Locate and analyze two news reports of recent astronomical discoveries.

Brief Overview of Activity: Locate and analyze two news reports of recent astronomical discoveries.

Required Items: The internet and/or periodicals such as (for example) The Washington Post or Sky and Telescope

The daily news is not just sports and politics. It includes science too! For this simple activity all you need to do is find two articles related to astronomy (either online or in hard copy), summarize and analyze them.  The topics can be anything of your choosing so long as they are relevant to the course material.  Examples could be a new telescope that has recently come online, the discovery of a new exoplanet, etc.; the idea is for you to find and write up something you are interested in!  The writeup should be roughly one page long (double-spaced); the first half should be a summary of what was discovered, and the second should be your analysis of it–did it make sense?  Was it well-written?  Did it tie into things we’ve discussed in class?  What are some of the ramifications, etc.?   Include the complete citation of the original article (hyperlinked if it is from the internet).  Make sure your sources are reputable ones, whether online or not; if you have any concerns about whether that’s the case or not, please simply contact me and I can give you my opinion.

HR Diagram Activity  (30 points)

Brief Overview of Activity: Use an HR diagram to learn about the differences between the stars in our stellar neighborhood and the brightest stars in the sky.

Required Items: this HR diagram, red & black ink pens.

Procedure:

On the HR diagram, plot each star from the “Brightest Stars Group” in black ink and then plot each star from the “Nearest Stars Group” in red ink.

Data for both groups of stars can be found below.

Describe any differences between the two groups of stars – such as their location on the diagram, color, mass, and the types of stars in each group.

Which of the two groups of stars is most representative of the vast majority stars in the universe?

Data

Nearest Stars Group

Radioactive Dating Activity (due at Stage 2) (30 points)

Brief Overview of Activity: Radioactive decay is one of the sources of the heat that drive the Earth’s geologic activity. Radioactive decay also allows us to date rocks and determine the age of the Earth and other solar system bodies.

Required Items: 36 coins, a calculator, pencil & paper.

Procedure:

In this activity you will simulate the radioactive decay of 36 atoms of a rare isotope of uranium, U-235. Uranium-235 has a half-life of 700 million years. Gather 36 coins and arrange them in a 6 x 6 grid with all of the coins facing heads up.

Flip each coin into the air and then place it back in its original location on the grid. This represents the passage of 1 half-life (700 million years for this example). The coins that came up heads represent atoms that have not yet decayed; the coins that came up tails represent atoms that have decayed. Record the number of heads below.

Next flip each one of the remaining heads-up coins once and place it back in its original location. 1.4 billion years have now passed by (2 x 700 million). Record the number of remaining heads below. Repeat this process until all coins are tails up.

_______ Original number of U-235 atoms

_______ Remaining number of U-235 atoms after 1st flip

_______ Remaining number of U-235 atoms after 2nd flip

Add additional lines as needed.

Questions:

How many half-lives did it take for all of the atoms to decay?

How many years does that equate to?

Do you think everyone in class will get the same answer? Why?

    Sun's diameter in kilometers              image diameter in centimeters
------------------------------------- = ------------------------------------------
 Distance to the Sun in kilometers       distance between image and pinhole in cm

Brief Overview of Activity: Over a period of at least three consecutive evenings, you will make careful observation of the Moon’s changes in appearance and position.

Required Items: a notebook to take notes or make a sketch (bring your red flashlight), you may take digital photos if you wish.

Number of Observations needed: 3

Timing of Observations: 3 consecutive nights, around (and after) sunset, a few days after the Moon is new. Your instructor will inform you what the appropriate viewing days are in the term.

Procedure:

Choose a location with a good view of the western horizon from which you can clearly observe the Sun at sunset. Since we will be timing our observations a few days after the Moon is new, the Moon should be visible in the sky at (and for a while after) sunset. It is important that you make all of your observations from the same location and at the same time. You may want to mark the location with a piece of tape to insure you are observing from the same location each time.

First measurement: This measurement is important. It will be used as a reference point for all future measurements. Arrive a little early and try to find a suitable reference object in the distance near the horizon. Look for a distinctive tree, building, rock formation, or other object. Pick something you will remember and be able to easily spot each time you come to observe. Mark the location and description of your reference object in your notebook.

For Each Observation: Make a note in your notebook about appearance of the Moon and its location in the sky. You may make a sketch if you wish. Note any changes from the previous day’s observation. Be sure to note the location, date, and time of your observations.

Location of Observations: _______________________________________________

Observation (1) Date ____________________Time __________ pm

• Horizontal angular measurement ___________ degrees
• Vertical angular measurement      ___________ degrees
• Appearance _____________________________________________

Observation (2) Date ____________________Time __________ pm

• Horizontal angular measurement ___________ degrees
• Vertical angular measurement      ___________ degrees
• Appearance _____________________________________________

Observation (3) Date ____________________Time __________ pm

• Horizontal angular measurement ___________ degrees
• Vertical angular measurement      ___________ degrees
• Appearance _____________________________________________

Angular Measurement: As shown below, you can use your fingers (or hand) to estimate angles. Using your measured angles, it is possible to determine the angular change in the Moon’s position from day to day. You will need to make two angular measurements for each observation – one horizontal angular measurement and one vertical angular measurement. Your horizontal measurements are made from the reference object/point to the Moon. Your vertical measurements are made from the horizon to the Moon.

Fully extend your arm and use the finger/hand guidelines to make your angular measurements.

Questions: