Our galaxy North America Solar System Oreo cookie Sun A sprinkle

FYI: A Trillion can be thought of as a million millions! AU (Astronomical Unit) Equal to 150 million km Measures distance within the Solar System Light Year Distance light travels in one year One light year=10 trillion km Measures distance beyond the Solar System FYI: A Trillion can be thought of as a million millions!

Read page 415 to find the answer to the following question: Why does east appear on the left and west appear on the right on the sky map?

Star formations resembling people, animals or objects Divides night sky into 88 regions

Spectra Spectroscope Range of wavelengths a star emits Instrument used to study stars Determines what types of elements are present Spreads light into different wavelengths

Waves Locations Radio New stars Cold, dark regions of space Infrared Star-forming regions Ultraviolet Young stars X-rays/Gamma Rays Exploding stars High energy gas jets

Launch Lab p. 423

Nuclei of several atoms combines into one large nucleus Releases huge amounts of energy Produces stars

Star: Ball of gas Held together by gravity Hot core (nuclear fusion occurs) Energy from stars core radiates into space causing star to shine

Groups of Stars 1. Single stars 2. Binary system Two stars orbit each other 3. Clusters All stars the same age Formed at the same time Are the same distance from earth Open or globular clusters

Classified according to spectra Spectra and color are determined by surface temperature Mass and color are related Organization of stars Hottest Blue-White Most mass   Orange Yellow White Coolest Red Least mass

Main sequence stars Form a line from the upper left to the lower right Mass determines both temperature and luminosity

Non-main sequence stars Top right Cool yet luminous Unusually large Called giants or supergiants

Non-main sequence stars Bottom Hot yet dim Unusually small White dwarfs

Pulled together by gravity ↓ Forms Step 1 Nebula Cloud of gas and dust Pulled together by gravity ↓ Forms Protostar Cores become hot and dense Nuclear fusion begins Thermal energy released *Process takes thousands of years

Step 2 Main Sequence Stars As soon as it begins to fuse into helium ↓ -Hydrogen is nearly gone -Star leaves the main sequence -Becomes a red giant or a supergiant

Step 3 White Dwarf Lower mass stars Hot, dense slowly cooling sphere of carbon Run out of helium Expose cores

Step 4 Supernova An enormous explosion that destroys a star Iron forms in the core Lose energy and collapse Star explodes

Step 5 Neutron Star A dense core of neutrons that remains after a supernova

Planetary Nebulae Cast off hydrogen and helium from white dwarfs Can be used to form new stars Supernova Remnants Cloud of gas and dust from a supernova Can be used to form new planets and stars

Happens after some massive stars collapse An object whose gravity is so great no light can escape Does not suck in matter like a vacuum Cannot be seen Existence inferred from surrounding objects

Huge collections of stars Dark Matter Matter that emits no light at any wavelength Dark Energy A force pushing the galaxies apart Together, they makes up 90% of the universe

The universe began from one point billions of years ago and has been expanding ever since Universe began 13-14 billion years ago Began smaller than a proton

*This happens in 200 seconds=3.3 minutes In less than one second, the universe expanded trillions of times in size Called inflation Universe is filled with soup of particles called quarks Quarks group together in groups of three forming protons and neutrons Protons and neutrons join together to form atomic nuclei *This happens in 200 seconds=3.3 minutes

380,000 years later… Electrons orbit nuclei First atoms created Particle soup thins to allow light to travel through the universe

300 million years later… Gravity pulls together gas and dust to form first stars and galaxies 10 billion years later… Expansion speeds up again because of dark energy

13.8 billion years later (Present Day)… Expansion continues to accelerate

“I do not feel obliged to believe that the same God who endowed us with sense, reason, and intellect has intended us to avoid their use.” ~Galileo “…Science is not a threat to their faith, but rather a great support. That by appreciating God’s creation, we come closer to God.” ~Guy Consolmagno (Vatican astronomer)

“The beginning of the world is not the work of chaos that owes its origin to something else, but it derives directly from a supreme principle that creates out of love. The Big Bang, that today is considered to be the origin of the world, does not contradict the creative intervention of God; on the contrary, it requires it.” ~Pope Francis