Guiding Question: What are the factors that affect the appearance of impact craters? How do scientists use craters to tell the relative age?

Hypothesis: The bigger the crater the larger the meteor that caused it was. Scientists can't tell how old meters are.

Materials:

• safety goggles
• tray
• flour
• notebook
• spoon
• small and large marbles
• ruler
• excel and word
  

Procedure:

Data Graphs:



DATA ANALYSIS:

From looking at this bar graph, I can see a constant increase, and the larger the crater and the bigger the diameter the higher the marble that created it was dropped at. A pattern I noticed was that the depth of the crater and the diameter was almost always the same. If the marble was dropped from 6 meters, it would cause an increase in both the diameter and depth. That's because the marble has 6 meters space to be acted upon by gravity and to gain speed, so it's going to crash with an even greater speed in the flour. When we dropped the marble from 2 meters the diameter was 3.0 cm and the depth was 2.8 cm. If we were to do it with 6 meter drop my estimate is that it would be 9.0 cm in diameter and 8.4 cm in depth, which is three times the 2 meters. However, if we were to do this we would have to get a deeper testing tub, since the marble would reach the end of the tub easily, and then we wouldn't get accurate measurements.

CONCLUSION:

From this lab I learned that the higher up the marble is dropped from, the larger the crater is going to be. When we tested this both the depth and the diameter of the crater kept increasing. This matches my hypothesis, since I thought that the bigger the crater the higher the drop, and also the bigger the meteor or in this case marble. I also noticed that the diameter and the depth of the crater are pretty similar, and that often they're exactly the same size, or with a very little difference. I wonder if this actually relates to real life. Otherwise it might only be because we used a sphere (marble), which is a regular shape, so therefore it would be the same height and depth. A meteor probably would be more oval and irregular shaped. Also, the pieces broken off from it might form smaller craters nearby, which the marble doesn’t. I can now conclude that the factors that affect the appearance of craters are the speed they collect, the size, and the shape.

‘Dead’ Galaxies Aren’t So Dead After All

By ScienceDaily

http://www.sciencedaily.com/releases/2011/05/110531155357.htm

Scientists have found that new stars are being made in galaxies that we thought were dead! In four different galaxies, each about 40 million light years away, and each light year approximately 5.9 trillion miles, new starts are being reborn!

"Scientists thought these were dead galaxies that had finished making stars a long time ago," U-M research fellow Alyson Ford said. "But we've shown that they are still alive and are forming stars at a fairly low level."

There are two types of galaxies, the spiral galaxies and elliptical galaxies. Spiral galaxies, such as out Milky Way, have cold, dense gas, from which new stars are formed. However, stars in elliptical galaxies orbit around randomly and have almost no cold gas, and up until now to formations of stars were known. However, astronomers have found out a way to look at all the light from solar systems concentrating not only on the whole galaxy at once but on specific stars, using the Hubble Space Telescope. This telescope makes it possible for us to see stars being created, even at the rate of one per 100,000 years.

"We were confused by some of the colors of objects in our images until we realized that they must be star clusters, so most of the star formation happens in associations," Ford said.

A star we have observed is the star formation Messier 105, an elliptical galaxy 34 million light years ago. Ford and Bregman have discovered a single star 10 to 20 times larger than the mass of the sun. In Messier 10, new stars are being formed every 10,000 years. Our next mystery to solve is what the gas that forms stars actually is.

I thought that this article was really interesting, and it might be what future space research is going to be based on. I think that it’s incredible that “dead” galaxies just turn out to be alive, even if at a very slow rate. If it’s true that stars are created wherever there’s the cold, dense gas, then the universe might never end. Also, if humans managed to discover what this star- making gas was made up of, we might be able to discover exactly how stars are made. Then we could re- create the gas, and when our sun dies we could make another star just as close as the sun, to continue living and receiving light and heat. Also, if these galaxies really were dead, and then became alive, maybe this gas could serve as a good medicine for humans. (or maybe they were just unknown to humans) Another thing that fascinated me while reading this article was that stars can take up to 100,000 years to create, at least in Elliptical galaxies. It would take a long waiting to see the process, and a lot of gas.

