What is Physics? Chapter 1 Pg.5-13

The Search for Understanding Physics – branch of knowledge that involves that involves the study of the physical world. It studies a variety of things from the atom and subatomic particles to the universe The important part of any science is questioning and investigation. Why?? Best question you can ask in any area. Has led to a number of useful discoveries Atomic bomb, computer chips, golf clubs, etc.

The Wanderers Observations made about the ancient night sky: 5 very bright objects Follow set patterns of movement across the night sky throughout the year. Used to map out time and seasons. Seem to move westward for a period of time, then move back eastward What are they??

Early Science Around 2500 years ago, people were making observations of the earth, sun, moon , and other celestial bodies and trying to figure out what they were. What they were made of. Matter was thought to have four elements: earth, water, air, fire. We know this is not true now, combine those our and all we get is this guy  Motion was only straight line motion; elements moved toward their actual place.

Early Science People observed the “wanderers” did not follow this set pattern. Observations showed them to be perfect spheres and that they circled earth forever. This meant they could not be made of the four basic elements; a 5th element was added “quintessence. Up to this point there was no set way to observe and experiment

Galileo Galilei: “the father of modern experimentation Italian astronomer Developed first telescope First guy to really use “scientific method” Discovered: Planets has orbital moons Moons had surface features Multiple stars Galileo argued that the planets circled the sun vs the common belief that the Earth was the center of the universe.

Mars “the wanderer” Mars is interesting because it looks a lot like Earth. Once thought to have ice caps, rivers, lakes, a viable atmosphere, and even channels (made by intelligent life) War of the Worlds by Wells Book about a Martian invasion, read on the radio, people freaked out. Colonization of mars?

Colonization of Mars? Well the truth is that Mars would be hard to colonize, virtually impossible It is a dead planet Anything thought to be water only exists in small amounts The average temperature ranges from 30 to -140 degrees There is no atmosphere And for the bargain price of $250,000 you can buy a ticket on the Virgin Mobile space shuttle to Mars……..oh yeah it’s a one way flight