Chapter 1 (lecture #1)
Light Year & Astronomical Unit (AU) are distances (pgs 4 & 5) know relative sizes of things: moon, planet, star, solar system, local group of stars, spiral arm,
Milkyway/galaxy, clusters of galaxies, super clusters, filaments and voids
(pgs 5 & 6)
Chapter 2 (lectures #2 & 3)
Constellations -stars of a constellation may be at very different distances
Ancient times constellations loose grouping of stars based on mythology
Now constellations are well-defined regions on the sky. (pgs 12-13)
Celestial Sphere – NCP, Equator, Altitude = to latitude (pgs 17-18)
Ecliptic – remember Sun moves 1o per day and highest motion +23.5o above or -lowest, 23.5o below
Magnitude – bigger number is fainter, (pgs 15-16)
Factor of 2.512 for each mag, (unaided eye limit ~6)
Seasons – tilt of Earth’s axis (pgs 22-25)
Solar day is longer than the Sidereal day (handout 1)
Chapter 3 Moon and its Cycles (Lectures #5, 6, 7)
Phase of Moon know Full/New/1st/3rd
Waxing phases – evening; Waning phases – morning
(pgs 33-35)
Synodic Period - cycle of phases viewed from Earth, 29.5 days
Sidereal Period – 1 orbital period around the Earth (wrt Stars), 27.3 days
Exam 1
Astronomy 152
Chapter 3 (cont’d)
Tidally Locked – we only ever see 1 ‘face’ (Lecture 6)
Eclipses: (pgs 36-41) zone of partial shadow - Penumbra zone of full shadow - Umbra.
Sun & Moon both have angular diameter ≈ 0.5o
Understand angular size (linear diameter/distance)
Lunar Eclipse - only at Full Moon, can last upto 6 hrs, totality upto 100 min
Solar Eclipse, only at New Moon, totality max ~7.5 min
Understand what causes an annular eclipse
Sun’s Atmosphere: corona, chromosphere, photosphere
Nodes, Line of Nodes
Saros Cycle – 18yr 11.33days, but 54+ years or 3 Saros Cycles to return to same place on Earth (Lecture 5; pg 47-48)
Chapter 4 Geocentric/Heliocentric Cosmologies (lecture #8,9 & 10)
Geocentric – Earth is center of Universe