Moon Phases

What did you notice about the phases of the moon?
I learned that depending on which angle the sun hits the moon, it is visible to us on earth in different ways. We only see the part of the moon illuminated by the sun. There are 8 phases of the moon, the main ones being full moon, first quarter, full moon, and third quarter. Below is a picture I drew of what I learned from this activity:

Why do we see different parts of the moon each night?
The reason we see different parts of the moon each night is because the moon is constantly orbiting around us, even during daytime. Every night, when it is visible to us, it has orbited to another angle. Therefore, the way we see the light on the moon is slightly changed. We can only see a full moon when the moon is right behind the earth, since that is when the sun shines on the moon at an angle so that all the light is visible to us. See picture below:However, when the moon is right in front of the earth, to us it's a new moon, since the light on the moon reflected to the sun isn't visible to us on earth. See the picture below on wave simulator:


What is a lunar month?
A lunar month is 29.53059 days. That is when the moon has completed its cycle once, and has gone one full time around the earth, a lunar month. Once the moon has completed its cycle, it starts a new one, and orbits the earth again.

How does the moon, sun and Earth interact to cause so many things to occur?

The moon, sun and Earth interact in many ways and basically make up our lives. The Earth revolving around itself creates our days and lives, and orbiting around the sun creates the seasons. The moon creates the tides on Earth, including spring and neap tides. The sun's light and heat makes life possible on Earth. Eclipses happen when the earth and the moon block the light of the sun from each other, so all three are needed for eclipses to happen. These three large masses orbiting around each other in space make our lives possible.


What causes an eclipse and tide?

An eclipse is when the Earth's shadow hits the moon or when the moon's shadow hits the sun. Either way, from Earth either the view of the moon or the sun is blocked. During a solar eclipse the moon is blocking the sun's light, being in directly between the sun and the earth. During a lunar eclipse, the moon is right behind the shadow of the earth. That means that the Earth is in between the moon ad the sun, so the sun's light doesn't reach the moon. Therefore, from earth we can't see the moon.

Tides are caused by the pull of the moon's gravity on Earth. The Earth's oceans are being pulled either towards the moon, or away from it. Below is a picture of how the moon creates the tudes to happen, and spring and neap tides. Neap tides 0ccur when the suns pull is on one side of the earth and the moon's pull is on the other. It creates a sort of a balance between pulls of gravity, so there is the least difference between between tides. A spring tide happens when the moon and the sun are one quarter on either side away from each other, putting their forces together. Then the difference between high and low tides is the greatest.

Reasons for the Seasons Lab

Analyze and Conclude

1. When it is winter in the Northern Hemisphere, which areas on the Earth get the most concentrated light? Which areas get the most concentrated light when it is summer in the Northern Hemisphere?

When it is winter in the Northern hemisphere, the light from the sun is going to be directed towards the Southern hemisphere. When it is summer in the Northern hemisphere, the light from the sun isn’t going to shine as much on the Southern hemisphere since it isn’t directed on it, and it would be winter there.

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 the area is only hit by dimmer light, and the squares are stretched out and look like rectangles. The light is faint. However, in summer, when the light is more direct, the light is a lot stronger and the squares are square looking.

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?

Where the light from the flashlight (sun) hits more directly, the squares are more square- shaped. However, right above and below the squares are more stretched out and rectangular, and the light isn’t as strong which means that it is indirect light. The normal sized squares receive more light than the stretched out ones, since all the light from the sun is concentrated in one place. With the stretched out squares the light is being stretched out and is growing fainter, so therefore those areas of the globe are cooler.

4. According to your observations, which areas on Earth are consistently coolest? Which areas are consistently warmest? Why?

The areas closest to the equator are constantly warmest, since they are in the middle and always get at least a little light from the sun. The top and the bottom part of the earth, however, don’t always get a lot of light. This makes the North and the South Pole the coldest places on Earth.

5. What time of year will the tooth pick’s shadow be the longest? When will the shadow be shortest?

During the winter the toothpick’s shadow would be longer, and it would be shorter during summer. That is because during winter the light is coming at the toothpick from a less direct angle, making the shadow longer than if it was coming straight above it.

6. How are the amounts of heat and light received in a square related to the angle of the sun’s rays?

When a square is under direct sunlight it appears like a square and isn’t stretched out at all like the squares around it. It then receives the most light and heat from the sun. The squares that are stretched out receive only limited light and heat, and squares with no light that you can’t even see receive little or no light and heat. Therefore, the more direct the sunlight is to the square the lighter and warmer it will be.

