Physics homework help. Physics homework help.
Exploration Study and Information
1. Exercise: Constellation Observation Portion
- Print out five (5) copies of the Constellation Observation form (Points will be lost if you do not use the forms provided)
- A Constellation map/chart (for the correct current season) options: you can use the Appendices in our eText; you can use the freeware, Stellarium program; a phone app; you could use the star map found in the center of a current issue of “Astronomy” or “Sky and Telescope” magazine; or find your star map online. We suggest that you do not buy the plastic circular devices called a planisphere; they are too small and, as a result, too distorted. But they can be used in a bind.
- Flashlight (see below for advice)
- If you live in the heart of a light-polluted city you may have to find a safe location away from the city. Identifying constellations is easier if you select a clear, moonless night and get as far from city lights as possible. Always try to have someone to accompany you, never go to a dark location on your own!!
- Scanner or digital camera
Background Information and Example:
In this lab you are going to be observing the Big Dipper which is part of Ursa Major, along with 4 other constellations (that have 4 or more stars in the outline). Depending on the semester and time of year your constellations for that season will vary. Please use our discussion on Constellations as a starting point.
It will help a lot if you can get away from the city lights as far as possible and on a night when the moon is not up.
For this lab you can use an app or print out sky charts, etc. to help you find your constellations. But no matter which method, you want to be sure that once you find the constellation you are looking for, you put your reference aside and draw what YOU personally see in the sky. To look at your charts use a flashlight covered with several layers of paper or red plastic wrap so it not too bright. That way you will not destroy your night vision every time you turn it on.NOTE: you never want to be outside of your yard in a dark area alone. Always go with a friend or family member and be safe!
Here is an example observation:
Dec. 1, 2013
Location (city & latitude/longitude)
Denver, 39 degrees N, 104 degrees W
Official name of Constellation
Big Dipper, within the constellation Ursa Major
DRAWING: (Includes angular separation measurements and altitude of lowest star coming from the horizon and direction you are facing.)
Depending on the time of year you will not see The Big Dipper as it is shown above, it will appear lower or higher at times and will “tilt” so that the cup is up, down or sideways. It will always be in the North.
Although you can do this lab in one night, it would be great if you can go out over a period of a few weeks at nearly the same time each night and see how the constellations will change as they appear to travel across the sky.
Follow the Procedures below and also be sure to read the General Lab Instructions and the Constellation Observation Rubric so that you know what is expected for this observation project.
- Please study the Constellation Observation Lab Example above.
- You will need to identify the Big Dipper along with four other constellations from your backyard or some other safe location (do note that the Big Dipper is just part of Ursa Major). **You must pick a constellation that has more than 4 stars in its outline.
- You must use the observation sheets provided for this activity and all drawings should be done in pencil.
- NOTE: You can make all of your observations on the same night, given that you can see the full constellation outline and it is not blocked by clouds, horizon, etc.
- Use your Constellation map/chart to find your constellations. The instructions that come with the sky map in the centers of “Astronomy” and “Sky and Telescope” magazine are very clear. Read and follow them carefully and this task will be easier. Once you find your constellation put your resource down. Only draw what you see with your naked-eye.
- For each constellation observation you are required to:
- Fill in the data at the top of the sheet. Be sure to record the exact date/time/location, etc. that you are observing that particular constellation.
- Note the direction you are facing and write that at the bottom of your sheet. (See below for more information.)
- Draw the outline of the constellation just as you see it, tilt and all. Indicate which stars are brightest by making them bigger dots.
- Label the angular separations between each pair of stars in the constellation.
- You will also include the altitude of the lowest star of your constellation. (See example above and below for more information.)
- Refer to General Lab Instructions about how to Submit your Constellation Observation Sheets
Advice on Observing
Always being as safe as possible, it is helpful to pick the darkest section of your observation site and make an extra effort to block out stray light. You could construct a three-sided wall made out of cardboard to block out light as well. Try to make the immediate area around your site as darkened and non-reflective as possible. Use existing structures and foliage to block the direct view of lights. Here is another helpful site: http://www.stormthecastle.com/telescopes/star-gazing.htm
Estimating the Altitude of the Lowest Star in your Constellation
Important: any measurement on your observation should be done by hand and not come from an application/program, etc., otherwise points may be lost.
To measure altitude of a star, simply use your fists. (The average fist from knuckle to knuckle is 10 degrees, and one outstretched finger will be 1 degree, two fingers 2 degrees and so on.) Start by holding one fist out in front of you with your arm fully stretched out like you are holding a vertical rope, and your arm and body making a 90 degree angle. This allows for the bottom of your fist to be “sitting” on the horizon in front of you. (From top to bottom, a fist at arm’s length is about ten degrees on the sky.) Start climbing this imaginary rope with one fist over another, touching. Count the number of “fists” from the horizon up to the star in your constellation that is nearest to the horizon. So, if you counted 5 fists then your altitude would be 50 degrees, 6.5 fists would be 65 degrees, etc. If the horizon involves trees, buildings or a mountain, estimate where the horizon would actually be if there were no trees, mountains or buildings and use that as the starting point for your measurement. It will be important that you are able to measure the altitude within one fist (~10 degrees).Make sure to review the Explorations in Module 1, especially “Tools for Observing the Night Sky” for additional help.
Measuring Angular Separation
Using the same methods as measuring the altitude, you are going to use your fist and fingers to estimate the distance between the stars (angular separation) along the outline your constellation. You of course will need to rotate your fist and fingers to follow the outline. Just make sure to keep your arm totally outstretched as you do so.
At the bottom of your observation sheet you must specify the direction as N, S, E, W, NE, NW, SE or SW. You can use an app compass for a starting point to get your bearings, or the mountains here in Denver, but your measurement should be your own and not come from an outside source.
2. Exercise: Formal Paper
A minimum four page research paper regarding the topic of Constellations and Stars will be part of the project. The content of the paper must include
- short but detailed summary of the history of how the constellations we have today came to be (giving an example of the history of origin of a few constellations, how were the 88 that we have today determined by the IAU etc.)
- Include the formation of the IAU and how decisions were made regarding constellations,
- also tell us about 2 recent decisions/findings made by the IAU in the past 5 years.
- Based on the constellations you observed, you will also research at least 5 stellar objects that reside in one or more of your constellations, giving a brief summary on each in your own words, including characteristics such as, type, magnitude, location in the constellation and any unique qualities. (Note: these objects can range from stars to nebula to galaxies; do not use information posted in any of our Discussion topics.)
The paper must have an introduction and conclusion, be well organized and have a professional appearance.
The content of thepaper needs to be a least 4 pages (excluding images, tables, etc., quotes should be used at a minimum), in APA format, and it should be double-spaced, with Times New Roman font size 12 and 1-inch margins. Students who plagiarize any portion of their final paper will receive a zero for the entire assignment. Using a paper written for a previous class is not allowed. The in-text citations and reference page should be correctly formatted using APA style. Spelling and grammatical errors will be penalized.