20°, 25°, 30°, 35°, 40° and 45° degrees north of west and the same to the south) using an app that you find to measure angle or ruler held at arm’s length and the fist and finger method to calibrate your perspective. You need to be very careful to have a constant horizontal scale, so take some time doing this. Check the accuracy of your sketch and azimuth labels by measuring the distance between landmarks on the horizon with the fist and finger method and then checking it against what you’ve labeled on your sketch. You will be making all of your observations on this single sketch, so take the time to do it carefully before your first observation. To be safe, go out at least 30 minutes before sunset your first time observing so that you have plenty of time to find a good spot and sketch the horizon.4. Go out again once every week and record the location of sunset on the same sketch. Make sure to record the date and time of sunset each time you make an observation. Keep in mind that sunset times will change significantly over the course of the semester – from ~5:40 PM in January to ~8:00 PM in May. In order to complete this lab, you will need to be free to complete an observation during this interval once per week over the semester. Look up sunset times here: http://www.timeanddate.com/sun/, but record the time you see the sun set, which may differ depending on your location. Do your best to find an unobstructed view of the sunset.