Impactor Crater Lab

Craters are all around us! We can find them on both the Earth and the moon. They can either be created by impacts from meteors or volcano tops blowing off. This lab focuses on Impactor Craters.

SOME KEY TERMS:

floor: bowl shaped or flat, characteristically below surrounding ground level unless filled in with lava.

ejecta: blandet of material surrounding the crater that was excavated during the impact event. Ejecta becomes thinner away from the crater.

raised rim: rock thrown out of the crater and deposited as a ring-shaped pile of debris at the crater's edge during the explosion and excavation of an impact event.

walls: characteristically steep and may have giant stairs called terraces.

rays: bright streaks staring from a crater and extending away for great distances. See Copernicus crater for another example.

central uplifts:mountains formed because of the huge increase and rapid decrease in pressure during the impact event. They occur only in the center of craters that are larger than 40 km diameter.

GUIDING QUESTION:
What are the factors that affect the appearance of impact craters? How do scientists use craters to tell the relative age of them?
HYPOTHESIS:

I think that the younger the crater is, the rougher it will be, because it might erode over time. Factors that might affect the appearance of impact craters is the speed the meteor is coming at, the heat of it, the mass of the meteor, and the size of the meteor.

MATERIALS:
safety goggles, tray, flour, notebook, spoon, small and large marbles, meter stick, ruler, excel and word.
PROCEDURE:
1. Put on goggles and apron. Fill the pan with 2.5 cm of flour.
2. Drop a small marble into the flour. What did you observe? Drop another marble again. What happens when they overlap?
The marble creates a small impact. You can hear it and it sends waves throughout the whole tub. The ejecta goes a little farther than the marble all the way around. When they overlap, they overlap on debris and create a small mound. In real life, this could be extremely disastrous. It also creates a bigger crater in a stranger shape.
3. Drop the larger marble into the flour. What did you observe? Drop another marble again. What happens when they overlap?
When you drop the larger marble, it creates a much larger impact and the ejecta flies everywhere. When they overlap, they create a half-moon type shape.
4. Think about the guiding question. What does affect the appearance of an impact crater?
Just from dropping the two different-sized marbles, I can see that the size of the meteor definitely affects what the crater looks like. The larger the marble, the bigger the crater, and the deeper the impact is.
5. Decide on which materials you will use and collect them all to take to your station. You will make a model to test the guiding question.
6. You will need to collect some qualitative (using your senses to make observations) and quantitative-numerical data (Height of drop, mass of the object, diameter of crater, depth of the crater, length of ejecta - if possible to measure, etc...)
7. Make a data table (below)
8. Run your lab according to the method provided.
9. You may wish to take pictures of each impact to use later in a blog post, or you may sketch the results in your notebook.
10. Collect the data needed and enter it into the table.

Trial	Height of Drop	Diameter	Length of Ejecta	Depth of Crater
1	30	1.9 cm	0.1 cm	0.7 cm
2	30	2 cm	0.3 cm	0.4 cm
3	30	1.7 cm	0.3 cm	0.7 cm
average	30	1.87 cm	0.23 cm	0.6 cm

Trial	Height of Drop	Diameter	Length of Ejecta	Depth of Crater
1	60	3 cm	0.7 cm	4 cm
2	60	2 cm	0.6 cm	1.8 cm
3	60	2 cm	0.7 cm	2.4 cm
average	60	2.34 cm	0.67 cm	2.73 cm

Trial	Height of Drop	Diameter	Length of Ejecta	Depth of Crater
1	90	2.5 cm	1 cm	2.7 cm
2	90	2 cm	0.5 cm	2 cm
3	90	2.3 cm	0.7 cm	2.3 cm
average	90	2.27 cm	0.73 cm	2.34 cm

Trial	Height of Drop	Diameter	Length of Ejecta	Depth of Crater
1	200	2.1 cm	1.2 cm	3 cm
2	200	2.4 cm	0.9 cm	2.7 cm
3	200	2.8 cm	1 cm	2.8 cm
average	200	2.43 cm	1.03 cm	2.83 cm

DATA ANALYSIS:
1. Is your hypothesis about what affects the appearance and size of craters supported by test data? Explain why or why not.

