Macho Dark Matter

              Objects included in macho dark matter include white dwarfs, brown dwarfs, black holes, neutron stars and faint red dwarfs. All objects contained in macho dark matter are either the remnants of old stars that have completed their evolutionary cycle or failed stars. White dwarfs are typically about the size of the earth and are formed when a star sheds its outter layers into a planetary nebula. The white dwarf is the core of the star that remains. Brown dwarfs are similar in size to Jupiter and are failed stars. Black holes are about the size of a pinhole and are formed when a supermassive star dies. Neutron stars are about 10 km in diameter and are formed when less massive stars die. Red dwarfs are about half as massive as the Sun and are low-mass stars. All dark macho dark matter is remnents of stars that have completed their cycle so many types of them could be near each other if they were in binary star systems. They are objects that are hard to detect and they are highly massive. They can detect these objects by looking about how objects move. Like objects that orbit something we can not see we can figure out there is mass there. Also they can tell if light bends around another object.

Final Reflection

Sky Journals: My sky journals improved a lot once I learned about Stellarium. Stellarium really helped me know what to look for. It’s really overwhelming to look at such a vast sky and try and pick out shapes that honestly don’t really look like what they’re supposed to look like anyway but I found that knowing what was out narrowed it down a lot and I was able to see the constellations. At the beginning of the quarter I was more concerned with being able to pick out something other than the Big Dipper and I find that I can now pick out quite a few constellations.

Class Reflection: My knowledge since the pretest has improved more than anything.  I really had very limited knowledge at the beginning of the class. I had never taken astronomy so anything I knew already was from previous physics and chemistry classes. Having taken the class I can answer almost all of the questions from the pretest and have a much broader understanding of how the universe works and how we fit into it. The math concepts weren’t too difficult and could be pretty easily explained.

Moon phase lab: This lab gave me a good knowledge of the different phases and when they occur.

Apods:  I enjoyed all APOD’s. The pictures were interesting to look at and the captions were informative.

Research: Telescope research gave me a better understanding of the different types of research. I thought the history researched covered more information than necessary. It was interesting to hear the different myths about why the story behind the constellations. I didn’t really feel like I learned much from the dark matter research that I hadn’t already assumed.  

Celestial Sphere lab: I really disliked this one. I understood how to look for things but I didn’t think it was explained very well how to line things up and how to tell what would appear at a certain location during a specific time of the year.

Scientific methods Lab: Very simple. The math was very familiar.

Sky Journal: They gave me a good, intermediate understanding of what is in the sky and how to look for things. Beneficial for sure.

Weekly Feedback: To be honest I don’t like doing these reflections. I think it’s good that those who aren’t comfortable talking to you in person can tell you this way but I don’t think they should be required and I feel like the things I’m writing on here I have said on my weekly reflections already.

Spectra lab: I liked looking at the different emission and absorption lines from the different elements.

Meteorite Lab and Satellite Lab: I liked these two because they were the most experiment-like. Timing, measuring and doing math are my favorite parts of lab.

Homework from Text: Helped reinforce the math concepts well.

Properties of the Sun: Doesn’t really stand out in my mind much. Maybe that is a reflection on how beneficial it was? I’m not sure.

Star clusters and Age Lab: Simple graphing. I had a hard time answering the questions and drawing conclusions.

Cepheid Yardstick activity: The relationship between the two variables was simple to understand. I liked that.

Stellar Evolution Group project: I didn’t really know what was expected of us when we started the project out and I think that was reflected in our final outcome.

Home Sweet Universe/Art Project: Forced me to research where I am specifically and helped me get the big picture.

Space Exploration/Drake Equation: I discovered that I don’t know what I believe in regards to intelligent life in the Milky Way at all but it was still fun to speculate.

Field trip: It was good to have everything pointed out to me. Perhaps this should happen before the celestial sphere lab?

Sky Journal #10

Date: December 2, 2010
Time: 6:00 PM
Location: Crestview Lane, Mount Vernon, WA

The picture below is a replica I made of the sky as I saw it last night. The points have been drawn fairly large so that they’re able to be seen.
            a. Jupiter: Azimuth: 160⁰ Altitude: 35⁰.
            b. Fomalhaut. Azimuth: 175⁰. Altitude 10⁰. This star is the mouth of Piscis.
            c. The constellation Capricornus: Azimuth: 200⁰. Altitude: 20⁰. I was able to see most of the constellation but couldn’t tell which star was supposed to be the fin of the creature.

Weekly Reflection #9

I didn’t really know much about galaxies prior to this week. I obviously knew the shape of the Milky Way but it was interesting to learn the different shapes that galaxies come in. Learning about Seyferts, Quasars and Blazars was interesting and I our research on MACHO dark matter was pretty simple as we pretty much know the properties of the different types of dark matter from previous chapters. The lab we did as a group was pretty self-explanatory and the math concepts were simple which was appreciated. Lastly, when I was going through different messier objects I thought it pictures were all pretty cool. Our world is pretty beautiful.

Sky Journal #9

Date: November 19, 2010
Time: 9:30 PM
Location: Crestview Lane, Mount Vernon, WA

The picture below is a replica I made of the sky as I saw it last night. The points have been drawn fairly large so that they’re able to be seen.
            a. Fornax: Azimuth: 160⁰ Altitude: 30⁰.
            b. Jupiter: Azimuth: 210⁰. Altitude: 40⁰. I am assuming that this really bright object is Jupiter but it could also be a bright star. I have a hard time telling the difference between the two.

Weekly Reflection #8

The most difficult part for me this week was the labs. I had to skip one of them to go to a corporate meeting and I had difficulty understand the math concepts for both. I think that the actual plotting of the data was time consuming and I realize it can be done on excel but I couldn’t figure out how to overlap both sets of data on the same scatter plot. Aside from the labs I found the lectures to be informative and it was awesome to have a holiday this week! As for the test, I think I did okay on it and I’m sooooo glad that we are able to have notes, it takes away a lot of the stress of memorizing and I think it allows us to think about concepts more when we aren’t worried about memorizing formulas and information. I did think that the test included a lot of writing but with a two hour block that isn’t too much of a big deal. Lastly, I liked seeing how different groups presented the same information on stellar evolution and seeing how a couple groups displayed the information helped me understand the stage-to-stage process.

Sky Journal #8

Date: November 15, 2010
Time: 1:00 AM
Location: Crestview Lane, Mount Vernon, WA

The picture below is a replica I made of the sky as I saw it last night. The points have been drawn fairly large so that they’re able to be seen.
            a. The constellation Canis Major: Azimuth: 150⁰ Altitude: 50⁰. I was really excited to be able to see this one because this is one of the few constellations that actually looks like what is supposed to look like. I was able to see the head and the front legs of the dog as well as its back but the rest of the constellation was too close to the horizon.
            b. Sirius: Azimuth: 150⁰. Altitude: 80⁰. This star helped me pick out the constellation Canis Major as it is noticeably brighter. It marks the neck of the dog.
            c. Rigel: Azimuth: 170⁰. Altitude: 30⁰. Stellarium tells me that this star is supposed to be the foot of Orion. I was not able to see him but I was able to make out this star because it stood out in brightness above the rest.

             The planet I live on, Earth, is one of eight planets that rotate around a star that we have named the Sun.  The Sun and these eight planets make up our solar system. My solar system is only a small part of my galaxy, the Milky Way, which has been measured to be 1,000 light years in diameter and looks like a spiral with two major arms. To be more specific about my planet’s location in terms of the Milky Way, you can find Earth on Orion which is the minor arm that connects to Perseus, a major arm. My galaxy is one of 67,000 galaxies and is part of a cluster of galaxies known as The Local Group. The Local Group is part of a supercluster known as the Virgo Supercluster. The galaxies in my universe are clumped together in various groups and they all rotate very slowly and it is theorized that because our galaxies rotate, our entire universe rotates as well. In terms of location, the Milky Way galaxy is to the far right of the universe.
            The origin of my universe, as explained by the Big Bang Theory, was essentially protons and neutrons fusing to form hydrogen which then fused to become helium leaving the majority of nuclear matter in my universe to be composed of hydrogen and helium. The beginning of the universe there was just dark matter and over time stars began to form and as more stars were formed and evolved, galaxies formed which got us to where we are now at 13. 7 billion years old. My universe is very exciting because everything is always moving and changing. The galaxies in my universe are moving away from each other (with the exception of one galaxy, Andromeda, which is actually moving toward the Milky Way!). It is fairly universally (no pun intended) understood that the universe will continue to expand forever as the galaxies will continue to move away from each other but it is also theorized that if there is not a lot of dark matter than the universe will have to stop expanding and will begin to shrink until nothing is left.  

Sherwood,, Rena. "Where Is Earth in the Universe?" EHow | How To Do Just About Everything!
| How To Videos & Articles. EHow, Inc., 1999. Web. 29 Nov. 2010. <http://www.ehow.com/about_4674096_earth-universe.html>.

"The Universe Adventure - Composition." The Universe Adventure - Home. UC  Berkeley, 7 Aug. 2007. Web. 29 Nov. 2010.
            <http://universeadventure.org/big_bang/elemen-composition.htm>.

"Future of Universe." Welcome to the History of the Universe. Penny Press Ltd., 2010. Web. 29 Nov. 2010.        
<http://www.historyoftheuniverse.com/futuuniv.html>.

The Drake Equation

Problem: To estimate the number of existing extraterrestrial civilizations in the Milky Way.

Hypothesis: I have a hard time believing there to be life outside of our own planet though I do think it is fairly possible so I expected the number to be at least one.

Procedure: We estimated the values of different variables in the given Drake Equation and solved the equation using our estimated values.

Data and Calculations: Are on the hard copy of the lab that will be turned in on the day of the exam.

Conclusions: Of course what we figured out to be the number of extraterrestrial civilizations is entirely estimated but the value was a great deal less than what I originally thought it would be around. Error lies in our belief in the odds which is why our value compared to the value of another group is going to be very different. I have a hard time agreeing with the probability of our answer as it is ≤1 which does not make sense because including Earth, the value should be ≥1. Reflecting on the actual value of the Drake Equation I also find it hard to believe that there are sixty other intelligent civilizations that are able to communicate. I guess I do not really know what I believe to be the value but I do know that finding out whether or not others exist does not seem like it is worth the money to me.

Hubble's Constant

Problem: To determine the relationship between galaxy distance and velocity.

Hypothesis: Logically thinking I did not figure there to be any relationship between the distance of a galaxy and its velocity.

Procedure: We were provided with a list of data indicating the velocity and distance of certain galaxies. Using this information we plotted this data and drew a line of best fit. We then answered some questions about the relationship we found.

Data and Calculations: Are included on the hard copy of the lab that will be turned in on the day of the test.

Conclusion: We found that the relationship between the distance and velocity of a galaxy is direct which explains to us that objects in are galaxy that are further away are moving faster. This was my aha moment because I did not expect there to be a difference in velocity between galaxies of different distances from us. Some error is found in our graph because we estimated the velocity of each galaxy so each person’s estimate differs by ±2 or 3 km/s.

Galaxy Sort Activity

We grouped the photos into five groups

1)      This group contains seven photos that are spiral galaxies as seen from “above” the galaxy. The last three are a subgroup of spiral galaxies that are bared.

a.      M101

b.      NGC 6946

c.       M81

d.      M51

e.      NGC 1073

f.        NGC 1365

g.      M 109

2)      This group contains single objects that look like just a single bright star.

a.      M87

b.      M59

c.       M32

3)      This group contains unusual looking galaxies that do not fit into a category.

a.      NGC 2146

b.      Arp 252

c.       M82

4)      This group contains galaxies with many stars. These are irregular galaxies that are clusters without organization.

a.      L101

b.      Large Magellanic Cloud

5)      This final group has galaxies that look brighter in the center. We can see the thickness but it could be that these belong in the first category and are just seen from a different angle.

a.      NGC 253

b.      NGC 4650 a

c.       M65

d.      M104

e.      NGC 4565

After the activity we learned that the tree categories that astronomers use are spiraled, bared spiraled and irregular.

Messier / NGC Object

M65, also known as NGC 3623, was cataloged on March 1, 1780 and described by Charles Messier himself as a “very faint nebula without stars”. M65 can be found in Leo, at right ascension 11:18.9 and declination +13:05, and forms the Leo Triplet group alongside M66 and NGC 3628 at a distance of about thirty-five million light years. It looks fairly spiral despite being affected by the gravitational pull of the other two galaxies in the triplet. The arms of the spiral are tightly wound, a central lens is seen quite strongly and a dust lane marks the facing edge from which some knots can be seen. The image below was taken with the Anglo Australian Telescope by David Malin.

http://antwrp.gsfc.nasa.gov/apod/ap960812.html

Below is a picture of the entire Leo Triplet because I thought it was cool.  

http://messier.obspm.fr/Pics/More/m66g_aat.jpg

            Frommert, Hartmut, and Christine Kronberg. "Messier Object 65." SEDS Messier     Database. 30    Aug. 2007. Web. 22 Nov. 2010. http://messier.obspm.fr/m/m065.html.

Nemiroff, Roberto, and Jerry Bonnell. "APOD: August 12, 1996 - Leo Triplet Spiral Galaxy M65." Astronomy Picture of the Day. NASA, 12 July 1996. Web. 22 Nov. 2010. <http://antwrp.gsfc.nasa.gov/apod/ap960812.html>.

Cepheid Variable Lab Write-Up

Problem: Graph the apparent magnitude and the log of the period of a set of stars and use that information to determine a relationship between the two variables and use that information to calculate the apparent magnitude and distance of a star in SMC with the same period.

Hypothesis: I could tell from looking at the table of data that the relationship between apparent magnitude and the log(Period) would be fairly linear. I did not think, however, that using one set of data and the graph drawn from that set could give accurate results for the apparent magnitude and distance of a completely different star.

Procedure: 1) I plotted the table of values. 2) I drew a line of best-fit for the scatter plot. 3) I used that graph and line of best fit to determine the relationship between a Cepheid variable’s period and luminosity or apparent magnitude. 4) I used my line of best-fit to estimate the apparent magnitude of a star located in SMC (which has a period equal to that of delta-ceph). 5) I used the given equation to find the absolute magnitude of delta-cephei. 6) I then used that information and the given equation to find the distance of the star in SMC and expressed that answer in both parsecs and light years.

Data and Calculations: Can be found on the sheet and graph that will be handed in tomorrow.

Conclusion: From this lab I learned that the relationship between a star’s period and apparent magnitude is inverse and fairly linear. I also learned, to my surprise, that the apparent magnitude can be used to find the distance of a star that has the same period. The distance that I eventually determined for SMC was not too far off from the given answer but there was still a fair amount of error in my calculations. The error primarily came from my graph. I plotted my points by hand and the line of best-fit is always a total estimation. This is was a problem in this particular lab because a large part of my calculations were based on a number (the apparent magnitude of SMC) that was estimated using the line of best-fit on my graph so naturally you can see how a less-than-perfect line of best-fit would result in inaccuracy in determining the apparent magnitude. Another possible reason is the imprecision of my numbers as the rules for significant digits allows for a limited amount of precision.

Age of Stars Lab Write-Up

Problem: To find the ages of two clusters of stars by plotting stellar data on a color-magnitude diagram.

Hypothesis: I believe that the age of M45 will be significantly younger than that of 47 Tuc as 47 Tuc is a globular cluster and those tend to contain older stars.

Procedure: 1) I plotted both sets of data in the form of a scatter plot. 2) I identified the red giant stars on the graph and circled them. 3) I determined which of the two clusters is close to Earth. 4) I estimated the lifetimes of each of the clusters using the table provided that indicates lifetime as it relates to spectral type.

Data and Calculations: Can be found on the worksheet and graph that will be turned in tomorrow.

Conclusions: From this lab I learned how color and magnitude can be used to determine the rough age of a star or star cluster. My hypothesis was correct in that the stars in 47 Tuc are in fact older than the stars in M45. Possible error in this lab is found in the inaccuracy of the graph and the age estimate is only rough as we can only guess as to the spectral classification.

Spectral Classification Lab Write-Up

Problem: To understand the Morgan-Keenan system of spectral classification, find behavior of absorption lines and the relationship between wavelength, temperature, Balmer lines and spectral classification.

Hypothesis: Prior to doing the lab I thought that stronger Balmer lines would indicate a higher temperature.

Procedure: 1) I described the spectra in terms of flux pattern. 2) I estimated the Balmer line strength of each panel and ordered them from strongest to weakest lines. 3) I estimated the peak wavelength of each panel. 4) I used the estimated wavelengths to determine that temperature of each panel using Wein’s Law. 5) I used those temperatures to identify the hottest and coolest stars and ordered all panels from hottest to coolest. 6) I compared the order of temperature to the order of Balmer line strength to see if there was any relationship between the two.

Data and Calculations: Can be found on the lab worksheet that will be turned in tomorrow.

Conclusions: The lab helped me determine that there is somewhat of a relationship between Balmer line strength and temperature but the relationship isn’t entirely direct. I found that temperature was greatest in those stars with a Balmer strength that was neither low nor high. I was also reminded that peak wavelength is always a good indication of temperature and was given a greater understanding of how spectral classification can be used when you know the temperature of a given object (in this case, each panel of stars).

Sky Journel #7

Date: November 4, 2010
Time: 11:00 PM
Location: Crestview Lane, Mount Vernon, WA

The picture below is a replica I made of the sky as I saw it last night. The points have been drawn fairly large so that they’re able to be seen.
            a. Capricornus: Azimuth: 70⁰ Altitude: 300⁰ NW. I wasn’t able to see the head of Capricornus but I was able to make out the box-like body.
            b. Jupiter: Azimuth: 80⁰. Altitude: 40⁰ NE. I thought it was interesting to see how much Jupiter moved from when I viewed it last week whether that is due to the change of date or the time I went out.
            c. Fomalhaut: Azimuth: 10⁰. Altitude: 110⁰ SE. This star was fairly noticeable but I was really unsuccessful in trying to find the entire constellation, Piscis.

Sky Journel #6

Date: October 28, 2010
Time: 8:30 PM
Location: Crestview Lane, Mount Vernon, WA

The picture below is a replica I made of the sky as I saw it last night. The points have been drawn fairly large so that they’re able to be seen. With the help of Stellarium I was able to actually see full constellations because I had a better idea of what I was looking for but I’m still not convinced that they look like the shape that they’re supposed to look like.
            a. Piscis. Azimuth: 30⁰. Altitude: 190⁰ SW. This one was fairly hard to see because it was so low on the horizon.
            b. Capricornus: Azimuth: 75⁰. Altitude: 45⁰ NE. The connection of the stars looks a lot more like a bull to me but Stellarium lets you see the image over the constellation which is cool.
            c. Jupiter: Altitude: Azimuth: 90⁰. 230⁰ NW. I think this was Jupiter. It could have been a star but it stood out slightly in color.

Weekly Reflection 11/8-11/12

The most difficult part for me this week was the labs. I had to skip one of them to go to a corporate meeting and I had difficulty understand the math concepts for both. I think that the actual plotting of the data was time consuming and I realize it can be done on excel but I couldn’t figure out how to overlap both sets of data on the same scatter plot. Aside from the labs I found the lectures to be informative and it was awesome to have a holiday this week! As for the test, I think I did okay on it and I’m sooooo glad that we are able to have notes, it takes away a lot of the stress of memorizing and I think it allows us to think about concepts more when we aren’t worried about memorizing formulas and information. I did think that the test included a lot of writing but with a two hour block that isn’t too much of a big deal. Lastly, I liked seeing how different groups presented the same information on stellar evolution and seeing how a couple groups displayed the information helped me understand the stage-to-stage process.

Weekly Reflection 11/1-11/5

I didn’t have any trouble with the lab on Monday and the concepts this week were pretty easy to understand. The mythology on my constellation research was pretty interesting and I liked hearing about the mythology of everyone else’s in my group. At this point I don’t feel prepared for the test next week but there are a few things I can do to change that so I’m not too worried about it. My aha moment this week was learning about black holes as I’ve always heard about them but never really understood what they are and I think the evolution of stars is cool to see in picture form.

Weekly Reflection 10/25-10/29

The test this week went okay. I felt like I pretty much knew what would be on the test. I find Chapter 10 pretty easy to grasp as math is always easier for me to understand rather than concepts. I think it would have made more sense to study stars in this depth at the beginning of the quarter when we began looking at constellations and the celestial sphere. I unfortunately had to miss the lab on Friday but I have done it myself and didn’t have any difficulty with it.

Stellar Evolution APOD: Methuselah Nebula MWP1

        This picture features a planetary nebula at a distance of 4,500 light years away. Planetary nebula is one of the final stages of stellar evolution as the central star is shrugging off its outer layers to advance to a white dwarf and eventually cease of the life of the star. This particular nebula is one of the largest known with a diameter of nearly 15 light years and can be found in the constellation Cygnus the Swan. The average planetary nebulae typically last 10 to 20 thousand years but Methuselah Nebula has an age of 150 thousand years which has given astronomers great insight into the evolution of its central star. This star type is unique as you can physically see the star’s outside layers being shed in the pink and blue colored debris surrounding the central star.

Constellation Project:

         Scorpius is one of the twelve constellations of the zodiac and is most visible in Washington in July and throughout the rest of the summer, can be seen by viewers located at latitudes of 42⁰ and above and is usually seen just above the horizon. Some of the five brightest stars of Scorpius are Antares, Graffias, Dschubba, Sargas and Shaula. The brightest star is Antares which is a red supergiant with an M1 spectral classification, an apparent magnitude of 0.9 and a distance from the earth of 520 light years. Graffias is the actually the sixth brightest star in this constellation though it is given the title of beta because of its position in the constellation and is actually the combination of two stars, Beta-1 and Beta-2. Beta-1 has a magnitude of 2.62 and Beta-2 has a magnitude of 4.92. Both stars in Graffias are 530 light years away which 2200 astronomical units apart, are class B stars and appear bluish-white to the eye.
        The third star in Scorpius is Dschubba which is a spectral type B0.2 IV star, has an apparent magnitude of 2.29 and a distance of 400 light years. The fourth star is Sargas which can be found 270 light years away from Earth and has an apparent magnitude of 1.86 and is a spectral type F1II star. Shaula is the fifth brightest star in Scorpius and is a bluish-white star of spectral class B1 V, has an apparent magnitude of 1.62 and is 300 light years away from Earth. Some other objects contained in Scorpius include open clusters Messier 6 and 7 and globular clusters Messier 4 and 80 and the star U Scorpii which is the fastest nova with a period of around 10 years.

 

Sky Journel #5

October 18
Time: 5:45PM
Location: Eagle Drive, Burlington, WA

            The weather was too bad this week to be able to see anything so I made it a point to watch the sunset instead. There isn’t much to say about it. It was pretty orange and pink in color and was at about 290⁰ West.

Sky Journel #4

Date: October 12, 2010
Time: 1:30 AM
Location: Arbor street, Mount Vernon, WA

The picture below is a  replica I made of the sky as I saw it a couple nights ago (note that East is on the top, West the bottom, etc. because I was not facing North and this way is less confusing for me). The points have been drawn fairly large so that they’re able to be seen.
            One constellation I think I saw was Auriga (labeled a on the “map”). Auriga has a really bright star as one of the points of its circle-like head which I was able to make out but I didn’t see any parts of the tail. The azimuth was about 40⁰ (northeast) and the altitude 15⁰.
            Secondly, I thought I was looking at Cassiopeia (labeled b) but I often get it the larger W-shaped constellation confused with it. The azimuth was 350⁰ (northwest) and the altitude was 40⁰.
            There were other stars out obviously but they were all pretty small and not very identifiable for me.

