- 1. You will receive a list of unit vocabulary at the top
ofevery unit note packet! How you choose to complete the vocabulary
is up toyou! It should be completed in your science notebook
orstored in your binder and will be checked forcompletion on the
day it is due. [10 points] Expect a vocabulary test approximately 1
week afteryou receive the list.
2. Unit 1The study of stars and space.Big Bang 3. The universe
is expandingo How do we know this? In the late 1920s, Edwin
Hubblediscovered that All galaxies were red-shiftedwhen viewed from
Earth. This meant that all galaxies were movingaway from Earth and
each other, and thus,the universe must be expanding. Learn to
annotate! 4. All matter and energy in the universe was
oncecondensed into a single point 13.8 bya Moments after the Big
Bang, the universe was veryhot and denseo Protons, neutrons, and
electrons formedo Hydrogen formedo There was enough energy to start
nuclear fusion Helium formed 5. Evidenceo Background radiation
Space is...space!o There should be no heat at all (0K)o Scientists
have measured space; 3K (Backgroundradiation exists)o Composition
of matter in the universe 74% hydrogen 24% heliumExpansion of the
Universe 6. A. Electromagnetic Energy1. The sun is the major
energysource for weather changes inthe atmosphere and many of
thechanges occurring at Earthssurface.2. Energy from the sun comes
inmany different wavelengths. 7. Each element orcompound in
itsgaseous formproduce a uniqueset of spectrallines. Spectral lines
act asFINGERPRINTSas they identifyelements present
intheSTARS/GALAXIES.Example: The SUN has thousands of dark lines
&more than 60 elements have been identified bymatching these
lines with those elements known onEarth! 8. The Doppler Effecto The
change in frequency of a wave an observer relative to its motiono
Moving toward you: Waves arecompressed togethero Moving away: Waves
are stretched 9. Redshifto When the light of a distant object
(star,planet, etc.) is viewed through a prism,the spectrum is not
continuouso Black lines appear: Absorption lines Determine which
elements are presento When the object is moving away fromus, the
absorption lines are shiftedtoward the red end of the
spectrum(stretched): Redshift! 10. Using the spectroscope,
astronomers can determinewhether a particular object is moving
toward Earth oraway from Earth 11. Our sun is just one of billions
of stars in the MilkyWay galaxy. Only star whose surface we can
study. Through spectroscopic analysis of the sun, scientistsknow
that most of the known elements are found inthe suno Hydrogen makes
up 74%of the suns masso Helium makes up 24% 12. Sunspots: Dark
areason the suno Cool areaso The magnetic fieldbreaks through
thesurface, causing adisruption in heattransfero The number
ofsunspots varies every11 years. This is knownas the solar cycle.
13. The coreo Nuclear fusion 14. Life Cycles of Stars 15. A Star is
Born 16. A stars life cycle can last billions of years. The
following slides describe the general phases instellar evolution
17. Nebula Dark, cool clouds ofinterstellar gas anddust. Often
referred to asstellar nurseries. Stars begin to formas gas and
dustcollide. 18. Protostar Developing star Not yet hot enoughfor
fusion reactions(10x106 K)http://seethaler.net/space/protostar.jpeg
19. Main Sequence Star Hydrogen to Heliumfusion has begun! The
hotter, largerstars burn H2fastest. This stage makesup 90% of a
starslife.http://content4.bestthinking.com/s/1/topics/500/images/3e6daf0-40a3-495c-8006-5da9e7e9b069_972.jpeg
20. Earths Place in the Universe 21. UniverseOur Milky WayGalaxy is
one ofbillions of galaxies inan expandinguniverse 22. Milky Way
Galaxy Our Sun/solarsystem is one ofan estimated180 billion
starsmaking up thisspiral galaxy 23. Our Solar SystemEarth a small
dense rocky planet, one of 8 planetsthat orbit the sunAND the only
one we know of that has LIFE aswe know it 24. So. What Keeps Us
Going?Newtons Laws of GravityGravity and Inertia 25. Newtons Law of
InertiaStates that a body in forward motion will continue in
forwardmotion unless acted on by an outside
force.InertiaGravityStable Orbit 26. Inertia causes aplanet to move
in astraight line. Gravity pulls aplanet toward thesun. 27.
Rotation The spinning of acelestial body (Earth)on an imaginary
axis 28. RotationA. Earths Direction of Rotation:WEST to EAST2.
Angular Rate of Rotation:THINK one complete rotation360 degrees24
hoursRate = 3600/24 hours = 150/hour 29. B. Effects of Earths
Rotation1. Day and Night 30. B. Effects of Earths Rotation2.
