Astronomy Final Exam Review

1. Astronomy Final Exam Review The answers

2. Pseudoscience is a study that tries to explain scientific phenomenon. It does not follow the scientific method. An example would be astrology. • Astronomy is the study of objects in space; astrology is the study of myths attached to stars’ locations in relation to Earth, and how this affects your personality.

3. Kepler-3 laws of planetary motion • Copernicus-Heliocentric theory of the universe • Newton-3 laws of motion • Galileo- perfected the telescope • Brahe- greatest naked-eye astronomer of all time • Doppler-Doppler effect named for him; used by Hubble to prove the expansion of the universe • Stonehenge-astronomic calendar in England

4. Objective- main lens-forms a small image • Eye piece- used to magnify image; make it convenient • Finder scope-larger field of view to find object before magnifying it with the full telescope • Focus- brings the image into clear view

5. The primary or main purpose of a telescope is to enlarge objects that are far away. • The most powerful land telescopes are at the tops of mountains in order to decrease the effects of the atmosphere.

7. Reflecting telescope

8. Radio telescopes pick up the invisible portion of the spectrum, whereas optical telescopes pick up the visible portion. • In the future, telescopes will be multi-mirrored, and computer-aided. • A prism is used to break white light into its rainbow of colors. This is used to determine the speed and distance of galaxies.

10. Spectroscopes are used to break white light into colors, allowing astronomers to determine what elements are in a star, how far away objects are, and how fast they are moving. • Violet has the shortest wavelength, red has the longest. • Red shift- the object is moving away; blue shift, the object is moving toward

11. Altitude- height above the horizon • Azimuth- degrees around the sphere, away from north (0) • Zenith-highest point; directly overhead • Nadir- directly beneath you • Horizon- where the sky appears to meet the land

12. A 75---170 • B 45---90 • C 20---345 • D 5---270 • E 45---250 • F 20---45

13. The big band theory states that the universe began in an explosion of matter and energy and has been expanding ever since. • Universe- 13 BY The sun- 4.6 BY • The nebular theory states that the solar system formed from a rotating cloud of gas and dust, which condensed to form the sun and all other solar system objects

14. Elliptical

15. Spiral

16. Barred Spiral

18. Star- celestial object composed of gas, held together by its own gravity, and supported by nuclear fusion in its core • Galaxy- very large collection of gas, dust, and stars orbiting a common center of mass • Nebula- star nursery • Planetary nebula-remnants of a supernova explosion • Supernova- how massive and supermassive stars begin the end of their lives (after red giant or supergiant phase) • Quasar- rare, starlike object that gives off radio waves as material is sucked toward a black hole • Light year- the distance light travels in a year • AU-(astronomical unit)- 1AU= distance from Earth to the sun

19. Polaris- aka The North Star • Sirius- brightest • Alpha (Proxima) Centauri- closest • Betelgeuse- In Orion, largest

20. A star’s color reveals its surface temperature • Stars are 75% Hydrogen and 25% Helium • Apparent magnitude- brightness as seen by human eyes on earth; Absolute magnitude- intrinisic brightness; how bright it would be at 10pc

21. White dwarfs=A • Main sequence=D • Red giants= C • Supergiants=B • Sun will never be=B • Bluish main sequence= E • Red main sequence= F

23. Mercury-no atmosphere • Venus-hottest, spins backward • Earth-only one with life • Mars-red; polar ice caps • Jupiter-largest; 63 moons • Saturn-brightest ring system • Uranus-Green; tilted 90 toward the sun • Neptune-blue; great dark spot • Pluto-no longer a planet

24. We are able to see planets because they are reflecting sunlight. • As you increase the distance from the sun, you increase the orbit time

25. New moon-dawn-sunset-none • 1st quarter-noon-midnight-half (right side) • Full moon-sunset-dawn-full • 3rd quarter-midnight-noon-half (left side)

26. Earthshine

27. Maria-lunar lowland filled by successive flows of dark lava • Highlands-mountains • Craters-circular remnants of impact • Copernicus and Tycho are the names of craters (all craters are named after famous scientists) • Gravity on the moon is 1/6 that of Earth.

29. 1. core • 2. radiative zone • 3. convective zone • 4. photosphere • 5. chromosphere • 6. corona

30. Sunspots-magnetic storms on the sun’s surface. They appear dark because they are cooler than the surrounding surface. • Sunspot cycle is an 11-year cycle of sunspot activity that corresponds with an increase in aurora activity.

31. Lunar eclipse red moon S-E-M 1 hour with every full moon, somewhere on Earth Solar eclipse moon blocking the sun S-M-E 2-11 minutes (totality) with every new moon (not total) somewhere on Earth

32. The orbits of the planets are ellipses with the sun at one focus. • No Need for Bode’s law

33. Satellite-any object that orbits another (manmade vs natural) • Meteor-an object in space that gives off light as it burns in Earth’s atmosphere • Meteorite-the object strikes Earth’s surface • Comets-objects beyond the orbit of Pluto; give off a streak of dust and ice when they get near the sun (tail)

35. A meteor shower happens when Earth passes through the path of a comet, and the pieces of comet burn in Earth’s atmosphere.

36. Gravity is the attraction between two objects that have mass. • Inertia-an object in motion remains in motion… • Rotation-spin on an axis • Revolution-orbit around another object • Perihelion-closest to the sun in orbit • Aphelion-farthest from the sun in orbit

37. Asterism-a named group of stars not identified as a constellation (ie. The Big Dipper and Little Dipper)