I think that my hypothesis covers most of the factors in the appearance of craters, just the one that I didn’t mention that I realized during this lab was when two craters overlap and create a different-shaped crater.
2. What does the data reveal about the relationship between crater size and velocity of impactor?

Well, we didn’t necessarily test the impactor velocity, but the farther away from the tub the impactor starts, the more speed it gains. This works well with our data, because the further away we dropped the impactor, the deeper the crater was, and it tended to have a bigger diameter too.
3. What does the data reveal about the relationship between ejecta (ray) length and velocity of impactor?

The same thing applies to this – the greater the velocity is that the impactor is coming at, the greater effect it’s going to have on the surface. In this case, it creates a lot of ejecta.
4. If the impactor were dropped from 6 meters, would the crater be larger or smaller? How much larger or smaller? Explain your answer.

It would be a lot bigger. This is because it has time to gain speed as it falls, because it is a greater distance than 90 cm, for example. Then, when it hits the surface, it creates a deep and big crater, with lots of debris (ejecta) coming from it.

CONCLUSION:

My hypothesis was relatively correct. The appearance of impact craters is affected by the velocity of the impactor, the mass, size, and weight of the impactor, where the impact crater is, and whether the crater overlaps. The last factor is one that I just learned this lab. It’s true that most craters look like circles – we can see that when we look at the moon. However, when two impactor craters overlap, they create a unique half-moon type shape. My original hypothesis was that scientists detect how old craters are by whether they have eroded a lot or not, but the overlapping of two impactor craters is another more fool-proof way that scientists figure out how old they are.
FURTHER INQUIRY:

Unfortunately, for this lab I think we had a couple of errors in the data. Measuring the depth of the crater and the ejecta was difficult, because we had to make sure that we weren’t going to mess up the crater. However, just by looking at the experiments we were doing, we were able to tell what would happen in a real life situation when a meteor comes hurtling at the earth. Some craters are larger than others because the meteor that comes is either larger than normal, or is coming at a much greater speed. Another thing that might happen is two craters overlap, creating a very large ‘double crater’. It also has to do with the mass. Basically, anything that will make the meteor larger or heavier will cause a bigger crater. You could test this by dropping the impactors not only at different heights, but also just throwing it hard, making it faster. Or you could test this by comparing two different impactors, which we did at the beginning of this lab, with the smaller marble and the larger marble. The surface that the meteor hits could also have something to do with the appearance of the crater – if it’s very impressionable ground, the meteor will undoubtedly have a greater effect on it than if its solid rock.

Current Events - Astronomers Witness a Star Being Born

There's been a new discovery - astronomers have seen the youngest known star developing!It hasn't yet become a true star, but it has just started pulling in matter from surrounding envelopes of dust and gas. Scientists are calling this star L1448-IRS2E. They think that this star is in between the prestellar phase and the protostar phase. The prestellar phase is when a very dense region of a molecular cloud begins to clump together, and the protostar phase is when gravity has pulled enough stuff together to form the core of the star. This star is located around 800 light years away, still within our galaxy. It is in the Perseus, a star-forming region.

Scientists want to use their new 'Herchel' space telescope to look for more forming stars so that they can learn more about how stars grow and evolve. 'Stars are defined by their mass, bu we still don't know at what stage of the formation process a star acquires most of its mass,' said an assistant professor of astronomy at Yale, Hector Arce. This is one of the main things that they are trying to find out more about.

I think this is a great discovery! It just shows how much science has evolved over the years. It used to be that finding out about our solar system was huge, but now scientists can find out about stars in the Milky Way and even beyond. In a while, we'll be able to find out even more than that! Witnessing a star being born is also special because it will teach scientists a lot more about how a star is born, how it grows, and how it evolves.

http://www.sciencedaily.com/releases/2010/06/100617132226.htm

Lunar Phases

What did you notice about the phases of the moon?

I noticed that phases of the moon don't really depend on the amount of sunlight shining on it, which is always the same, but it depends on where we are on the earth, and where the earth is in relation to the moon and the sun. I also noticed that the phases of the moon are constantly changing. The full moon comes back every 29.7 days, and that never changes, the phases are constant.

Why do we see different parts of the moon each night?

We see different parts of the moon each night because the earth is revolving at the same time as the moon is orbiting the earth.

What is a lunar month?
A lunar month has the length of 29.7 days. This is from one full moon to the next, as mentioned in the first question.

