An astronomer has a goal to discover and understand the nature of objects in our universe. Astronomers analyze and interpret the information obtained in order to make accurate models of these objects using instruments that collect, record, disperse and magnify the light that celestial objects give off. In this laboratory I learned how to measure the altitudes of stars using a quadrant. A quadrant is a quarter of a circle that has been divided into 90 degrees. I also learned how to find the angular diameters of the Sun and Venus. We used the calibration bar to find the scale of the ruler; image scale calibration is a task astronomers perform routinely. To find the scale you divide the bar length in degrees by the bar length in ruler units. In the diagram on page 2 of the lab the calibration bar is four units long, so each unit is one-quarter of a degree. We then measured the diameter of a lunar crater using the same method. The crater studied was called Ptolemaeus. After measuring the diameter of a lunar crater we compared the diameter of the Earth’s shadow with the Moon’s diameter. I then learned that the Earth’s shadow is 3 times larger than the Moon’s. We then measured the angular diameter of Jupiter and the angular distance between the Moon and Venus. After that we compared the brightness’s and colors of stars. The two brightest stars were the beta Ori and alpha Can Maj. We then explored the colors of stars in a distant galaxy. The tool we used to find dominant colors was called the Color Meter. As I moved the Color Meter around the galaxy the dominant colors varied. After having this lab I learned a lot about different things in the Universe. It made me understand more of an astronomer’s job and the certain tools they use to figure out different measurements of things in the universe.