Sky Journel #3

Date: October 7, 2010
Time: 12:15 AM
Location: Arbor Street, Mount Vernon, WA

The picture below is a  replica I made of the sky as I saw it last night (note that East is on the top, West the bottom, etc. because I was not facing North and this way is less confusing for me). The points have been drawn fairly large so that they’re able to be seen.
            The most predominant constellation I could see was Ursa Major (labeled a) though I was not able to see all points of the constellation due to Washington’s infamous weather. The azimuth of Ursa Major from my location was about 350 ⁰ (north) and the altitude was about 40⁰.
            The only other constellation that I was able to make out was what looked to be pieces of Cetus (labeled b). I was able to see most of the points of the smaller pentagon, the connecting star and the tip of the large pentagon-like shape. The azimuth of Cetus from my location was 180⁰ (south) and the altitude was about 40⁰.
            In addition to constellations, I was able to see a fairly bright star which I though could possibly be the bright point on the constellation Cygnus (labeled c) which had an azimuth of 280⁰ (northwest) and an altitude of 65⁰.
            Lastly, I saw another bright star close to Cygnus but I think it was too bright to be part of Cygnus and I determined it was a bright point of the constellation Lyra. This star had an azimuth of 285⁰ (northwest) and an altitude of 65⁰.

Properties of the Sun Lab Write-Up

Problem: Use images of the Sun to find the rotation period of the Sun, and to find the velocity of matter leaving the Sun through a coronal mass ejection.

Hypothesis: It was my guess that we could determine the velocity of a coronal mass ejection because we had a way to determine distance and had photos that were representational of time but I figured our method would not give us the most accurate measurement as there is a fair amount of room for error.

Procedure #1: The following are the steps used for our first procedure: 1) we determined the diameter in pixels using the image of the sun. 2) We looked up the actual diameter and divided the actual diameter in km by the measured diameter in pixels and determined a km/pixel image scale. 3) We measured the distance in pixels that the coronal mass ejection moved and multiplied that number by our scale factor to determine the distance the mass ejection moved. 4) We used our calculations to determine the period of the sun in days.

Procedure #2: The following are the steps used for our second procedure: 1) we determined a new image scale by measuring the diameter of the sun in pixels and dividing the actual diameter of the sun in km by the pixel diameter. 2) We pinpointed both of the minimum heights in pixels of the mass ejections, used the distance formula to determine the pixel distance moved and then converted that number to km using our scale factor. 3) We pinpointed both of the maximum heights in pixels of the mass ejections, used the distance formula to determine the pixel distance moved and then converted that number to km using our scale factor. 4) We used our calculated distances to determine the change in height in km. 5) We used the times recorded below each picture to determine the time change. 6) We divided our calculated distance covered by the time it took for the mass ejection to move that distance and found the velocity of the material in km/h. 7) We converted our velocity to mi/hr.

Data & Calculations: Can be seen on the hardcopy of the lab which will be turned in on the day of the test.

Conclusion: We were able to determine the velocity of the coronal mass ejection using simple pictures, pixel measurements and formulas which was interesting.  We determined that the material left the sun at an extremely fast velocity when compared to the velocity of things we are familiar with like cars and airplanes which is kind of mindboggling to think about. As with all labs there was some error in our calculations. This error came from unsteady hands used to determine pixel location as well as small photos that do not allow for very precise measurements.

Weekly Reflection: 10/18-10/22

Most of my time spent this week was spent filling in missing holes on all my labs, filling out the write-ups and working through the different assignments, projects and worksheets. I found my solar research and listening to the solar research of others to be interesting and informative because I have never really thought about what the sun looks like or is composed of which is why I also found the lectures to be interesting. My aha moment was realizing how much there actually is going on in the sun and on the surface of the sun. Another aha moment was when I did my solar research and learned how coronal holes on our sun that is so far away can actually affect our communication. Finally, I enjoyed the different APODs because I think pictures of the solar system are always really pretty as they are so colorful and something that is fairly unfamiliar to me.

Identifying Lines in the Solar Spectrum Lab Write-Up

Problem: The purpose of the lab was to identify lines of the solar system using Fraunhofer lines.

Hypothesis: As this lab was primarily data collection there was not much to hypothesize.

Procedure: We used a picture we were provided with to pinpoint the pixel location of two separate lines and found the pixel distance between the two. From there we used the table we were provided with to find the distance in nanometers and used nm/pixels to establish a scale factor. Our next step was to identify unknown lines along the same spectrum. We first chose one line to serve as our reference point and determined the pixel location and the given wavelength in nanometers. We then found the pixel location of each line and determined the distance between that line and the reference point. Next, we multiplied the pixel distance by our previously calculated scale factor to get the wavelength in nanometers of each element. From this point we were able to use the wavelength to determine the element name of each unknown line.

