CHICOS FAQ
(Frequently Asked Questions)
A Reference for CHICOS Schools
1. What does C.H.I.C.O.S stand for?
2. What is the use of CHICOS?
3. What are the benefits of CHICOS?
4. When was the CHICOS project started?
5. Who came up with the idea for CHICOS?
6. How old do you have to be to work with CHICOS?
7. When you first started the CHICOS program did you think it would be a cpmplete success?
8. Why did you start CHICOS at high schools?
9. What degree do you need to do what the CHICOS people do?
10. What was the first school you put a computer in?
11. Is C.H.I.C.O.S. a company?
12. Who chose our school to help with this project? Why?
13. How did you discover this job of detecting cosmicrays?
14. How important and recognized in the CHICO’s work? Isit internationally known?
15. How much money does it take this program to keep running?
1. What does C.H.I.C.O.S stand for?
California High school Cosmic ray Observatory
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2. What is the use of CHICOS?
CHICOS is a large science experiment that looks for high energy microscopic particles that are emitted by distant stars. By studying these particles we can learn more about our universe. The knowledge we gain might have technological aplications someday, but it is hard to know until we understand more about the basic science involved. (This is how most new technology starts, by the way.)
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3. What are the benefits of CHICOS?
CHICOS has many benefits. For one thing it is helping us learn more about the universe. It is unique because, unlike most large science experiments, high school, middle school and even elementary school teachers and students get to be a part of it and learn science at the same time.
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4. When was the C.H.I.C.O.S project started?
CHICOS started as an idea in 2000. It took some time to develop the detector design and gather a startup group of teachers. The first detectors were installed in schools during the fall of 2001.
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5. Who came up with the idea for CHICOS?
Bob McKeown, a professor of physics at Caltech, came up with the idea for CHICOS. Professor McKeown's other research projects include neutrino observations and other experiments in nuclear physics and particle astrophysics.
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6. How old do you have to be to work with CHICOS?
You can be almost any age. We now have CHICOS detectors located at elementary and middle schools as well as high schools.
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7. When you first started the CHICOS program did you think it would be a complete success?
As with all large scientific enterprises, you never know for sure if it is going to be successful. All you can do is work very hard and try to think of all of the things that could possibly go wrong ahead of time.
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8. Why did you start CHICOS at high schools?
High schools are a great place to put our detectors for several reasons. First of all, the high schools in the Los Angeles area are evenly distributed over a wide area and so make a good detector array. Another reason is because most schools nowadays have high-speed internet connections so that the detectors can communicate with the central server at Caltech. A really big advantage of using schools is that there are teachers and students there who can help maintain the detectors and contribute to the experiment in lots of other ways.
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9. What degree do you need to do what the CHICOS people do?
The people who work on CHICOS have a variety of educational backgrounds. We have both college professors who have PhD’s and college students who don’t have Bachelors degrees yet working at Caltech and at other universities and colleges. There are also all of the teachers and their students at the schools where the CHICOS detectors are located.
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10. What was the first school you put a computer in?
The first school detector sites were Sylmar High School and Monroe High School, installed on the same day (Sept. 10, 2001). Harvard-Westlake School, Louisville High School, and Sherman Oaks CES got detectors ten days later.
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11. Is C.H.I.C.O.S. a company?
No, CHICOS is not a company. CHICOS is an experimental collaboration, funded by public and private money and run from within the physics department at Caltech. It is an academic research and outreach project; we are trying to learn more about the universe, and to involve Los Angeles area schools in that learning process.
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12. Who chose our school to help with this project? Why?
Your school was probably chosen because of its location, but also because a teacher at you school was interested in becoming a part of the CHICOS experiment.
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13. How did you discover this job [subject, problem] of detecting cosmic rays?
Professor McKeown became interested in detecting cosmic rays because he attended talks and read journal articles in which people talked about the puzzle of ultra-high energy cosmic rays. Other members of the CHICOS collaboration, particularly at UC Irvine, have been involved in related areas of cosmic ray research for many years. Scientists generally learn about each other's ongoing research efforts and interesting new problems by attending conferences, reading scientific journals, and hearing from each other through talks, visits, e-mail, and other formal or informal contact. When we hear of an interesting topic and we think we have a reasonable, fun, or original way of contributing to that field -- well, then a new research project is born.
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14. How important and recognized is the CHICOS work? Isit internationally known?
CHICOS is one of the smallest research projects to measure ultra-high energy cosmic rays. However, there are very few research projects that have measured ultra-high energy cosmic rays -- just a handful around the world. There are also several other school-based cosmic ray projects in North America and around the world. CHICOS is known internationally for its unique blending of research and education. CHICOS project members have attended national and international conferences and given talks about CHICOS scientific research and educational programs.
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15. How much money does it take this program to keep running?
More than we have!
In all seriousness, CHICOS is very frugal on the scale of cosmic ray observatories and other related research projects. However, the goal of involving our school participants in genuinely new cosmic ray research cannot be accomplished for free. The installation of each new CHICOS site costs roughly $5,000 in detection equipment and labor. Schools are not asked to pay these costs, but to take care of whatever facilities preparations are necessary to accomodate the installation in their building. Master's and PhD-level scientists are involved in the operation of the existing array and the analysis of CHICOS data, as well as in working with schools through workshops, summer programs, and classroom visits. These activities are supported through the grants we seek from private foundations and government agencies.
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1. What is stardust? What are cosmic rays?
2. How tiny are cosmic rays?
3. How light are cosmic rays?
4. Can you see cosmic rays through a telescope?
5. Is it possible to see cosmic rays? What do cosmic rays look like?
6. How often do cosmic rays fall? How many cosmic rays land on earth in one hour?
7. Where do cosmic rays come from?
8. How fast do cosmic rays travel?
9. How do cosmic rays go through you?
10. If cosmic rays come from stars, how do they travel such long distances?
11. If we breathe (cosmic ray) stardust, will it interfere with our health?
12. Why do cosmic rays exist?
13. Can we tell if cosmic rays have fallen on us?
14. Do the cosmic rays capture stardust?
15. Will Cosmic Rays collapse the Sun?
16. Do Cosmic Rays carry any electrons or protons?
17. Can Cosmic Rays kill people?
18. How many cosmic rays are there in the universe?
19. Can a cosmic ray become more powerful while heading to
earth?
20. What field of science is cosmic rays in?
21. How can cosmic rays help us? What are the uses of cosmic rays?
22. Who gave it the name "cosmic rays?"
23. Will cosmic rays cause mutation?
24. Do you think there will be improvements to detect
cosmic rays?
25. How long do cosmic showers usually last?
26. What are the odds of ultra high energy ray disturbing
your particles in your head?
27. Are there areas where these rays occur more
frequently?
28. Are there any devices that can transfer cosmic rays to
energy?
29. What are black holes?
1. What is stardust? What are cosmic rays?
"Stardust" is a word that people have been using in stories, poems, and songs for a lot longer than the modern study of stars. We have to remember that the wonder and excitement of the stories is what came first, getting people interested in knowing what the stars were actually made of.
The "stardust" we collect is a dusting of microscopic particles that come streaming off the surface of a star. Scientists usually refer to these as cosmic rays.
You might have heard of a NASA/JPL mission called Stardust, which is looking at a different kind of dust. They are trying to get a closeup look at the dust and ice tail of a comet, which can shine a bit like a star when the comet comes close to the Sun and the tail lights up in the Sun's rays.
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2. How tiny are cosmic rays?
The cosmic ray particles we are looking for are microscopic. The actual size of one of them would be about 1 billion times smaller than the width of one of your hairs.
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3. How light are cosmic rays?
The cosmic ray particles are individually very light. That's part of why you don't notice when one goes through you! How light are they? Each one is about 1,000,000,000,000,000,000,000 times lighter than a paperclip! But it is lots and lots of tiny particles like these that make up the paperclip, or your body, or the electricity flowing to your house.
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4. Can you see cosmic rays through a telescope?
Not this kind. A telescope lets you get a better view of things that are far away. A microscope is what you would have to use to view things that are small. BUT the cosmic ray stardust is too tiny for ordinary microscopes as well. That's why we detect the particles instead of actually seeing them.
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5. Is it possible to see cosmic rays? What do cosmic rays look like?
Well, we can't see the particles themselves because they are too tiny. Scientists think the particles are protons (basically round) or clumps of protons and neutrons stuck together (called atomic nuclei).
We can see the blue glow in special scintillator plastic when the cosmic rays have hit. Actually near the north and south poles of the Earth, cosmic rays make colored flashes just passing through the atmosphere and the Earth's magnetic field. That's what causes the aurora borealis (or australis), the Northern (or Southern) Lights.
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6. How often do cosmic rays fall? How many cosmic rays land on earth in one hour?
Wow, about two hundred particles per second on each square meter of the Earth's surface. Now, there are 60 seconds in a minute and 60 minutes in an hour, so that would be 200x60x60=720,000 particles per hour on each square meter of the surface. Earth's surface area is about 500 trillion square meters. That means 500 trillion x 720,000 = 360,000,000,000,000,000,000 stardust particles land on Earth in one hour! Still, if you read the answer to how light they are, then you can figure out (with careful counting of all those zeroes) that these 360,000,000,000,000,000,000 stardust particles put together would still only weight about as much as a third of one paperclip.
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7. Where do cosmic rays come from?
Cosmic rays are not rays like sunbeams but streams of very small bits of material that come from the centers of atoms.
A single atom can be roughly imagined like the solar system. An atom has a small center called a nucleus with parts called electrons going around the nucleus a bit like planets going around the Sun. When we talk about a mixture of atoms the atoms' centers are referred to in the plural and are called nuclei. The stars in the sky and all the things that we can see in space are made up of the same kinds of nuclei that we find in atoms here on Earth.
The main difference between these nuclei from the stars (or stardust, as it is sometimes called) and nuclei that we find here on Earth is that the nuclei that come from stars are moving very, very fast. Otherwise they wouldn't have escaped from the stars' gravity in the first place. When these fast-moving cosmic rays hit the detector they can cause the material inside to glow like a firefly. They move so fast because when big stars explode they spray these nuclei all over the place and some of those nuclei reach us on Earth as cosmic rays. Small stars can also produce cosmic rays when their nuclei are sprayed out in the form of a wind called a stellar wind. Other nuclei near a neutron star, massive black hole, or other astronomical object can feel object's strong the magnetic field and bounce off that magnetic field like a pinball, getting faster every time they make a bounce. That is why they end up moving so fast.
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8. How fast do the cosmic rays travel?
The nuclei that make up cosmic rays travel just about as fast as something can travel in nature. This is called the speed of light. This is about 186,000 miles or 300,000 kilometers in a single second. That is like traveling around the Earth seven times in about the time it takes you to blink!
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9. How do cosmic rays go through you?
To understand this you have to remember that you are made of the same things that the cosmic rays are -- atoms, or more accurately pieces of atoms called nuclei. A single atom can be roughly imagined as like the solar system. An atom has a small center called a nucleus with parts called electrons going around the nucleus a bit like planets going around the Sun. And just like there is a large space between the Sun and the planets there is a large space between the nucleus and its orbiting electrons. So when cosmic rays, which are mostly the nuclei of atoms from a star, fly into you they are usually passing right between the spaces of the nucleus and electrons that make up your body. So they do not usually hit anything and can go right though you.
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10. If the cosmic rays come from stars, how do they travel such long distances?
First, how far do these cosmic rays really travel? The stars themselves are very, very far away so cosmic rays must be travelling a long ways just because of that. But, they also float between the stars just like a bottle in the ocean, and can sort of surf magnetic waves between stars. If they surf enough of these waves they can pick up a lot of speed. But this may take a long time and during that time they can travel a distance even greater then the between the stars.
Now, how do the cosmic rays travel so far through space without stopping? There must not be much out there to slow them down. Here on Earth, we are very familiar with situations where friction slows the motion of just about every moving thing we can think of. However, friction is only present when there are different objects to rub or tug against each other. If a cosmic ray traveling through space doesn't rub or tug against anything else, it can travel huge distances without being slowed down much.
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11. If we breathe cosmic rays, will they interfere with our health?
The short answer is no. The amount of cosmic rays is very, very, very small in comparison the with the amount of atoms in the air we inhale every day. Further, the cosmic rays are mostly made up of non-toxic nuclei so again the interference to our health is very small. The great speeds that the cosmic rays travel at can potentially interfere with our health just a little as they break apart molecules in our bodies but this does not happen by breathing it. However, the danger from this is very, very small in comparison to other stressful things like not doing one's homework!
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12. Why do cosmic rays exist?
This is a very good and deep question. One simple answer is that stars through the normal course of their life blow off nuclei through winds or by exploding. Since these nuclei are sprayed off at random in all directions some of them will, of course, fall on the Earth were we see them as stardust so the stardust has to exist. An alternative question would be to ask why do the nuclei and the stars exist? Now we are contemplating the subject of cosmology, a branch of astronomy that tries to understand the processes at work throughout the history of the universe as we know it. Cosmology hopes to explain how the universe developed from its starting point, called the Big Bang, to what we see and know today. However, depending on the meaning of "why" in your question, "why" (as opposed to "how") may be a question that's beyond the realm of science.
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13. Can we tell if cosmic rays have fallen on us?
We cannot tell if they have fallen on us because they are so small and most of the particles go right through our bodies with out us feeling a thing. That is why we need a detector to know about them.
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14. Do the cosmic rays capture stardust?
No, the cosmic rays are stardust. (See Question 1 in this category.)
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15. Will Cosmic Rays collapse the Sun?
No, they won't! The Sun will eventually collapse (in several billion years), but that won't be caused by cosmic rays. The Sun's light and heat come from a nuclear fusion reaction going on in its core. Eventually the Sun will use up all its fuel for this nuclear reactor, and without the power source at its center the Sun will ultimately collapse under its own weight. But we have more pressing worries here on Earth!
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16. Do Cosmic Rays carry any electrons or protons?
Each cosmic ray is an individual subatomic particle (piece of an atom). Some cosmic rays are electrons and protons.
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17. Can Cosmic Rays kill people?
The cosmic rays that reach us here on Earth are not harmful to our health. They have always been around throughout the history of life on Earth. However, the reason they are harmless is that we have the atmosphere above us, shielding us by taking high-energy cosmic rays and dissipating their energy in cosmic ray "showers" like the ones we study. Getting hit by many low-energy cosmic rays is harmless, while getting hit by one high-energy cosmic ray might not be. Thus, cosmic ray exposure is an important concern for space programs considering sending astronauts into space for many months or years at a time.
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18. How many cosmic rays are there in the universe?
Lots and lots! We'll get back to you if we have an estimate on this number!!
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19. Can a cosmic ray become more powerful while heading to
earth?
We're not sure exactly what you mean by "more powerful," but let's assume you mean "more energetic." In that case, it is thought that most cosmic rays do not gain much (if any) energy after they leave the vicinity of their original source. Cosmic rays gain energy primarily by traveling through regions where there is a strong magnetic field gradient, and "bouncing" repeatedly off the magnetic fields. When traveling through interstellar or intergalactic space, a cosmic ray's chance of meeting up with such a region by chance -- and bouncing off it instead of getting slowed or stopped by it -- is very low.
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21. What field of science are cosmic rays in?
The study of cosmic rays involves primarily nuclear science and astronomy. In that way, it is generally considered a field of physics; in recent years, it lives within a subfield called "particle astrophysics." However, cosmic rays, their effects, and their uses also show up in other fields as varied as archaeology and medicine!
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22. How can cosmic rays help us? What are the uses of cosmic rays?
Cosmic rays that arrive here on Earth are important to understand because they may teach us quite a bit about their sources in outer space. Depending on what we learn, these discoveries may lead to technological applications someday.
However, cosmic rays here and now on Earth are used for a few useful or interesting purposes. For example, the carbon-14 whose concentration is measured to carbon-14 date ancient artifacts? The carbon-14 wouldn't be there if it weren't for cosmic rays. Another example: archaeologists from the 1960's through modern times have used cosmic ray fluxes through certain large structures to "cosmic ray image" the insides of those structures to look for hidden rooms and hollow passages -- much like X-raying a person to see the positions of their bones.
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23. Who gave it the name "cosmic rays?"
The popular press wanted to call these particles "Millikan rays," after Robert Andrews Millikan, a prominent physicist who studied them soon after their first discovery in the early 20th century. However, Millikan originally thought the rays from space did not exist, and had to change his mind once he and others collected convincing evidence of their existence. Millikan would have been embarrassed to have had the rays named after him, so he supported the alternate term "cosmic rays."
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24. Will cosmic rays cause mutation?
Cosmic rays can cause mutation. Their likelihood of doing so depends on how much energy per particle they have. The constant background "rain" of low-energy cosmic rays on Earth's surface is thought to contribute significantly to the normal rate of mutation for life on Earth. Exposure to higher-energy cosmic rays, for example, through spending time at very high altitudes or in space, can cause higher rates of mutation and potentially lead to health complications such as cancers.
A related question, especially for those who saw The Fantastic Four, may be: can cosmic rays cause mutations that give us superpowers? To answer this question, we pose a question to you... If you opened up your cell phone and tugged and bent several wires, would your reception improve and could you also suddenly listen to the radio on your phone? Probably not, right? Mutations are random changes in genetic material -- kind of like randomly tugging on some of the wires. Most mutations do absolutely nothing noticeable. A few mess up the organism, causing illness of some kind. And a very, very few might cause the organism to improve in some way. The chance that a mutation will cause Xray vision, superhuman strength, or another cartoon superpower...well, that chance is so small that many people would just refer to it is impossible.
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25. Do you think there will be improvements to detect
cosmic rays?
Almost certainly. There will be improvements in the reliability of cosmic ray detectors, and in our ability to calibrate them. That means our ability to understand the data we take -- determining exactly how much energy a cosmic ray had, for instance, instead of being able to roughly estimate it. However, it's not clear if or when there will be any revolutionary change in the basic methods used for cosmic ray detection.
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26. How long do cosmic showers usually last?
We use the term "cosmic ray shower" to refer to the cascade of subatomic particles falling out of the air because of one "primary" high-energy cosmic ray hitting the Earth's atmosphere. Because these cosmic rays are travelling at nearly the speed of light, an entire shower is over very quickly. A shower typically lasts no more than a few microseconds, or a few millionths of a second. That's why we need automated data acquisition and very precise timing in order to record a shower properly.
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27. What are the odds of ultra high energy ray disturbing
your particles in your head?
Very, very small! See Question 9 in this category for more information.
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28. Are there areas where these rays occur more
frequently?
Cosmic rays in general are more concentrated near the Earth's magnetic poles and less concentrated near the magnetic equator. This is because most cosmic rays are electrically charged particles, and they are funnelled towards the poles by interactions with Earth's magnetic field. Cosmic rays also fall more densely at higher altitudes, since higher altitudes have less atmospheric shielding between them and space.
However, really high energy cosmic rays (like the ones CHICOS is designed to study) aren't much deflected by the Earth's magnetic field, and the showers they cause are strong enough to be seen all the way down to sea level. If there are areas where these high-energy showers occur more frequently, we don't know it yet and we would love to find out!
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29. Are there any devices that can transfer cosmic rays to
energy?
We think you are asking if there are any devices to use cosmic rays to drive humanly or technologically useful "energy sources," in the way that solar cells can convert the Sun's light energy into stored chemical energy useful for electricity needs. If this is the question, then... so far, no uses of this kind are in place. Our detectors do work by letting the cosmic rays deposit energy in scintillator plastic, having that energy convert to light, and then turning that light into an electrical signal using a photomultiplier tube. But the photomultiplier tube needs to be given power to work, and so in total we use electricity rather than getting some.
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30. What are black holes?
The denser and more massive an object is, the stronger its surface gravity. A black hole is an object so dense and massive that nothing, not even light, can escape from its surface. In that case we call the surface an "event horizon," because from the outside we can't see or record any events that might or might not be taking place inside. Black holes are the end result of the supernova explosions of the most massive stars. In addition, even huger black holes reside at the centers of many galaxies, including our own.
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1. How come the detectors can't turn off?
2. Do the people in Caltech make the computers?
3. Why are there faces on the detectors?
4. Why are the detectors white?
5. Why are the detectors shaped like hats?
6. Why are the detectors on top of our classroom?
7. Why do the detectors have a heart beat?
8. How does a detector work? How do the sensors on the roofs know when the cosmic rays hit them?
9. Is there any other way to detect cosmic rays?
10. If lightning hits it will it break?
11. Are the detectors heavy?
12. How fast does the information travel from detector to computer?
13. Do you know how many cosmic rays the detectors detect right that second?
14. How much of the purple stuff (plastic scintillator) is in the detectors on the roof?
15. How many cosmic rays can hit the pods at once?
16. Which time of day do the most cosmic rays hit the pod?
17. What will happen if there's no sun out or if it's raining, hailing or snowing?
18. What is a shmoo in the CHICOS program?
19. What is the CHICOS programming for?
20. Why does the glowing purple thingy glow purple instead of red or green?
21. What would happen if you turn a computer off?
22. Why are there two detectors instead of one or three?
23. How did you make the detectors?
24. Is it hard to make a computer?
25. Why does the memory disappear if the computer is turned off?
1. How come the detectors can't turn off?
The detector can be turned off -- we control it from inside the small orange and black box that goes with your computer. But we try to run it 24 hours, 7 days a week because the big particle showers we are looking for are very rare and we have no way of knowing when they will come.
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2. Do the people in Caltech make the computers?
The computers are just ordinary PC computers that we buy from the same places your family or your school does. We (or students who come to work with us) do make the detectors and the control box (orange and black box with the computer).
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3. Why are there faces on the detectors?
The detectors were built by high school and middle school students working with us. They have to paint the serial numbers, and they like to personalize each set of shmoos for fun. It doesn't hurt anything.
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4. Why are the detectors white?
They're white so they will reflect sunlight and stay as cool as possible up on a hot rooftop all summer. In fact, we got the containers from a previous experiment out in the New Mexico desert where it gets even hotter.
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5. Why are the detectors shaped like hats?
Remember the blue-purple light shining from the piece of scintillator plastic that I showed [in classroom presentations]? Inside the detector at the bottom is a big piece of scintillator plastic giving off light like that. The cone shape is so the light will bounce off the walls and eventually end up hitting the photodetector at the top.
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6. Why are the detectors on top of our classroom?
We wanted detectors at your school so that we could measure when cosmic rays hit your area relative to when they hit nearby schools. Your specific classroom got involved because your teacher is a good sport!
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7. Why do the detectors have a heart beat?
The heartbeat is actually just for the computer. It's a silly thing, but the idea is just to have something that tells us the computer is still on and not frozen or crashed.
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8. How does a detector work? How do the sensors on the roofs know when the cosmic rays hit them?
A cosmic ray hits the scintillating plastic and makes a flash of blue-purple light. A photodetector collects that light and sends a signal to the computer. Then the computer can record exactly when it got hit by checking the time with a special GPS antenna on the roof (official national satellite timing and mapping system).
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9. Is there any other way to detect cosmic rays?
There are several ways to detect cosmic rays (besides the "solid scintillator" detection method used in CHICOS). To learn the basics of several different detection methods, visit a web page provided by the cosmic ray group at the University of Leeds.
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10. If lightning hits it will it break?
If lightning hits near our cosmic ray detectors, they might record some bursts of electrical activity that are related to the lightning and not to cosmic rays. The detector covers are made of fiberglass, so lightning is not very likely to strike them since they don't provide a very good conductive path from sky to ground.
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11. Are the detectors heavy?
The detectors weigh about 150-200 lbs. each. They are very bottom-heavy, and the weight is spread pretty evenly across the bottom surface. Another good reason to leave the detectors alone is that there is high voltage (around 2,000 Volts) inside each detector.
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12. How fast does the information travel from detector to computer?
Good question! Information travels as electrical signals move along the cables (wires) from the detector to the computer. These electrical signals move really fast -- at a speed close to the speed of light but not quite that fast. The exact speed depends on the type of electrical cable we use. For the signal cables we use, which are called RG-58 cables, it takes 77 billionths of a second for signals to travel every 50 feet. Our cables are either 50 or 100 feet long, depending on the distance from classroom to detectors. So... the information gets from the detectors to the computers pretty fast, but slowly enough so that we have to account for that time delay when we record the times of cosmic ray arrivals.
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13. Do you know how many cosmic rays the detectors detect right that second?
By looking at the CHICOS data screen at your school, you can see how many cosmic rays your detectors have measured in the last second (and at any time during the last week). We don't get the data at Caltech that quickly, though. Each CHICOS computer sends us its previous day's data in the middle of the night, so if your detectors do something strange today, we won't know about it until tomorrow morning.
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14. How much of the purple stuff [plastic scintillator] is in the detectors on the roof?
Each detector has about 1 meter x 1 meter x 8 cm of plastic scintillator inside it.
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15. How many cosmic rays can hit the detectors at once?
The exact value can vary and depends on the energy of the cosmic rays but a typical value is a few hundred per second. You can even see this if you look at the screen of CHICOS. The detector A and B gauges show the number of hits per second.
