Download Frostburg State Planetarium presents

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 [email protected]
Frostburg State Planetarium
presents
Winter 2015 Sky Sights for
Middle School & Intermediates
by Dr. Bob Doyle
Next Edition: April 2015
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 Winter Planets
Best Stars & Star Groups Seen on Winter Evenings
3 Built in Mini Quizzes with answers supplied
Winter ‘15 Moon Schedule & Star tables
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 (12 Noon Jn & Fb, 1p Mar.)
Sun sets nearly in West, face sunset, right is North
Can use Big Dipper’s pointers to find N. Star
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
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
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 Noon Jan,Feb. 1 pm Mar.
Minimum sunlight energy in late Dec.
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.
• 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
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.
• If 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 days, approx. month long
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
Half full moon shows craters
near its straight edge where
sun there is rising or setting.
Winter 2015 Moon Schedule
•
•
•
•
•
•
•
•
•
Early Jan.: Full 1/5 (lava plains seen)
Mid. Jan. : ½ morning moon 1/13 (craters)
Late Jan. : ½ evening moon 1/26 (craters)
Early Feb.: Full Moon 2/3 (lava plains seen)
Mid. Feb. : ½ morning moon 2/12 (craters)
Late Feb. : ½ evening moon 2/25 (craters)
Early Mar. : Full Moon 3/5 (lava plains)
Mid Mar. : ½ morning moon 3/13 (craters)
Late Mar. : ½ evening moon 3/27 (craters)
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
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
Easy Winter 2015 Planets
•
•
•
•
•
•
•
Jupiter is bright, steady point in evening sky
Moon & Jupiter close 1/7-8, 2/3 & 3/2
Venus striking in southwestern dusk
Crescent moon & Venus close 1/22, 2/20, 3/22
Mercury & Venus close 1/8 to 1/12 in SW dusk
Mercury in SE dawn in late February
Saturn seen low in SE late evening sky late March
Winter Stars & Groups
•
•
•
•
•
•
•
Evening: Big Dipper upright in North Northeast
Top two Dipper * point left to North Star.
Same Dipper * point right to sickle of Leo
Sirius is brightest evening star in South
Orion has 3 star belt that points left to Sirius
Stars in and around Orion make big ‘W’ in South
Bright golden star Capella high in Western sky
Big Dipper & N. Star in Winter
North Star
Big Dipper
Orion & Friends
Procyon
Betelgeuse
Belt
Rigel
Sirius
Aldebaran
Let’s review once more…
•
•
•
•
•
•
•
•
Planet seen most in winter ‘15 evening sky?
Is it
Mars? Jupiter? Saturn?
When planet is brightest in the dusk in Winter?
Is it Venus? Mars? Saturn?
Orion’s belt points left to what star?
North Star Sirius Capella
Write down your answers
Answers: Jupiter, Venus, Sirius
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.
Send any questions to….
• Bob Doyle email [email protected]
• Be sure that questions involve basics about sky,
moon, planets and stars