Data: Can be seen on the hardcopy of the lab that will be turned in on the day of the test.

Calculations: Can be seen on the hardcopy of the lab that will be turned in on the day of the test.

Conclusions: We were able to determine some of the different elements in the solar spectrum however our calculations could not be entirely accurate. Because we were using unsteady hands and trying to pinpoint small lines there is some error in our pixel determination which is the foundation on which all other questions and calculations are based. We saw this error come into play when we used the calculated wavelength to determine the name of the element but it was obvious that our calculations were off a bit because none of the elements had the exact wavelength that we calculated so we had to round our numbers to the element with the closest wavelength. Error aside, it was interesting to see how we could use something as simple as a picture on a computer screen to determine different elements and wavelengths.

Solar Research: Question #6

In 1973 the United States launched its first space station, Skylab. Skylab was in the Earth’s orbit for about six years (from 1973-1979) and was equipped with x-ray telescopes to reveal the structure of the sun, specifically the corona of the sun. These x-ray images taken from both the Skylab and other satellites revealed the sun to have darker, colder spots on its corona that can be as large as the earth’s diameter and have plasma with lower density than average. We have since learned that coronal holes occur when the magnetic field of the sun is open to interplanetary space and there are regions on the sun where solar magnetic fields loop back to the sun forming arches which are depicted on x-rays as brighter areas than the rest of the corona.
            We should care about coronal holes because open configuration of the magnetic field allow particles to escape into space and research has found that coronal holes are the source of high speed solar wind streams which, when coming in contact with the Earth, can cause geomagnetic storms. Periods of high amounts of solar activity eject mass from the coronal holes and periods of low solar activity geomagnetic storms are created. From our perspective, it is important to monitor solar activity in and from coronal holes because these holes can last for several months and following them gives us the ability to predict geomagnetic disturbances

Image: http://sprg.ssl.berkeley.edu/~hhudson/drafts/sw10/sch.pdf

Darling, David. "Coronal Hole." The Worlds of David Darling. 1999. Web. 21 Oct. 2010. <http://www.daviddarling.info/encyclopedia/C/coronal_hole.html>.

Solar System APOD: Saturn's Moon Helene from Cassini

http://apod.nasa.gov/apod/ap100310.html

          My APOD of the solar system (credit to NASA/JPL/SSI) features Saturn’s moon Helene, a smaller moon that is the sixth farthest from Saturn.  Helene was discovered using ground-based observations in 1980 and was named after Helen of Troy in 1988 who was the granddaughter of Cronus (Saturn) in Greek mythology.  One theory is that Helene was formed from material in the rings being clumped together. This conflicts with the Solar Nebular Theory because scientists found that Helene is actually less dense than an asteroid and is not composed of dust and gas as the theory suggests. I really just chose this picture because Helene is in the solar system and because I think the light and shadowing of the picture is cool. I also think it’s cool that they were able to get so close to the moon (within two Earth diameters) and get us this good close-up picture.

Bergman, Jennifer. "Helene." Windows to the Universe. National Earth Science Teachers Association, 19 Jan. 2001. Web. 21 Oct. 2010. http://www.windows2universe.org/saturn/moons/helene.html

Edwards, Lin. "Formation of Saturn's Ring Moons Explained." PhysOrg.com - Science News, Technology, Physics, Nanotechnology, Space Science, Earth Science, Medicine. PhysOrg.com, 10 June 2010. Web. 21 Oct. 2010. <http://www.physorg.com/news195368117.html>.

Meteorite Lab

Problem: Can we calculate the size of Canyon Diablo Meteorite by using simulation?

Hypothesis: I figured that the size of the Canyon Diablo Meteorite could be roughly calculated but the error percentage would be really high because we cannot take into consideration the speed it hit the earth at or how far the meteorite was falling from.

Procedure: We filled a box with flour and some cocoa (for color differentiation) and dropped a marble from one meter five times each and then we dropped another marble from the same high five times. With each drop we measured the size of the diameter of the crater from the very outer edge to the opposite outer edge. From this point we used the ratio given to us on the lab to cross multiply and get an estimate on what the diameter of the Canyon Diablo Meteorite might have been.

Data: Can be seen on the hardcopy of the lab which will be turned in on the day of the test.

Calculations: Can be seen on the hardcopy of the lab which will be turned in on the day of the test.

Conclusions: We concluded that simulation can give us an idea of the size of Canyon Diablo Meteorite but the calculations of my group were not very accurate. I think one possible reason for this is the precision of the calculations. If we had measured the diameter of the crater made to the tens of thousandths place we would have more accuracy.

Spectra Lab

Problem: The purpose of this lab was to use spectrometers to look at various heated elements as well as the sun and fluorescent lights and observe the emission, absorption and continuous spectrum of the elements.