What are phases?

The phases of the moon are basically the different parts of the cycle that the moon goes through. They go like this:

New Moon

Waxing Crescent

First Quarter

Waxing Gibbous

Full Moon

Waning Gibbous

Last Quarter

Waning Crescent

and so on.

What causes them??
Phases are caused by the moon revolving around the earth at the same time as the earth is revolving around the sun. Also, the earth is rotating on its axis at the same time too. The way that the sun falls on the part of the moon that we see is what cause phases. This also applies to tides - they are caused by how the gravity of the moon and the sun and the earth all relate to each other.
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Reasons For the Seasons

In class we did a lab about seasons where we took a styrofoam ball as a model of the earth, and we're supposed to answer questions about it.
1. When it is winter in the Northern Hemisphere, which areas on Earth get the most concentrated light? Which areas get the most concentrated light when it is summer in the Northern Hemisphere?
The most concentrated light is in the Southern Hemisphere, because the more concentrated light is, the hotter the weather will be. And while it is summer in the southern hemisphere, it has to be winter in the northern hemisphere.
2. Compare your observations of how the light hits the area halfway between the equator and the North Pole during winter and during summer.
During winter, light doesn't hit that area very much. As we saw in our experiment with the grids, the squares from the grid on the northern hemisphere looked like rectangles. This means that the light was less concentrated there.
During summer, the light is shining directly on the sphere, and the grids look like squares, not rectangles. This means that it is a higher concentration of light.
3. If the squares projected on the ball from the acetate become larger, what can you infer about the amount of heat distributed in each square?
That means that there's less heat distributed in each square.
4. According to your observations, which areas on Earth are consistently coolest? Which areas are consistently warmest? Why?
The North Pole and the South Pole are consistently coolest, because they are never directly in the sun. The equator is constantly warmest because it is in the middle and is always directly in the sun.
5. What time of year will the toothpick's shadow be longest? When will the shadow be shortest?
The shadow will be longest in summer, because the light is shining directly on it. In winter, the shadow will be shortest, because there is the least amount of light shining on it.
6. How are the amounts of heat and light received in a square related to the angle of the sun's rays?
The farther the light is angled away from the square, the less heat and the less light there is.
7. Use your observations of an Earth-sun model to write an explanation of what causes the seasons.
The seasons are basically caused by how the light of the sun is directed on the Earth. The more direct the sunlight is hitting the earth, the hotter and the lighter it is. This is when Spring and Summer come into play. The less direct the sun shines on a certain part of the Earth, the colder the season - this is when Fall and Winter come into play.

Waves Unit Reflection

How does the use and study of waves affect societal well-being?

The use and study of waves affects societal well-being in many different ways. Although we may not realize it, waves are all around us – there are more types of waves than the ones we find on the beach. When we listen to music, we are in reality just listening to a bunch of waves. When we see sunlight reflecting off of someone’s glasses, it’s actually a wave that’s being reflected. We microwave our food with waves! Without waves, we would be nowhere. We wouldn’t be able to see anything, we wouldn’t be able to hear anything, and we would have no technology. Without waves, we wouldn’t have lives.

We learned all about waves in this unit. There are several types of waves – electromagnetic waves, sound waves, and seismic waves are the main ones we learned about after we learned about the basic components of waves and how waves react to their environment.

My knowledge has changed very much. Learning about waves around us is pretty cool because now whenever I microwave something, I think “hey, microwaves are actually pretty strong! I probably shouldn’t press my face against the microwave.” For my project, I did Ultraviolet Rays, and that also made me be more cautious about being in the sun too long, and what would happen if I was. There’s more to waves than just the typical scientific stuff – they’re all around us, and they’re very important in our lives.

When we learned about seismic waves, we looked at different earthquakes that had occurred around the world. Although I already knew about how earthquakes were created and the damage an earthquake can cause, I learned the specifics in class. I also learned a whole lot about tsunamis that I didn’t know before.

Next, we learned about sound waves. We learned about how sound affects us, about how it travels, and how bad noise pollution can be for us.

Lastly, we learned about electromagnetic waves, and the electromagnetic spectrum. Everybody did a presentation on a type of electromagnetic wave, and that way the whole class learned quickly. We learned about radio waves, microwaves, infrared waves, visible light, ultraviolet rays, x-rays, and gamma rays.

