Mr. Tilcoks Sciece 9 Class

The Sun

raza1992 — Fri, 25 May 2007 06:28:41 +0000

The sun is the closea tstar to the ewarth and is the brightest object un the sky. The energy of the sun comes from nuclear reactor where hydrogyn nuclie fuse to form helium and release energy. The sun has been burning for about 5 billion rears and will continue burning for about 5 billion years. The sun has six layers. The core, the radiative zonewhere the gasses are under high presure, the convective zone where heat is transfered to the suurface. The suns surface or photosphere is made up of boiling gasses and has atemp of 5500 degrees celcius . Outside the photospehre is the chromosphere and outside that is the corona. The corona is very hit with a temperatuire round 1 million degrees celcius.

The Dopler Affect

raza1992 — Fri, 25 May 2007 06:22:03 +0000

If a sound or a light source is moving towards you ,you hear a higher pitched frequency however if its a light beam the frequency would be shifted towards the blue.. If a sound or light source is moving away from you, you hear a lower pitch. If it’s lighter the pitch would be shifted toward the red. This is called red shift.

Our Galaxy

raza1992 — Fri, 25 May 2007 06:18:41 +0000

Our Galaxy is called the milky way. It a barred spiral galaxy. It is 100,00 light years across and 1000 light years up and down. Our galaxy has about 200 billion stars. It also has quite a few arms. We haven’t yet discovered 20% of the galaxy.

The expanding universe

raza1992 — Fri, 25 May 2007 06:13:53 +0000

Astronomers have found that all galaxies are moving away from each other. The farther away the galaxy the faster it is receding from us. By examining the from the galaxies through a telescope it was found that the spectrum of the elements had a shift to lower the frequency also called red shift. This led to the suggestion that the universe started originally as a cataclysmic event called the big bang. In 1967 two scientist at Princeton university provided support for this theory when they detected low level microwave noise coming from all directions in space from the radio telescope.

The Life Cycle of a Star

raza1992 — Fri, 25 May 2007 06:07:11 +0000

All stars begin their lives as nebula’s, huge clods of dust and gas. The gases of these nebula’s are made up of hydrogen and helium. Because of the affect of gravity these particles they clump together until they start to undergo fusion. The life-cycle of a star depends on its mass. Low mass stars may live for 1000billion years. Medium mass stars like out sun may live up to 10 billion years. High mass stars may live up to only a few, billion years. Using measurements from spectroscopes scientists have grouped stars into seven colors called spectroscopes. Type O stars have a blue color and burn with a temperature of 25000-50000 degrees Celsius. Our sun which is a type type g star has a temp of 5000 to 6000 degrees Celsius. The brightness of a star is refer to as apparent magnitude. The apparent magnitude refers to the brightness of a star as it appears to the naked eye. The absolute magnitude refers to the amount of light given off by a star. Eventually the star uses up all its oxygen and starts to cool down and sell up into a red giant leaving a dense white dwarf. Stars that begin as high mass stars may end their lives by swelling up into a red super-giant which may lead to them blowing up to form a supernova. Left behind at the center of the supernova is a Small spinning star called a pulsar.

The Gas Giants

raza1992 — Wed, 16 May 2007 02:43:55 +0000

The planets that are known as the gas giants are Jupiter, Saturn, Uranus and Neptune. All these planets lack a solid surface. The features that we can see are cloud made mostly of hydrogen and helium.

Jupiter- Has diameter that is 11 times the size of the earth. Its mass is greater than all the planets combined. Jupiter has at least 16 moons. Four of these moons were discovered by Gallileo and he named them Io, Europa, Ganymede and Callisto. Jupiter has a giant storm on its surface called the red spot.
Saturn is known mainly for its rings. Saturn has at least 17 moons which were first seen by the voyager space probe. The average density of Saturn is less than water. Saturn also rotates quickly on its axis so its day is only 11 hours.
Uranus is a unique planet because its axis of rotation is nearly the same as its orbit around the sun. Uranus is also know for its rings like Saturn and is approximately 22.8 AU from the sun.

The Terrstrial Planets

raza1992 — Wed, 16 May 2007 02:26:09 +0000

The four terrestrial planets are Mercury, Venus, Earth and Mars. They are mainly composed of rocks and metals.

