What’s Way Out There?

Big Idea: The Hubble Space Telescope image “Hubble Ultra Deep Field” shows a variety of objects in the very distant Universe that can be systematically and scientifically counted, organized, and classified.

Computer Setup and/or Materials Needed:

a) Access to the image at: http:// www.spacetelescope.org/images/heic0406a/ That originated from http://www.spacetelescope.org/news/html/heic0406.html

b) Access to the SkyWalker website at: http://www.aip.de/groups/galaxies/sw/udf/swudfV1.0.html

c) Note: There is no expectation that students have studied galaxies prior to completing this research project.

Phase I: Exploration

1) Access the online Hubble Space Telescope Image at http:// www.spacetelescope.org/images/heic0406a/ You might be able to make it larger and smaller by “left clicking” on the image with your mouse. Most of these objects are galaxies far, far from Earth. However, a few objects are nearby stars, as indicated by “four points” on the image, like shown at left.

How many stars can you find? Seven

2) 2. Again, most of these objects are not individual stars, but actually distant galaxies—isolated collections of millions or billions of stars that look like a tiny dot or cloud. Determine how many galaxies are found in the image. One strategy to count the number of galaxies in the image is to just count the number of objects in ¼ of the image (the bottom left corner for example) and then multiply the number of galaxies times four to get the total number. Total number of galaxies in this image? Ten Thousand

3)Some of the galaxies are orange-red in color, while others are white, and others are blue. What is the most common color of galaxy in the image? The most common color I noticed was Blue, the color of galaxies are determined by the types of stars found within the Galaxy. These lights pass through many filters therefore changing colors so the colors we are seeing in the picture might not be the galaxies true color.

3) If we assume that all of the galaxies in this image have the same diameter, the ones that are close appear larger and the ones that are more distant appear smaller. Are most of the galaxies in this image relatively near or relatively far? What is your evidence?

The Galaxies that appear larger are closer to the telescope than the galaxies that appear smaller in diameter and are not well defined. The electromagnetic spectrum of light includes radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, and gamma rays.

Slater, Timothy F., Roger Freedman. Investigating Astronomy: A Conceptual View of the Universe, 2nd Edition. Bedford/Freeman/Worth, 05/2014. VitalBook file.

The citation provided is a guideline. Please check each citation for accuracy before use.

Phase II – Does the Evidence Match a Given Conclusion?

4) Access the interactive Ultra Hubble Deep Field site through the the SkyWalker website at: http://www.aip.de/groups/galaxies/sw/udf/swudfV1.0.html

The green circle in the top left hand corner is a sort of “magnifying glass” that you can drag around that will let you look at close up portions of the Hubble Ultra Deep Field. Note that the picture is about 8 green circles wide and 10 green circles tall, for a total of about 80 green circles over the whole image.

Make rough sketches of the five closest galaxies you can find in the image. [pic] [pic] [pic] [pic] [pic]

If a fellow student proposed a generalization that “nearby galaxies are equally split between circular-round and elongated spiral shapes,” would you agree, disagree with the generalization based on the evidence you collected? Explain your reasoning and provide specific evidence either from the above tasks or from new evidence you yourself generate using the SkyWalker Web Site. Reasoning: I would have to disagree out of the five closest galaxies only one was elongated shape. Most of the Galaxies seen in the picture are circular shaped when seen through a telescope, or in other words the galaxy is an elliptical galaxy. The most common galaxy I see are Spiral Galaxies, which has spiraling arms of stars and dust coming from the center of the galaxy.

Phase III – What Conclusions Can You Draw From This Evidence?

The Hubble Ultra Deep Field is one of most important images in astronomy because it shows some of the most distant galaxies in the Universe. What conclusions and generalizations can you make from the following data collected by a student by randomly positioning the green circle in an effort to determine WHAT IS THE GENERAL DISTRIBUTION OF GALAXY COLORS? Explain your reasoning and provide the specific evidence you are using, with sketches or pie charts or graphs if necessary, to support your reasoning.

|GREEN CIRCLE SAMPLE NUMBER |NUMBER OF RED-ORANGE GALAXIES |NUMBER OF BLUE-WHITE GALAXIES |
|1 |7 |27 |
|2 |10 |16 |
|3 |15 |19 |
|4 |10 |29 |
|5 |12 |27 |

Data collected at http://www.aip.de/groups/galaxies/sw/udf/swudfV1.0.html

5) Evidence-based Conclusion: Reasoning: The Blue regions are filled with many young stars. High-mass stars live fast and die young, using fuel at a high rate to maintain high temperatures. This causes them to emit hot radiation, which is blueish. So in this picture there is a numerous amount of young galaxies compared to the Red-Orange Galaxies which is a old mass of stars that have swollen and cooled emitting cool radiation which is reddish-orange.

Phase IV – What Evidence Do You Need To Pursue?

Imagine your team has been assigned the task of writing a news brief for your favorite news blog about the differences between the numbers of nearby and extremely distant galaxies in the Universe. Describe precisely what evidence you would need to collect, and how you would do it, in order to answer the research question of, “Are there more nearby galaxies or extremely distant galaxies?

