REVIEW OBSERVING THE SKY MAJOR TOPICS PPEARANCE

Phys 102 AstronomyREVIEW: OBSERVINGMAJOR TOPICS : APPEARANCEANDTHESKYMOTIONS IN THE SKY- Constellations- Coordinate Systems (horizon, RA & Dec, etc.)- Daily motion- Annual motion of the Sun & Stars (the Ecliptic & Analemma)- Motion and phases of the moon- Motion and positions of the PlanetsI. THE CELESTIAL SPHEREA. Constellations: FIELD GUIDE (FG) Ch. 4 Origin and organization, asterisms Constellation names, abbreviations, genitives(FG pp. 512-513), boundaries (on Atlas Charts) Star names (“other” and Bayer designation)Know how to find them! (Atlas Charts andStar Distances & Magnitudes Worksheets)B. Coordinate systems: FIELD GUIDE Ch. 15Fall 2020Bring YourField Guide tothe exam!!!Review the PowerpointsSky Stuff to Know:Constellations: UMa, UMi, Dra, Boö , CrB,Her, Lyr, Cyg, & AqlMotions: Earth, Sun, MoonSolstices & EquinoxesKnow their definitions!Know their α, δ, PL, date, & constellationKnow how to find the Atlas Chart of Each horizon – horizon, zenith, nadir, meridian, etc. celestial – RA, Dec, NCP, SCP, Celestial Equator(Celestial Coordinates & Changes in Latitude Worksheets)Review All the Worksheets(ALL the calculations)

Review: Observing the SkyFall 2020C. Motions in the skyBe able to fill in daily motion CYCLES pp. 1-10,stars, sun, moon, planets, comets, etc. circle NCP once per daythe table on(Rising, Setting & Time in the Sky and Speed of Noon Worksheets)“The Ecliptic”Time zones & Celestial Navigation (Worksheets)worksheet! annual motion CYCLES pp. 20-32equinoxes and solstices: RA, Dec, sub-solar latitude, constellation, date (Ecliptic Worksheet)the Sun’s motion along the ecliptic, and in declination, the Zodiacsidereal and solar day and the Analemma (Day Through the Seasons Worksheet)named latitudes numerical latitude, why they have names, how Earth’s tilt creates them planetary longitude, elongation & planetary configurations(Graphic Timetable and Positions of the Planets Worksheets, Appendix 11) precession (Astronomy & Astrology worksheet) motion and phases of the moon CYCLES pp. 11-19phases, elongations, times of rising, transit, and setting (Moon Worksheet!!)eclipses definitions & why they don’t happen every monthtides causes and consequencesPage 2

Review: Observing the SkyLab Summary Fall 2020Fall 20201. Atlas ChartsFound the Atlas Charts for the Big & Little Dippers using the guide map and read them tolearn about the stars in those asterisms and other objects in those areas of the sky.2. Star Distances and MagnitudesUsed Appendix 2 to look up information about stars in the Summer Triangle and rankedthem in order of distance, apparent magnitude (V) and absolute magnitude (MV). Brighter objectshave lower magnitudes Vega VVega 0.03 is brighter in the sky than Deneb VDeneb 1.25, but Deneb isintrinsically brighter than Vega: MV,Deneb -7.5 MV,Vega 0.6.3. Celestial CoordinatesIdentified stars on celestial globes using their coordinates and identified coordinates onthe atlas chart sky maps.Right Ascension (Celestial Longitude), 0h to 23h59m59s eastward from Declination (Celestial Latitude), 0 to 90 northward & southward from Celestial Equator4. Changes in LatitudeWrote down the altitudes of the celestial pole and celestial equator for various latitudesthen identified them on horizon diagrams. λ latitude of the observer.ALTITUDE OF CELESTIAL POLE LATITUDE OF THE OBSERVER!5. Star TrailsUsing photographs of the trails of rising stars, we determined the (approximate) latitudesfrom which each photograph was taken.Stars rise and set parallel to the C. E. at an angle of 90 - λobserver to the horizonPage 3