Hypothesis: I expected that none of the elements would give off a continuous spectrum though I thought the sun would and I did not know what to expect of the fluorescent lights though I figured it would be similar to that of the elements.

Procedure: We used spectrometers to look at the elements, the sun and the fluorescent lights and recorded the lines that were given off or absorbed by each element.

Data: See the hardcopy of the lab that will be turned in on the day of the test.

Calculations: See the hardcopy of the lab that will be turned in on the day of the test.

Conclusion: I learned that all the heated elements we observed gave off emission lines, the sun gives off a continuous spectrum and fluorescent lights give off an absorption spectrum. I thought it was really interesting to actually see the colors that the different elements give off and it really gave me a feel for how simple it is to use spectrums to identify elements.

Satellite Motion Lab Part 2

	Period (s)
Mass (kg)	1	2	3	Average
0.50	0.33	0.33	0.33	0.33
0.30	0.36	0.35	0.39	0.37
0.20	0.43	0.44	0.47	0.45
0.10	0.66	0.66	0.67	0.67
0.05	0.82	0.96	1.00	0.93

As I cannot get my scatter plots to paste here I will turn them in on the test day with the rest of my homework.

Calculations: We were instructed to use our data to calculate the mass of the rubber stopper (the “satellite” in this experiment) and find the percent error as compared to the measured mass of the stopper. Because we used five different radii in our data collection I am going to do five separate calculations of the mass of the stopper and our percent error.

1.      Velocity=distance/time

 =2´p´0.20 ² / 0.28 = 4.5 m/s ²

                         Centripetal acceleration=velocity² / radius

                                                    =4.5 ² / 0.20 = 101

            Centripetal force=mass ´ centripetal acceleration

            (0.20 kg ´ 9.8 m/s)=mass ´101

                                  1.96=mass´101

                                 Mass=1.96/101

                                 Mass=0.019 kg

            % Error=(calculated-actual)/calculated

                        =(0.019-0.026)/0.019

                        = -0.37

                        =37% error

2.      Velocity=distance/time

 =2´p´0.30 ² / 0.34 = 5.5 m/s ²

                         Centripetal acceleration=velocity² / radius

                                                    =5.5 ² / 0.30 = 100.8

            Centripetal force=mass ´ centripetal acceleration

            (0.20 kg ´ 9.8 m/s)=mass ´100.8

                                  1.96=mass´101

                                 Mass=1.96/101

                                 Mass=0.019 kg

            % Error=(calculated-actual)/calculated

                        =(0.019-0.026)/0.019

                        = -0.37

                        =37% error

3.      Velocity=distance/time

 =2´p´0.40 ² / 0.43 = 5.8 m/s ²

                         Centripetal acceleration=velocity² / radius

                                                    =5.8 ² / 0.40 = 84.1

            Centripetal force=mass ´ centripetal acceleration

            (0.30 kg ´ 9.8 m/s)=mass ´84.1

                                  1.96=mass´84.1

                                 Mass=1.96/84.1

                                 Mass=0.023 kg

            % Error=(calculated-actual)/calculated

                        =(0.023-0.026)/0.023

                        = -0.13

                        =13% error

4.      Velocity=distance/time

 =2´p´0.5 ² / 0.46 = 3.4 m/s ²

                         Centripetal acceleration=velocity² / radius

                                                    =3.4 ² / 0.50 = 46.2

            Centripetal force=mass ´ centripetal acceleration

            (0.30 kg ´ 9.8 m/s)=mass ´46.2

                                  1.96=mass´46.2

                                 Mass=1.96/46.2

                                 Mass=0.042 kg

            % Error=(calculated-actual)/calculated

                        =(0.042-0.026)/0.042

                        = 0.38

                        =38% error

5.      Velocity=distance/time

 =2´p´0.60 ² / 0.49 = 4.6 m/s ²

                         Centripetal acceleration=velocity² / radius

                                                    =4.6 ² / 0.50 = 42.3

            Centripetal force=mass ´ centripetal acceleration

            (0.20 kg ´ 9.8 m/s)=mass ´42.3

                                  1.96=mass´42.3

                                 Mass=1.96/42.3

                                 Mass=0.046 kg

            % Error=(calculated-actual)/calculated

                        =(0.046-0.026)/0.046

                        = 0.43

                        =43% error

Conclusion: The conclusion from this lab is that the radius of a satellite’s orbit is directly related to its period and that the centripetal force is inversely related to the period of a satellite’s orbit. My aha moment was when I plotted the date we collected and saw more clearly the relationship between the two variables. I learned that the escape velocity of a satellite with a circular orbit is ≥8km/s and <11.2 m/s and that the escape velocity of a satellite with an ellipse orbit is ≥11.2 m/s. Finally, I learned that centripetal force is the force directed toward the center of a body’s orbit and centrifugal force dragging a body away from the center of rotation and is equal and opposite to the centripetal force.