Don York checked on how the students did yesterday selecting galaxies and recording data. Since they are working with greater speed (very smart, computer-savvy students), Don suggested they collect additional data that will allow them to calculate the mass of the galaxies they selected. This led the teachers into additional questions that then led to further learning and discussion. Again, the theme of how much our understanding of the Universe is changing so rapidly.
I can’t help but get excited about astronomy and astrophysics. If I were a young student of science today, I would give very serious consideration to a career in this field. Of course, following leading-edge science and technologies has been a dominant factor in my choice of career moves over the years, including the fields I choose to learn more about as a science teacher. This fascination translates as enthusiasm about STEM (Science, Technology, Engineering, and Math) education and STEM careers I tell my students about.
Today’s lesson focused on X-ray astronomy. Like gamma ray astronomy, this is a fairly new area of study. It has only been about 10 years since x-ray images contain sufficient definition to be able to observe the spectra of heavy elements in fairly clear images. Micro calorimeters hold promise for even greater resolutions in the future.
Tomorrow should be interesting as students plot the data they’ve collected the past two days, and try to interpret results into conclusions they can make about the nature of galaxies, classify them as blue or red, calculate the population of stars in the galaxies, and the total mass of protons and neutrons in the galaxies. It should provide students with a real insight into the wealth of information that can be gleaned from spectral data.
So, you ask, “What happened to days 2 – 5?” Actually, I had to take a brief hiatus those days for a destination engagement. Please don’t ask. Suffice it to say it involved a trip to the west coast, the Redwood Forest is a strange place to propose, and that the “hills” in San Francisco are murder on an arthritic hip! But my son is finally engaged to the love of his life.
I have a lot of catching up to do. This program runs at a near manic pace, and is flexible enough to change and evolve with the students’ interests and questions. Missing four days means that what I knew to be the plan last Monday has changed, and I’ve got to get with the program.
Today, Don introduced students to magnitude, spectra and red shift so that they can do a project in the Sloan Digital Sky Survey, Data Release 9 (SDSS DR9). The object of their project is to discover the nature of galaxies. I could tell you more about what we hope they’ll come to realize, but that would spoil the fun when they do.
For me, it was a great day of new learning. I was introduced to and used SDSS Data Release 7 several summers ago when I participated in the Capstone program here with four of my students. They chose to investigate how nicely structured spiral galaxies eventually become the red smudges called elliptical galaxies. Data Release 9 is the most recent release, and contains more refined data. Today, I learned that these two galaxy classifications, spiral and elliptical, are being used less as astronomers find there are many more types of galaxies. The digitalization of images is revealing a lot more about astronomical objects than photographic images ever could, so what we thought we know about the Universe is changing rapidly. This goes right to the heart of the nature of science, that what we scientifically know is tentative, only to be revised or changed as our ability to observe, analyze and infer improves.