This presentation …… Can be used by the public, any school, group, provided credit is given to FSU Planetarium. May be downloaded and copied freely. Is written in Microsoft Power Point so many operating systems can view it. Advance by pressing Enter or the Space Bar or Arrows If you see any need for corrections, please contact Dr. Doyle at

Frostburg State Planetarium presents Spring 2015 Sky Sights for Primary Grades & Beginners by Dr. Bob Doyle Next Version: July 2015

Big Topics Treated Horizon, Finding directions, Sunrise/Sunset How Day Sky Works, Twilight AM & PM Moon basics, Made of what? Lady in moon? Bright points at night? Spring 2015 Planets Best Stars & Groups Seen on Spring Evenings 3 Built in Mini Quizzes with answers supplied Spring ‘15 Moon Schedule

Horizon & Directions When looking at sky, we may view ½ of universe ! The Horizon is line between ground and sky. 4 directions along horizon – North, East, South & West. To learn, say Never Eat Salty Worms! North is direction your shadow points in mid day. East is about where sun rises each morning. South is where sun is highest in sky (in mid day) West is about where sun sets in late afternoon.

Why does Sun Rise & Set? For thousands of years, humans believed that sun & sky objects moved about Earth every day! In the 1500’s, Copernicus proposed that the Earth itself was moving, not the sky objects! Copernicus wrote that the Earth was spinning every day and orbiting the sun every year! It took over a century until most were convinced that Copernicus was correct (thanks to Newton). The Earth spins so the sun seems to rise and set.

Let’s review these ideas What is the line between ground & sky? Is it Ground line? Horizon? Edge of sky? In what direction are shadows in mid day? Is it North? East? South? or West? Why does sun seem to rise and set? Because Sun is moving? Earth is spinning? Write down your answers for these questions. Answers are: Horizon, North & Earth is spinning

How Day Sky Works Sun, our day star is so bright that it lights up air, causing it to glow blue on a clear day. As Earth turns, sun seems to rise in morning Due to our turning, sun slowly rolls right. Sun peaks 1 pm through spring months. Sun sets near direction West as we turn. To find North, face where sun goes down and extend your right arm out, points North.

Twilight or Dusk? When sun disappears from our view, the air overhead is still ‘seeing’ sun and glowing. As we turn more away from sun, only very thin, very high air still lit & sky gets darker. This time is twilight or dusk, lasts an hour. During dusk, bright planets, stars show 1 st. By end of dusk, bright star groups seen. Just as dusk after sunset, dawn before sunrise.

What about Moon? Our moon is a ball of rock that orbits Earth. Moon ¼ as big as Earth; if Earth a regular globe (1 ft.wide), moon is a tennis ball. If Earth is regular globe, moon is 30 ft.away As moon orbits us, we see day & night sides In evening, lighted side ‘grows’ for dozen days Then moon is full, shining all thru the night Then moon ‘shrinks’ for 12 days in morning sky Moon’s lighted shapes change as we see its lighted side; its dark side blends in with the night sky

When evening moon looks like a ‘D’, the sun is rising along left edge, lighting up the crater rims and mountains. This ‘D’ moon allows you to see craters & mountains with binoculars held steadily or with a small telescope on tripod (better). A week after the moon is full, you can see it In the morning day sky, as a backwards ‘D’. Even during the morning hours, you can see the craters & mountains on moon with binoculars or a small telescope. Never look at SUN!

Just a little bit more about Moon The moon NOT a big cheese ball! (Sorry!) See figure on moon’s disk from dark plains Dark plains of hard lava, good to land there Over 40 yrs. ago, 1 st men walked on moon Perhaps in 2020’s, humans fly around moon Current rockets can’t carry people to moon, new rockets needed

Spring 2015 Moon Schedule Early April: Full moon 4/4, gradual evening exit Mid April: Evening crescent after 4/19 Late April : ½ full evening moon on 4/25 Early May: Full moon 5/3, gradual evening exit Mid May : Evening crescent after 5/21 Late May: ½ full evening moon on 5/25 Early June: Full moon 6/2, gradual evening exit Mid June: Evening crescent after 6/19 Late June: ½ full evening moon on 6/24

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 dozen days? A month? Write down your answers to above 3 questions. Answers: Right arm (out), 30 feet, Dozen days

Bright steady points at night? Even the nearest planets appear as * (points) as we see them with our eyes; for even these objects very far away (moon=1 unit). Venus 100x farther. 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

Easy Spring 2015 Planets Brilliant Venus dominates the western twilight Crescent Moon & Venus close 4/22, 5/21, 6/20 Bright planet Jupiter in Southwest, Venus to right Moon & Jupiter close on 4/25, 5/23, 6/21 Venus & Jupiter very close on 6/30 in W. dusk Saturn creeps into SE evening sky, closest on 5/22 Mercury below Venus, late April & early May

Best planets to see in Spring 2015 Venus & Jupiter Late June Venus & Jupiter May evenings West Jupiter West at dusk Jupiter Venus

Spring Stars & Groups Evening: Big Dipper upside down, pointers to N.* Same Dipper * point right to sickle of Leo Arc of Dipper’s handle arc to golden “Arcturus” Low in South is Scorpius, it’s stars forming ‘J’ In SE is the Summer Triangle, peaked by * Vega Bright golden star Capella seen low in NW dusk

Big Dipper & N. Star in Spring North Star Big Dipper

South on Spring Evenings 2015 Arcturus Spica Sickle of Leo

Let’s review once more… How to tell a planet from a star? Planet always brighter Planet shines steady Best Evening Planet this April & early May? Venus Jupiter Mercury Mars Which part of Big Dipper points to N.Star? End of Scoop or Arch of Dipper’s Handle Write down your answers Answers: Planet shines steady, Venus, Scoop

Frequently asked questions What are falling stars? (Aka shooting stars) Nearly all are pea sized space grit burning up in our upper atmosphere. Only dust left. Can the planets line up like beads on string? No, orbits are tilted but even if they could, pull is extremely weak, compared to our moon. What keeps stars, planets floating in sky? There’s no up/down in space. Earth floats too!

Send any additional questions to…. Bob Doyle