Harry

**SEARCH FOR LIFE OF MARS- ENTRY 1: ELECTRONICS AND COMPUTERS**
Many different signals are in most of the electronics we use like TV’s, CD players, radios, and telephones. There are two different signals: Analog signal and Digital signal. An analog signal is a signal that varies smoothly in time. A digital signal does not vary smoothly, but changes in jumps or steps. They are different because an Analog signal such as a TV which transmits information, varies smoothly in time whereas a digital signal such as a CD player doesn’t, instead it changes in jumps or steps. Semiconductors are found in your electrical devices as well and you might be wondering how they help the devices and what the purpose of a semiconductor is in an electrical device. First off, a semiconductor is an element that is a poorer conductor of electricity than metals but a better conductor of electricity than nonmetals. Two types of semiconductors can be put together to create electronic components that can then control the flow of electricity in the circuit. The two types of semiconductors are p-type and n-type. An n-type can give electrons, and a p-type semiconductor can receive electrons. A diode is a solid state component that allows the current to flow in only one direction. A diode is used for converting alternating current to direct current. A transistor is a solid state component that can be used to amplify signals in an electronic switch. A transistor can be used in an electronic switch and electronic signals cause a transistor to allow current to pass through it or to block the flow of current. An integrated circuit or chip contains large numbers of interconnected solid-state components and is made from a single chip of semiconductor material like silicon. The advantage of an integrated circuit is that it stores thousands of diodes and transistors on a  chip which is what allows our computers to be so small.

Electronic devices are extremely important when your job is to travel to Mars to search for life. We need computers to record data of what you are learning on Mars, and you need it to communicate as well. You need to communicate with Earth and the space shuttle on Mars in order to send back information and data. You would also need cameras to see what’s happening and be able to watch it over again. Robots were probably involved in making the space shuttle which is a very advanced piece of technology and was programmed by a computer. I can’t imagine an expedition to Mars without the use of technology because it provides so much and the technology today is getting more and more advanced.

// Ms. Mc - Good overview of electronics and ideas about how we might use electronic devices on our mission. The only improvement would have been a little more detail about what specific electronic devices you might use to search for life on Mars (i.e., rovers, lasers to sample rocks, etc.). 9.5/10 //

__4/1/11__ __Entry #2__

Rocket History

In the first century, the Chinese had reportedly come up with another form of gunpowder. It was made from saltpeter, sulfur, and charcoal dust. During religious festivals,a way to create explosions in the middle of them was by filling bamboo tubes with the mixture and then throwing them into fires. Later on, the Chinese began to experiment with tubes filled with gunpowder. For one type of experiment, they attached bamboo tubes to arrows and then launched them with bows. Later on, they found out that the gunpowder tubes could be launched just by the power created from the escaping gas. This was the true invention of the rocket.

Chinese Fire Arrow In 1898, a Russian schoolteacher, Konstantin Tsiolkovsky thought of an idea which involved the rocket in exploring space. Tsiolkovksy suggested that in the rockets, liquid propellants were to be used in order to reach a greater range. Tsiolkovsky stated that the speed and range of the rocket were limited by the exhaust velocity of escaping gases. Tsiolkovsky was a genius for creating his ideas and theories and is still called The Father of Modern Astronautics.
 * Picture 1. A Drawing of a Chinese Fire Arrow**

On October 4, 1957, the news was released that a satellite orbiting the earth was launched by the Soviet Union. This then led to more ideas and innovations of rocketry and satellites. Later on, the United State launched a satellite of its own similar to the Soviet Union’s satellite. Explorer I, was launched on January 31, 1958. This is what led to the creation of the space program, NASA (National Aeronautics and Space Administration). NASA’s goal was to explore around space and collect data and research about planets and the solar system. Astronauts were later sent into space and landed on the moon.

Today, our world’s technology is rapidly increasing and new innovations are created which will let the world of Astronomy and rockets improve.
 * Picture 2. Satellite orbiting around Earth**

Ms. Mc: Very good summary of the history of rocketry. Good digrams as well. Please create captions for your drawings/photos with the Figure # and title. 14.5/15

__4/5/11 Entry #3__

__Rocket Flight Simulation__

media type="custom" key="8971142" __1) Turn on sound to hear liftoff__ __2) Click on__ Green Flag__ to begin simulation 3) Click on Red stop circle to pause or stop the simulation

Log Entry #4 4/13/11


 * Picture 1: Picture of rocket parts used on Rocket to Help it Fly**

During the rockets flight, all these rocket parts are used in the process. The Nose Cone is what lets the rocket glide through the air which you can tell from its pointy shape. The body tube is what keeps the nose cone connected to the rocket during flight and is a pointy tube which makes the rocket more aerodynamic. When the rocket reaches its peak or apogee, it then starts to descend and the ejection takes place and lets out the recovery system from the nose cone which is what gets the rocket back to earth safely and efficiently. During the flight, the recovery wadding, which is inside the rocket, is what protects the recovery system when the engine is firing so it doesn’t blow up. The launch lug, which is located between the fins is what helps the rocket glide straight off the launch pad and straight up into the air. The 3 fins on the rocket, which help the rocket glide in the direction it wants to go, are located near the bottom of the rocket. The motor mount which is inside the rocket, holds the rocket motor in place during flight. The rocket motor is what helps keep the rocket going during the flight and gives the rocket thrust.