I liked this unit a lot, actually, because it branched out to a bunch of different topics and we were constantly learning how it related to our lives. We learned a lot of science that wasn’t necessarily just about waves, too. I liked the Tsunami Essay, because it opened my eyes to some of the things that are going on in the world that isn’t happening here.

I think that this was a really good way to learn about waves. For next year’s unit, maybe the electromagnetic spectrum should be a bigger part of the unit. The presentations were great, but it would have made it even more interesting if we could learn about each specific electromagnetic wave, review the presentations. That way the students can keep the information a little more permanently imprinted in the brain.

Food Irradiation

We had a debate in class this month about food irradiation. Neither side really won, but we came up with a good proposal to the FDA:

Dear FDA,

The students of ISB’s proposal to you is that irradiation must be proven to be healthier, without hazard and, in the long run, better for our economy before irradiated food is allowed to be produced and put into stores all around the world. It must also be clear that the food the customers are buying irradiated food.

These were some of the pros and cons:

Cons:

environmental destruction

costs a lot!

problems have been discovered in animals that ate irradiated food (premature death, rare form of cancer, liver damage, vitamin deficiencies)

masks and encourages filthy conditions in slaughterhouses (kills bacteria but does nothing for feces, urine, pus, and vomit)

doesnt kill the pathogen that causes mad cow disease, either

destroys vitamins (80 % vitamin a in eggs, etc.)

can change the flavor, odor and texture of food (pork turns red, beef smells like wet dog, fruits and veggies become mushy, eggs can lose their color and become runny

disrupts the chemical composition of everything in its path

forces farmers and ranchers out of business, even WORSE for our economy

high energy gamma rays create free radicals in the cells they penetrate which is implicated in heart disease

new compounds are formed radiolytic products not sure whether they are toxic or not

food poisoning bacteria could become resistant to irradiation over time just like with antibiotics

kills good bacteria

limited amount of food they can irradiate

doesnt work on seafood

PROS

Millions of americans get sick yearly from spoiled food

Destroy's bacteria and echanes shelf life

does not change the content of foood

NO harmful substances are created in the food

destroys other harmful substances in the food

Little or no heating frozen foods

can treat pakaged or frozen foods

no chemicals used for preservation of fresh foods

low energy requirements

comprable change in nutrional value

Eating irradated food DOES NOT present long term health risks

Irrdiation DOES not make food radioactive

Can eliminate food germs

irradiation can kill substaantially reduce the number of potentially dangerous organisms

in foods. estimate range from 90 to 99.9 precent

Irradition can kill insects and pests infesting foods such as grains and flours without leaving

chemical residues

Irradiation can be used to sterlize food immune-compromised individuals such as Aids patients

Irradiation has been deemeds safe by various govermental agenicies

Proponets of irradiation compare the changes in food caused by iiradion to

products created by other processes such as cooking ar freeze-drying

Irradation delay's ripening and sprouting so food can be stored longer

There is no potential for enviromental impact because the radioactive materials are fully enclosed

and are returned to the manfacter for recycling or diposal

Good safety and record for existing irradition facilities

without irrated food 76 million would be sick from food sickness

between 5 and 7 billion dollars are wasted on spoiled food

In this case, I don't think science was such a good invention. Food irradiation was invented with a good purpose in mind - to address a global food problem. However, in my opinion, there are simply too many things that could go wrong. I think that before food irradiation is thought of as the solution to all of our world's food problems, it needs to be completely foolproof. Nothing can go wrong, because this is food we're talking about. Food is something that every single human being needs to survive, and if the food is contaminated, then our whole world could potentially collapse. If there are two containers of food at the supermarket, one irradiated and one not, I would definitely pick the one that isn't. It's a type that I can trust and has essentially been proven safe. Irradiation hasn't been proven safe, so I wouldn't want to buy it until it is 100% safe.

My thinking didn't really change throughout the debate, because I was assigned to talk about the cons of irradiation and I really think that irradiation isn't a good idea at the moment. Before we did this activity, I actually knew nothing about food irradiation before we did this activity, so it really opened my eyes up to something that's going on in the world that I wouldn't have known about otherwise. I did like the activity, it was fun to argue for my side of the debate and it ended up being really informative.