Sky Sights for Middle School: July-Sept. 2012

1. About this presentation…. • Is free to be used by students, teachers & public. Please acknowledge it is from FSU. It can also be copied and downloaded. • Is written in Microsoft Power Point that can be read by a number of computer systems. • If you find any needed changes, please contact Dr. Doyle at rdoyle@frostburg.edu

2. Frostburg State Planetarium presents July-Sept. 2012 Sky Sights for Middle School & Intermediates by Dr. Bob Doyle Next Edition: October 2012

3. Big Topics Treated • Horizon, Finding directions, Sunrise/Sunset • How Day Sky Works, Twilight AM & PM • Moon basics, It’s Origin Why has varying shapes? • Bright points seen at night? Easy Summer Planets • Best Stars & Groups Seen on Summer Evenings • 3 Built in Mini Quizzes with answers supplied • Summer ‘12 Moon Schedule & Star tables • Fall ’12 Presentation Schedule & related info

4. Horizon & Directions • When looking at sky, we may view ½ of universe! • Horizon surrounds us, the sky/ground boundary • At top of sky is zenith, 90 degrees from horizon • From North to right, East, then South and West. • Sun rises in East, face sunrise, left is North • Midday shadow N (1pm July – Sept.) • Sun sets nearly in West, face sunset, right is North • Can use Big Dipper’s pointers to find N. Star

5. Sunrise & Sunsets? • Earth’s daily rotation makes it look as if sun rises each morning & sets each afternoon • Time of sunrise, sunset varies thru year • Earliest sunrise & latest sunset in late June • Latest sunrise & earliest sunset in late Dec. • Longest days when sun highest, farthest N • Shortest days when sun lowest, farthest S • Change in sunrise/sunset reduced closer to equator • Change in sunrise/sunset increased near poles

6. Let’s review these ideas • What point in sky is farthest from horizon? • Is it Celestial Pole? Zenith? Nadir? • Which direction recipe WON’T work? • S. Side of tree with moss? Shadow in mid day? • Place where biggest changes with seasons? • Polar Regions? Mid Latitudes? Equator? • Write down your answers for these questions. • Answers: Zenith, Mid day shadow, Polar regions

7. Interesting facts about day sky • Noon sun million x brighter than full moon • Day Sky max. polarization 90 deg. from sun • Maximum sunlight energy in early summer • Sun peaks around 1 pm July - September • Maximum sunlight energy in late June • To find North, face where sun goes down and extend your right arm out, points North.

8. Twilight or Dusk? • When sun disappears from our view, the air overhead is still ‘seeing’ sun and glowing. • When sun 6 dg. below horizon, turn on lights • When sun 18 dg. below horizon, sky darkest • To see faint star groups, sun must be 12 dg. below • Arctic Circle cities have no darkness in June • Equatorial places have shortest twilights • Our twilights last about 90 min. at dusk & dawn

9. What about Moon? • Our moon is 2160 miles across, ¼ Earth’s width • Moon ¼ as big as Earth; if Earth a regular globe (1 ft.wide), moon is a tennis ball. • Earth-moon distance about 30 x Earth’s width. • As Earth, Moon lit by sun with day & night halves • As Moon orbits Earth, see varying part of day side • After line up with sun, moon waxes (grows) 14 d • After full moon, moon wanes (shrinks) 14 days • Moon phase cycle 29.5 dy, approx. month length

10. Just a little bit more about Moon • Moon rocks reveal moon matter from Earth! • Moon due to planets colliding, debris hurled • Moon formed from ring of orbiting debris • Early moon closer, much stronger tides • Moon slowly spiraling out, lengthen our day • Earth has 1st natural moon from sun, 6th largest moon in solar system

11. Another review of ideas.. • As you face sunset, what points North? • Back of Head? Right arm (out)? Left ear? • If Earth 1 ft. wide, how far away is moon? • Is it 10 feet? 30 feet? 100 feet? 300 feet? • How long does moon ‘grow’ or ‘shrink’? • Is it A week? A half month? A month? • Write down your answers to above 3 questions. • Answers: Right arm (out), 30 feet, A half month