Mercury- The surface temperatures vary from 400 degrees Celsius in the daytime to -180 degrees in the night. These extreme temperatures occur because Mercury has no atmosphere. The surface if Mercury is very similar to our moon. It is filled with craters and rocks.
Venus- Venus is easy to see because it is the closest planet to the sun. Venus appears as a very bright planet because sunlight reflects off the dense clouds of its atmosphere. The carbon dioxide in the atmosphere acts like the glass of a greenhouse holding in the heat. As a result temperature are considerably higher than expected.
Earth- Is the only planet in the Solar System that supports life.
Mars had a red color. Its surface conditions most closely resemble those of the earth, Scientist have studied Mars by sending many probes such as Viking 1, Viking 2 and mars observer to take pictures andto land on the surface.

The Nearest Stars To the Earth

raza1992 — Fri, 11 May 2007 02:53:11 +0000

Common Name	Scientific Name	Distance (light years)	Apparent Magnitude	Absolute Magnitude	Spectral Type
Sun		-	-26.72	4.8	G2V
Proxima Centauri	V645 Cen	4.2	11.05 (var.)	15.5	M5.5Vc
Rigil Kentaurus	Alpha Cen A	4.3	-0.01	4.4	G2V
	Alpha Cen B	4.3	1.33	5.7	K1V
Barnard’s Star		6.0	9.54	13.2	M3.8V
Wolf 359	CN Leo	7.7	13.53 (var.)	16.7	M5.8Vc
	BD +36 2147	8.2	7.50	10.5	M2.1Vc
Luyten 726-8A	UV Cet A	8.4	12.52 (var.)	15.5	M5.6Vc
Luyten 726-8B	UV Cet B	8.4	13.02 (var.)	16.0	M5.6Vc
Sirius A	Alpha CMa A	8.6	-1.46	1.4	A1Vm
Sirius B	Alpha CMa B	8.6	8.3	11.2	DA
Ross 154		9.4	10.45	13.1	M3.6Vc
Ross 248		10.4	12.29	14.8	M4.9Vc
	Epsilon Eri	10.8	3.73	6.1	K2Vc
Ross 128		10.9	11.10	13.5	M4.1V
	61 Cyg A (V1803 Cyg)	11.1	5.2 (var.)	7.6	K3.5Vc
	61 Cyg B	11.1	6.03	8.4	K4.7Vc
	Epsilon Ind	11.2	4.68	7.0	K3Vc
	BD +43 44 A	11.2	8.08	10.4	M1.3Vc
	BD +43 44 B	11.2	11.06	13.4	M3.8Vc
Luyten 789-6		11.2	12.18	14.5
Procyon A	Alpha CMi A	11.4	0.38	2.6	F5IV-V
Procyon B	Alpha CMi B	11.4	10.7	13.0	DF
	BD +59 1915 A	11.6	8.90	11.2	M3.0V
	BD +59 1915 B	11.6	9.69	11.9	M3.5V
	CoD -36 15693	11.7	7.35	9.6	M1.3Vc

The Asteroid Belt

raza1992 — Fri, 11 May 2007 02:51:36 +0000

The asteroid belt is a section of our very vast solar system. The asteroid belt is located somewhere in between planet Mars and Jupiter. Asteroids are little or big pieces of rock that orbit the sun. It is believed that these rocks were suppose to form a planet when this world was first created, however the gravity pull of Jupiter prevented that from happening. Sometimes what happens is that because of Jupiter’s very strong gravity pull some of the asteroids collide causing the two separate rocks to go in different directions. Some of these collisions can cause an asteroid to come hurdling towards Earth.

The main asteroid belt (shown in white) between the orbits of Mars and Jupiter.

The Planets

raza1992 — Fri, 11 May 2007 02:33:29 +0000

The closer to the sun the planets are the more faster they travel around. For example Mercury, which is the closest planet to the sun, takes only 88 days to orbit it, however a planet like Pluto, which is the furthest away from the sun, would take as much as 200 years to orbit it.

Basically you can categorize the planets in two groups. These groups are the Inner Planets and the Outer Planets.
The Inner Planets consist of Mercury,Venus(which are very hot),Earth and Mars(which is very very cold).
The Outer Planets consist of Jupiter, Saturn, Uranus and Neptune. These four planets are Gas giants. They are called this because(you guessed it!) they are made up of gases and nothing else.
One thing that Mr. T was trying to make us understand was that the solar system is BIG.

Pluto is 4.4 billion Km from the sun. And light travels fron the sun at 3000,000 km/sec. So divide the two together 4.4000000000/ 3ooooo= 40 minutes. WOW !

Obove is a pic of the inner planets and the astroid belt all orbiting the sun.