Apparent daily motionof the suna. Earth rotates fromWEST to EASTb.
Sun appears to move inan arc from EAST toWEST 31. Earth is NOT a
perfect sphere.It is an oblate spheroid slightly wider across
theequator (due to its rotationalspin)Earths axis is not stable.
Itmoves/wobbles (like a top).This is known as precession.Its very
slow - 26,000 years tocomplete one cycle.Within the precession
areadditional motions known asnutations. These aresmaller motions
back and forthas the precession occurs. 32. V. Revolution The
orbiting of one celestial body around anothercelestial body.A.
Earths Angular Rate of Revolution1. 360 degrees2. 365 days3. Rate =
3600/365 days ~ = 10/day 33. B. Effects of EarthsRevolution1.
Nighttime constellationschange in a yearly cycle.2. Constellation
groupsof stars that formpatterns of imaginarythings such as
animals,legendary heroes, andmythological gods 34. 3. Seasons a
yearly cycle 35. 5. Seasons of the YearA. Causes:1. Revolution -
Earth revolves around the sun2. TILT - Earth is tilted/inclined on
axis 23 1/2o3. Parallelism of Axis - Earths axis always points in
thesame direction. 36. B. Earths axis is tilted 23.50 relative to
the planeof its orbit. Draw and labelyour diagramaccording to
thediagram at theright. Be sure toname theequator, theTropic of
Cancerand Capricornand note wherewe live. 37. C. The apparent path
of the sun changes with theseasons and with latitude.N.C. 35.5
degrees North Latitude 38. D. Length of Daylight (duration of
daylight) changes with seasons and with latitude. 39. E. Factors
affecting Insolation1. Shape of the Earth (spherical)2. As
latitudeincreases, theangle ofinsolationdecreases, andthe intensity
ofinsolationdecreases. 40. C. Season of the Yeara. As Earth travels
along its orbital path around the sun,the angle of insolation at a
given latitude changes withthe seasons. This depends on how far a
given latitudeis from the direct rays of the sun. The direct
raysmigrate between the Tropic of Cancer (north) andthe Tropic of
Capricorn (south). 41. 4. Time of Daya. The angle
ofinsolationchanges in thecourse of oneday. Maximumintensity occurs
atNoon. 42. b. Looking South The shadow of a vertical pole
indicates how the angle of insolationchanges during the day. The
higher/greater the angle of insolation,the shorter the shadow, and
the greater the intensity ofinsolation. 43. VI The MoonA.The moon
is a naturalsatellite of Earth. 44. B. Physical Properties of the
Moon1. Sizea. Diameter: 2160milesb. Compared to EarthDiameter of
Moon = 2160 = 1Earth 8000 42. Gravitya. 1/6 the gravity of Earthb.
This is because the Moonhas less mass 45. 2. Atmospherea) The Moon
has No atmosphere,so radiation from sun strongb) Gravity too weak
so gasesescape into space.c) Without an atmosphere radiationfrom
the sun is INTENSE!d) Frozen water may exist at theMoons polar
regions, but nonein liquid form 46. 3. Phases of the Moon -Period
of Revolution = 1 month OR 29.5 daysa. The phases of the moon are
caused by the moonsrevolution around Earth.b. Our Earth view of the
changing illuminated part of themoons surface that faces Earth. 47.
c. Waning moon - the decreasein light (on the left), awayfrom being
a full moon to newmoon, is called a. 48. d. waxing moon - as the
moonincreases towards becominga full moon. 49. 4. Moon Rotationb.
Does that mean themoon doesn'trotate?c. YES it does --onerotation
for eachrevolution aroundEarth! 50. 5. Lunar Eclipsea. An eclipse
of the Moon can only take placeat full moon and only if the Moon
passesthrough some portion of the earthsshadow. The shadow is
actually composedof two (2) cone-shaped components, oneinside the
other. The outer or penumbrashadow is a zone where some portion
ofthe suns rays are blocked. In contrast, theinner or umbra shadow
is a region devoidof all direct sunlight. 51. 6. Solar Eclipsea. A
solar eclipseoccurs when themoon passesdirectly betweenthe Earth
andsun.b. New Moon arethe only timesolar eclipses canoccur. 52. 10.
Tidesa. Tides are the alternaterising and falling of thesea.b. This
is caused by theMoons gravitational pull.c. The rising of tides
isaffected by the position anddistance of moon!d. The period from
high tide tohigh tide is 12 hours and 12minutes.e. Tides are a
CYCLICchange.