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16. Which time of day does the most stardust hit the pod?
The time of day does not affect the number of cosmic rays hitting the detectors very much with one important exception. It might be thought that since the Sun produces many of the cosmic rays, the detector should measure many at noon and fewer at midnight. However the cosmic rays that come from the Sun bounce around in the solar system's and the Earth's magnetic fields; they get all twisted around and don't remember which way they came from. So these cosmic rays form a constant thin rain that falls uniformly around the Earth all the time. The important exception occurs when it is recognized that the time of day is really a way of describing how much the Earth has spun since the start of the day. So if we saw a lot of cosmic rays being detected everyday at the same time of day it would indicate that the detector was pointing in a particular direction in space, which would be the source of the cosmic rays. However, if we were looking at a cosmic ray source outside the solar system, the "high flux" time of day would gradually shift throughout the year (as the Earth moves around the Sun). This is something that the researchers are hoping to find but is not directly connected with the Sun itself as a cosmic ray source.
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17. What will happen if there's no sun out or if it's raining, hailing or snowing?
Sometimes some of our information is weather dependent. For example, coincidence rate will go down as pressure goes up (this is due to there being more air molecules so more of the cosmic rays get filtered out).
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18. What is a shmoo in the CHICOS program?
The white hat-shaped detectors are called Shmoos. They have this name because of their resemblance to the Li'l Abner cartoon creatures.
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19. What is the CHICOS [software] programming for?
Each CHICOS computer is constantly running a program to record the incoming data from the cosmic ray detectors, and to display some of the data so a user can tell if things are working properly. You can learn more about the graphs and other displays by browsing the software's user manual.
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20. Why does the glowing purple thingy [scintillator] glow purple instead of red or green?
That depends on the chemistry of the plastic molecules that make up the scintillator material. However, the scintillator material is engineered to produce a fairly pure color (wavelength) of light, and a color that can be easily detected by the photomultiplier tubes we use.
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21. What would happen if you turn a computer off?
We assume you want to know what happens if you turn off the CHICOS computer. If we have done our job properly, and provided you shut it down properly and don't actually unplug the power, the computer will restart itself and restart all the proper CHICOS programs for taking data. Please don't turn off the computer, though.
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22. Why are there two detectors instead of one or three?
We designed this experiment to use the smallest amount of equipment that would actually give us the information we need. We can't get away with just one detector, though. We need two detectors so we can begin to tell the difference between cosmic ray showers and plain old low-energy cosmic rays; a cosmic ray shower centered near your site will set off both detectors at once.
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23. How did you make the detectors?
We got a lot of the equipment from a previous experiment at Los Alamos National Lab in New Mexico. However, the detectors still had to be assembled, and the electronics needed to be built. We didn't do this -- you did! That is, much of the equipment building and testing has been done by high school and middle school students in the CHICOS summer program. Perhaps you can participate and find out for yourself.
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24. Is it hard to make a computer?
We're not sure this is a CHICOS detector question. We don't make the computers we use in CHICOS -- we buy them, much as you or your school buy the computers you use.
Whether it's hard to make a computer depends on what you mean by "make." Many kids probably have experience buying individual computer components and aseembling them inside a case to "make" a computer. But if you had to "make" the circuit boards, or if you had to "make" the actual processor chips???
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25. Why does the memory disappear if the computer is turned off?
Again, this is not really a CHICOS-specific question. Computer memory is established by keeping a little bit of voltage on a particular device inside the computer hardware. It takes electricity to maintain that voltage, which maintains the memory. Storing something on a hard drive ("saving" a file) uses more energy to begin with but doesn't need continuous electricity to maintain the stored information.
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1. Will they make noise when it rains?
2. Does it feel like Styrofoam?
3. How do the cosmic rays get information from a satellite (If there is one).
4. Does Theresa enjoy her job?
5. Can we have a field trip there?
1. Will they make noise when it rains?
Answer
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2. Does it feel like Styrofoam?
Answer
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3. How do the cosmic rays get information from a satellite (If there is one).
Answer
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4. Does Theresa enjoy her job?
Answer
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5. Can we have a field trip there?
The CHICOS group is happy to show our lab at Caltech as a field trip or part of a class field trip. Teachers should contact us to discuss plans in advance.
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