7. Use your observations of an Earth-sun model to write and explanation of what causes the seasons. How does the tilt of Earth’s axis affect the light received by Earth as it revolves around the sun?

The earth is tilted at a 23.5 degree angle as it orbits the sun. It revolves on itself once every 24 hours, and around the sun every 365 days, or a year. Since the earth is tilted, different parts of the earth hit the sunlight at different time periods of the year. When the light from the sun directly hits the northern hemisphere or above the equator it is summer there and winter in the southern hemisphere, and vice versa. When the earth has completed a full circle around the sun, it starts off from zero again, and repeats summer and winter. We have split this cycle into four seasons, summer, fall, winter and spring, to better understand and keep track of the seasons. That is how the 23.5 degree angle of the earth’s tilt affects the seasons.

Waves unit reflection

This is a bubbl.us I made about everything I have learned in this unit about waves. (or the main ideas)

The study and use of waves affects societal well- being in many ways.

By studying water waves we can predict tsunami, using buoys to detect changes in water levels and strong water currents and waves under the ocean. By predicting tsunami we help people prepare themselves against it and save millions of lives. Seismic waves are also a way of predicting natural disasters. By detecting waves in the earth using an instrument called a seismograph that we also learned about, we can see if any particular large waves are approaching, and in this way too we can prepare and protect ourselves against natural disasters.

By studying waves humans have also found out about the electromagnetic spectrum. Using Gamma rays, we can irradiate our food, meaning take out harmful bacteria and illnesses to keep us safe. This helps us stay healthy, or at least that’s what we think so far. (see previous blog post.)

By studying waves we have also discovered the benefits of sound, which are today used in our everyday lives. From studying sound, we have discovered how to break the sound barrier, enabling our rockets and fast of transportation to travel faster than the speed of sound. From sound we also now know about noise pollution, and about damage it causes to your hearing. From this we have also been able to investigate solutions, to benefit society. (see essay on blog) Overall, the use and study of waves has definitely affected societal well- being and the world would be a completely different place without all types of waves.

What did you learn during the unit? (Looking at the picture you drew-how has your knowledge changed?)

Looking at my picture from the beginning of this unit, my knowledge of waves basically started at 0, since I drew a beach and a big wave at sea. Now, my knowledge has expanded a great deal, and I can name all types of waves and give some basic information about them, such as visible light waves, microwaves, gamma rays, sound waves, water waves and seismic waves. I can also locate different parts of waves such as crests (top) and troughs (bottom). I now know a lot of wave properties too, such as frequency, pitch, wavelength, ext. We have also learned about instruments, and how they use waves to produce sound. Mainly, it is only the string instruments that produce sound using waves, but all the instruments we have produce sound waves. Some facts I have learned are; waves travel faster in solids than in liquids, and faster in liquids than through gas,the way sound waves bounce back and forth in a room is called acoustics, we use things called cones in our eyes to see the visible light waves and the color with the longest wavelength is red and the color with the shortest wavelength is violet.

What did you like?

Something that I really liked and that is memorable to me from this unit is all of our labs. My favorite lab was the one with the tubs filled with water, and when we observed how water waves traveled. Then we also added one and later two barriers, and saw how the wave would diffract. It was kind of weird and fun watching two waves crossing into each other but still having their own shape , so sort of two things happening at the same time. We also had a lab with tuning forks, in which we compared sound waves. We saw how the density of the materials we would bang the tuning fork on would transmit the energy and cause different sounds, and have the waves reach your ear at different times. We also had a lab in which we tied a string to the ground and shook it creating waves, which we then measured the wavelength of. I think that it was fun and a good way to start off the unit, since waves can be really confusing when starting from scratch, like I did.

What would you change or add for next year's grade 7 students?

I don’t think that I’d do any major changes to the wave unit for next year. I think that it’s a fun balance between trying out things on our own through labs and textbook work. It sort of makes waves fun but serious. I think that since waves is a unit that we can actually relate to and see with our own eyes in everyday life it’s good that we do labs, and we should include all the activities that we can. Something else that I think we should have done is to have spent some more time on the electromagnetic spectrum waves. It felt kind of rushed, and I think that maybe we should have had some more readings or informational things too, since we only really focused on our own presentations. Another thing that we have done and next year’s 7^th grade students should continue doing is watch Bill Nye science clips, since they’re fun and informative!