6) Create a detailed, step-by-step description of evidence that needs to be collected and a complete explanation of how this could be done—not just “move the green circle around and look at how many big and how many small,” but exactly what would someone need to do, step-by-step, to accomplish this. You might include a table and sketches-the goal is to be precise and detailed enough that someone else could follow your procedure.
I would discuss the Redshift relationship, this states that an astronomical object is moving away from the observer. To determine a galaxy's distance, we must rely on indirect methods. For example, one assumption made by Hubble an earlier 20th century astronomer, and other early 20th century astronomers, is to assume all galaxies of the same type are the same physical size, no matter where they are. This is known as "the standard ruler" assumption. To determine the distance to a galaxy one would only need to measure its apparent (angular) size, and use the small angle equation: a = s / d, where a is the measured angular size, and d is the distance to the galaxy.

Phase V – Formulate a Question, Pursue Evidence, and Justify Your Conclusion
Your task is to design an answerable research question, propose a plan to pursue evidence, collect data using the interactive Ultra Hubble Deep Field site (or another suitable source pre-approved by your lab instructor), and create an evidence-based conclusion about the characteristics of galaxies in our Universe, which you have not completed before.

Research Report:

7) Specific Research Question: How did the Hubble change the way Astronomers view distant galaxies?

8) Step-by-Step Procedure, with Sketches if Needed, to Collect Evidence: One of the main scientific justifications for building Hubble was to measure the size and age of the Universe and test theories about its origin. Images of faint galaxies give 'fossil' clues as to how the Universe looked in the remote past and how it may have evolved with time. The Deep Fields gave astronomers the first really clear look back to the time when galaxies were forming. The first deep fields – Hubble Deep Field North and South – gave astronomers a peephole to the ancient Universe for the first time, and caused a real revolution in modern astronomy. The observed region of sky in Ursa Major was carefully selected to be as empty as possible so that Hubble would look far beyond the stars of our own Milky Way and out past nearby galaxies. Almost 3000 galaxies were seen in the image. Scientists analysed the image statistically and found that the HDF had seen back to the very young Universe where the bulk of the galaxies had not, as yet, had time to form stars.

9) Data Table and/or Results (use additional pages if needed): Deep imagery from Hubble, has revealed the most distant galaxies ever observed. The time it has taken their light to reach us, some of the galaxies are seen just as they were just half a billion years after the Big Bang. The idea orginated from images taken in 1993 after the repair of the Hubble, the image contained many galaxies that were not able to be seen by conventional ground telescopes. These very remote galaxies also seemed to be smaller and more irregular than those nearer to us. This was taken as a clear indication that galaxies form by gravitational coalescence of smaller parts.

10) Evidence-based Conclusion Statement: Arches Cluster is the densest known star cluster located in the Milky Way, Arches Cluster is located about 25,000 light years away from earth in the constellation of Sagittarius close to the heart of the Milky Way. A fairly young astronomical object Arches cluster is between two and four million years old. Arches Cluster is so dense that in a region equal to the distance between the Sun and its nearest star there would be over 100,000 stars. One-Hundred and Fifty of the stars within Arches Cluster are among the brightest ever discovered in the Milky Way. These bright stars are so bright and massive they will burn their fuel within a short time, just a few million years and die in a supernova explosion. Even though Arches Cluster is extremely bright, the Cluster cannot be seen with the Naked Eye, The Visible Light from the Cluster is being blocked by clouds of dust in the region. Astronomers have to use detectors that can collect light from x-rays, infrared, and radio bands as these wavelengths can pass through the clouds of dust. Arches Cluster is considered to be the “most crowded place in the milky way.

Phase VI – Summary PRINT YOUR NAME: WILLIAM RAINES

11) Create a 50-word summary, in your own words, that describes the characteristics and distribution of galaxies in our Universe. You should cite specific evidence you have collected in your description, not describe what you have learned in class or elsewhere. Feel free to create and label sketches to illustrate your response.

Elliptical Galaxies are made up of very little gas and dust. Since gas and dust are found in clouds which are the birth place of stars, more than likely there will be very few stars in an elliptical galaxy. Elliptical Galaxies contain primarily old res stars, which can also be called Population II stars.

Lenticular Galaxies have centers that bulge and disks, with no spiral arms, Irregular Galaxies are categorized as to fit into either spiral or elliptical classes. These types of galaxies have a variety of shapes and characteristics. Irregular galaxies are usually the result of collisions between galaxies or gravitational interactions between galaxies.

Galaxy Spectra clearly shows you whether a galaxy contains star-forming regions called HII regions. HII is a spectral emission line that corresponds with ionized Hydrogen. HII regions are areas of the galaxy that hydrogen nuclei and electrons are recombing to create neutral hydrogen.

"Galaxy Spectra." Galaxy Spectra. 2 Jan. 2010. Web. 7 Jan. 2016.