//Ms. Mc: Very good definitions and labels. The recover wadding also is inside the rocket (-1/2). Also, it should be "Figure 1" instead of "Picture 1" in your caption and don't forget a title for your entry (-1). Good job! 18.5/20//

Log Entry #5 4/17/11

**The Relationship Between a Rocket’s Mass and its Apogee**

An experiment was conducted where seven groups each launched a model rocket into the air from a launch pad. The purpose of this experiment was to see the different stages during flight and to determine the relationship between the mass of the rocket and its apogee. At one point during the flight, inertia took place which is when an object in motion stays in motion until an outside force is acted against it. Inertia related to apogee in the flight because when the rocket arced over, inertia was the force that kept it moving and helped it arc over. An apogee is when the rocket reaches the peak during its flight and begins to arc over and it loses its momentum once it reaches its peak altitude. Air resistance is a force that acts in the opposite direction you are travelling. It was hypothesized that if the mass of the rocket was increased, then the rocket would not fly as high because the greater the mass of the rocket, the lower the rocket’s would be. Gun powder in the engine helped the rocket lift off from the launch pad. The initial thrust needed to launch the rocket during lift off stopped when the rocket arced over or performed its apogee. The thrust was needed to power the flight.

The rocket with the biggest mass was group three’s rocket with a mass of 44.5g. The group that had the second biggest mass was group two which had a mass of 44.4g. The group with the third biggest mass was group six which had a mass of 44.1g. Group five had a mass of 43.6g and group seven had a lower mass than group six’s by 0.1g which was 43.5g. The second to lowest mass recorded was 43.3g which was group one’s rocket. The group which had the smallest mass on the rocket was group four whose rocket had a mass of 42.2g. The different masses varied due to the amount of glue that was used on the rocket and how much paint was painted on the rocket. The group whose rocket reached the highest apogee during flight was group three, and it reached 81m. The group with the second highest apogee was group six with an apogee of 75m. Group one had the next highest apogee of 71m. Group five’s rocket reached an apogee of 70m. Group seven had their rocket reach an apogee of 65m. The group with the second to lowest apogee was group two with 55m. The group with the lowest apogee recorded was group four which had reached 53m.

In Graph #1 above, the data in the graph showed an upward trend going from left to right which demonstrates a direct relationship between the apogee and the mass of the rocket. In conclusion, the hypothesis was not confirmed correct because on the graph, the rocket with the smallest mass of 42.2g, reached the lowest apogee of all the rockets. Yet, the hypothesis stated that the lower the mass, the higher the rocket would fly. Also, the rocket with the most mass of 44.5g, reached the highest apogee of 81m. So therefore, it does not matter how heavy the rocket is in order for it to reach a high altitude. The rocket that reached the highest apogee on the graph had the most mass so the hypothesis, that the mass of the rocket would affect how high the rocket goes, was disproved. An example that could have caused incorrect data or error in the experiment was the weather. Some rockets were flown on different days than others, and there could have been bigger wind gusts causing the rocket to angle in a different direction. When recording the average altitude of the rocket, there were different angle gun measurers which affected the average altitude of the rocket. These were just some of the possible errors that could have been made during the experiment.

**Entry #6**

**What is a galaxy and how did they form?**

** A galaxy is made up of billions of stars, gas and dust. A galaxy is a disk of stars or a line of gas and dust. An example of a galaxy is the Milky Way. After the Big Bang, dark matter and matter began to clump together being pulled together by gravity. In this case, a Halo is a glob of stars that forms when a galaxy first collapses. ** Figure 1. Solar System and the Disk

**Which is older, the Universe or the Solar System?**

** The best estimate of the solar system is around 4.5 billion years old. The estimate of the universe is about 13.8 billion years old. The reason why the universe is bigger is because 13.8 billion years ago was when the big bang took place. The age of the solar system is determined by the radiometric dating of heavy elements such as uranium. There is very little information to explain why they think the solar system is younger than the universe. Therefore the universe is bigger than the solar system. ** Figure 2. Our Solar System and All Eight Planets

//Ms. Mc: Good pictures and captions. I'm a little confused about your answer to the 2nd question though. Are you trying to say that we don't know which is older the Universe or our solar system and that we only know that the Universe is bigger? (-1). You were to refer to the figures and explain them in your text (-1). Finally, don't forget to include a date and title for each entry (-1). 7/10//


 * Entry #8: The Programming Procedure for Challenge 1. **
 * 5/6/11 **

The purpose of this challenge was to program the robot so it would follow the lines on the floor without making any mistakes. For challenge one on the NXT lab, the robot was to do two right turns making a U shape. The steps took place like the following:


 * Figure 1. The Programming Procedure Performed for Challenge 1.**

Block 1. The movement block telling the C and B servomotors to move forwards for 3.5 rotations at about 75% power and then brake. The robot goes forward for about 0.5 meters and then stops.

Block 2. Movement block telling the C and B servomotors to make a 180 degree right turn at 75% power. The robot makes a right angled turn or a 90 degree turn but in order for it to make a right turn, 180 degrees had to be programmed into the robot.

Block 3. Movement block telling C and B servomotors to move forwards for 1.4 rotations at 75% power. The robot goes forward about 0.3 meters and then stops.

Block 4. Movement block telling C and B servomotors to make a 180 degree right turn at 75% power and then brake. The robot therefore makes a right angled turn. The robot makes a right angled turn or a 90 degree turn but in order for it to make a right turn, 180 degrees had to be programmed into the robot.

Block 5. Movement block telling C and B servomotors to move forward for 0.5 rotations. The robot goes backwards for about 15 centimeters and stops.

Block 6. Movement block telling C servomotors to make 4 rotations at 75% power.

Block 7. Movement block telling B servomotors to make 4 rotations at 75% power.

Block 8. Sound block telling robot to play applause at a volume of 75.

Block 9. Display block telling robot to display smile 01.