12. Bright points we see at night? • Even the nearest planets appear as * (points) as we see them with our eyes; for even these objects far away Venus at closest 100x farther than our moon • To tell a planet from a star, all night stars twinkle and planets usually shine steady. • Also satellites (especially Space Station) shine steadily as creep eastward across sky • Night stars are distant suns, really, really far away compared to our planet neighbors. • If Earth penny size, moon 22” away, sun 730 ft. away (6.3 ft. wide), nearest star is 37,000 mi.away

13. July-September 2012 Planets • Mars & Saturn low in SW in early summer • Mars passes underneath Saturn in mid-August • Crescent moon near 2 planets after mid month • Venus and Jupiter seen in sky before dawn • Crescent moon near Venus in mid month • Mercury seen low in East before sunrise late Aug. • In Sept., Jupiter creeps into late evening in East • Saturn disappears in western dusk in September

14. Summer Even. Stars & Groups • Evening: Big Dipper in NNW with handle on top • Two lowest scoop * point rightward to North Star • Dipper’s handle arcs to golden star Arcturus • High is bright white-blue star Vega • Vega is the brightest star in Summer Triangle • On moonless nights, Milky Way near Triangle • Low in S: Scorpion (‘J’) & Sagittarius (Tea pot)

15. Big Dipper & N. Star, Sum.Even. North Star Pointers

16. Big Dipper’s handle arcs to golden * Arcturus Arcturus

17. Summer Triangle on Summer Evenings Vega Vega Vega Facing E, early summer Facing S, Mid summer Facing W, Late summer

18. Sagittarius & Scorpion low in South on summer evenings See “Tea Pot” and letter “J”

19. Let’s review once more… • What two evening planets this summer? • Are they (Venus, Jupiter) or (Saturn, Mars) • Name two very bright evening summer stars. • Are they (Arcturus, Vega) or (North Star, Orion) • Special sight seen on moonless summer evenings? • Is is (Northern Lights) or (Milky Way)? • Write down your answers, Correct answers are (Saturn, Mars), (Arcturus, Vega) (Milky Way)

20. Summer’12 Moon Schedule • Early July: 7/3 Full moon near Tea Pot • Mid July – crescent moon in morning sky • Late July – evening moon grows to half full • Two Full moons in August: On 1st and 31st • 2nd full moon in a month is called a ‘Blue Moon’ • 2nd week of Sept., the moon is in the morning sky • On Sept.17, crescent moon seen low in W. dusk • Sept. full moon on 29th is Harvest Moon, gives extra evening moonlight thru Oct. 2nd

21. Presentation Schedule & Services • Sunday Presentations at 4 pm • In Compton 224, off lobby & pendulum • Presentation start 9/9: “American Mammals” • Oct. Sunday Pres.: “African Mammals” • Nov. Sunday: “Mammals of Asia” • No Nov. 25 programs (follows Thanksgiving) • Following Presentations, tour Science Center • Call (301) 687-7799 for spoken road directions

22. Frequently asked questions • What are shooting or falling stars? • Pea sized space grit impacting upper atmosphere and bursting into flame. • What if planets aligned (as beads on string)? • They can’t as orbits are not in 1 plane. But even if they could, their pull very weak next to our moon. • Why study other worlds? won’t ease our problems • By understanding other worlds, better know Earth • Your questions are welcome at our public programs.

23. Send any questions to…. • Bob Doyle email rdoyle@frostburg.edu • Be sure that questions involve basics about sky, moon, planets, stars and Museum animals • For questions about 2012, Pluto, Asteroids, Comets – talk to Dr. Doyle • Sunday programs are free on Sundays at 4 p.m. start Sept.9, change monthly at FSU To arrange program for special group, club, call below number and state your date and hour. • Call (301) 687-7799 to request free bookmark, schedule sent to you through mail