Review: Observing the SkyFall 20206. Transit TimesWe looked up the transit times for a variety of stars using p. 13 in the Field Guide in bothstandard (EST) and daylight saving time (EDT). Vega’s transit times through the summer showedthat stars transit 4 minutes earlier every night.7. Rising, Setting and Time in the SkyLooked up star names in Appendix 2 using their right ascension. From their declinations,calculated their rising and setting azimuths, maximum altitudes and times above the horizon.For λ latitude of the observer and δ declination of the star, we determined the azimuths of risingand setting, the altitude of the star at transit (the maximum), and the hours the star will be above thehorizon using the following equations: sin δ Arise cos 1 cos λ degrees( 90 λ ) δdegreesAmax A 360 Arisesetdegrees2cos 1 ( tan λ tan δ ) hours15 t8. Time ZonesWrote down the longitudes of the time zone centers in the western hemisphere, convertedUT to EDT and EST. For cities at different longitudes, calculated the time of solar noon given thelongitude of each city’s time zone center.Earth turns 15 /hour, 1 in 4 minutes, and 15 arcminutes in one minute() 4 minutes early. 1 degree () 4 minutes late. 1 degree an observer east of the TZ center sees events degrees an observer west of the TZ center sees events degrees 9. Celestial NavigationWe determined an observer’s latitude from the altitude of Polaris and longitude from thedifference between the observed and expected transit times of Procyon on a particular day.( 1 degree east of TZ center.4minutes ) an observer who sees events early is minutes () 1 degree west of TZ center. 4 minutes December Solstice an observer who sees events late is minutes 10. Named LatitudesWe determined wrote the geographic significance of thefive named latitudes and shaded the Earth to show the sun’sposition on the solstices and equinoxes.Arctic CircleTropic of CancerEquatorSun directlyover Tropic ofCapricorn11. The EclipticPage 4Tropic of CapricornAntarctic Circle

Review: Observing the SkyFall 2020We looked up the celestial position of the Sun on Sept. 10 in Leo. Used the Atlas Charts todetermine information about the Solstices and Eqinoxes.The Ecliptic is the apparent path of the sun across the sky through the year. It is also the Earth’sorbital plane.THE TABLE YOU FILLED OUT WILL BE ON THE EXAM VERBATIM! KNOW IT!12. The Day Through the SeasonsUsing the Analemma to find solar declinations, we found the azimuths of rising and setting,the maximum altitudes and hours above the horizon for various cities. We also used the Analemmato determine the clock times of solar noon for various dates.For observer at different latitudes (λ) and different declination of the sun (δ), we determined theazimuths of rising and setting, the altitude of the star at transit (the maximum), and the hours of daylightusing the same equations as in lab exercise 7.13. Graphic Timetable: Events of a Single NightAfter aswering questions about the the Sky & TelescopeSkygazer’s Almanac, we used it to find all the events that will occurduring the night of Sep. 29-30, 2019.14. Planets in the skyUsed Appendix 11 to look up planetary longitudes of the sunand (5 naked-eye) planets on a given date. From these we determinedthe Atlas Charts for the positions of the sun and planets to find whatconstellation each was in. We then calculated the elongations andplotted their positions for an observer at sunrise and in the solarsystem.Planetary Longitude measured east from to 360 along ecliptic.Elongation angle from sun to object.15. Astronomy and AstrologyUsed Starry Night to look at the sky atthe moments of our births from the places ofour births. Compared the astronomicalconstellations the sun, moon and planets werein to the astrological “houses” they were inaccording to our natal charts. Most of theconstellations were different showing thatastrology is not a scientific representation ofthe sky.16. Moon PhasesFilled out a table of phases, elongations,rising time, transit time, and setting time forthe eight phases from one piece of giveninformation on each.Page 5

Review: Observing the Sky Fall 2020 . Page 2 . Be able to fill in the table on “The Ecliptic” worksheet! C. Motions in the sky daily motion CYCLES pp. 1-10, stars, sun, moon, planets, comets, etc. circle NCP once per day (Rising, Setting & Time in the Sky and Speed of Noon Worksheets) Time zones