The Sun and Beyond…

The SunDo Now: Write down five things you

know about the sun in your notes…

Our Closest Star: The SunGives off energy in the form of

electromagnetic waves (see esrt p15)

Luminous

Can be classified according to the Hertzsprung-Russel Diagram (our sun is a typical star)

Energy produced by the nuclear fusion of 2 hydrogen atoms to helium

Takes 27 days to rotate

SunspotsSunspots were

first observed by Galileo

Cooler areas on the surface of the sun

Occur in a cyclic manner-every 11 years reach a maxima or a minima

Our Solar System8 planets (see esrt

p15)

Meteors

Asteroid Belt (Mars and Jupiter

Kuiper Belt (Pluto is the king)

Inner (rocky)

Outer (gas giants)

After Neptune is…The Kuiper Belt

The Kuiper Belt, and Oort Cloud

Moving out of our Solar System

The Milky Way- our home galaxy

Milky Way Local Group-The Milky Way is not an island universe, but a member of a small cluster of galaxies called the Local Group. The Local Group contains about 3 dozen known galaxies, clumped in two subgroups around two massive spiral galaxies --the Milky Way, and the Andromeda Galaxy. In several billion years it is possible that the Milky Way and Andromeda will collide and merge to form one huge elliptical galaxy.(Credit: NASA/CXC/M.Weiss)

The MILKY WAYMilky Way Galaxy:

Face-on ViewSchematic, face on illustration of the Milky Way galaxy, showing the prominent spiral arms, the central galactic bulge and the location of the Sun. (labeled & unlabeled) (Credit: NASA/CXC/M.Weiss)

About the Milky Way GalaxyConsists of billions of stars clustered together

Spiral shaped

100,000 light yearts across

Mapped by radiotelescopes –x-ray telescopes (Chandra)

Rotates

Virgo Cluster- our local group

Andromeda is the nearest galaxy to us

Distance in space…Light years-distance light travels in one

year

10 trillion km

Our universe is 25 bilion light years in diameter and 13-15 billion years old

closest star to us is Proxima Centauri- 4.22 light years away

The Big Bang TheoryProposed by George LeMaitre (a roman

catholic priest) 1927

Says universe began from a primordial hot and dense state which exploded material out into space

Is still expanding outward today

Is the Universe Expanding?Yes

Evidence for expansion was first provided by Edwin Hubble- red shift (1929)

And Background (cosmic microwaves)Radiation from space (1964)

universe-review.ca/ I02-08-redshift.gif

Doppler Effect: The apparent change in the wavelength of radiation or sound in which there is a relative motion between the source and the receiver

LightSpectra

Red shift- awayBlue shift- towards

So many questions…Science tries to answer them all

What is the fate of our universe? Will it continue to expand or undergo the Big Crunch?

There are many models to that try to explain this

???????

Wrap up?

use the following to determine....

Universe

Solar system

Milky way

Virgo cluster

USA

NY

Rm 227

What is our Cosmic Address?