Introduction to Astronomy

What is Astronomy? Astronomy - The science which investigates all the matter-energy in the universe: its distribution, composition, physical states, movements, and evolution. (

Astronomy is a TRUE science Astronomy is based on observations and experiments that can be repeated, and that give the same results no matter who does the experiment or makes the observation. Astronomy makes use of other well- established sciences like physics and chemistry.

Astrology is NOT a science Seeks to discover “hidden knowledge” by the interpretation of omens (like reading tea leaves). Results are not repeatable. Predictions are vague and not testable. Does not incorporate sciences like chemistry and physics.

Astrology predictions for Mrs. White

Why study Astronomy? Natural disasters Recreation and esthetics Scientific inquiry and curiosity Education of an informed society (you !) Our place in the Universe Origin and fate of the Universe (Cosmology) True Science versus science fiction

Natural Disasters: Comet and meteorite impacts, for example. Recreation and Esthetics: The Universe is beautiful!! The Universe is beautiful!! Scientific Inquiry and curiosity: Humankind has always been fascinated by the night sky, astronomy is one of the oldest sciences. Education: NASA outreach programs for students and teachers.

Our place in the Universe: Where is the Earth with respect to the other planets in the solar system, Milky Way galaxy and the ENTIRE universe? Origin and fate of the universe: This part of Astronomy is called Cosmology. Cosmology seeks a scientific explanation for how the Universe began and how it might end (or will it go on forever?).

True Science versus Science Fiction: Some astronomy stuff may be weird, BUT IT’S TRUE.  Black Holes.  Radiation from the beginning of the Universe. Science fiction is just weird.  Favorite movies.  Star Wars  Star Trek  Avatar

Beginnings Learning the Sky Observing Tools What you will see Advanced observing

Learn the Sky 88 Constellations –Only about half visible in the Northern Hemisphere Bright stars –About Stars

How can you learn the sky? Astronomy Clubs – Books Star charts –Planispheres Software Phone Apps

Observing Tools - 1 Eyes –Young eyes ~0.3”-0.4” telescopes –Older Eyes ~0.25”-0.3” What if you wear glasses?

Observing Tools - 2 Binoculars –What to know about Roof Prisms Porro Prisms Coated/Uncoated BAK4, BAK7 Magnification

Observing Tools - 3 Telescopes –Refracting –Reflecting –Catadioptric

What will you see? Eyes - ~0.25” Telescopes –Stars to about magnitude 6-7 –A few non stellar objects Andromeda Galaxy Planets and the Moon A few star clusters and nebula But you want more!

What will you see - 2 Binoculars - ~2”-4” Telescopes –Same stuff as with naked eyes, but….. –You’ll be able to see objects times more faint! –Galaxys, Globluar clusters, nebula, etc.

What will you see - 3 Telescopes - ~4”-20+” –Same stuff as with eyes and Binoculars, but…. –Now you will be able to see objects up to 100’s of times more faint –Ability to see fine detail (resolution)

Galaxies

Planets

Nebulae

Comets

Free Software Virtual Moon Planetarium Cartes du Ciel (Sky Charts)

Cameras Variable Stars Meteors Asteroids Supernova Spectroscopy Advanced Observing

Meteor Showers 2013

Solar (Our Sun) Spectrum

A Few Fun Facts Milky Way Galaxy –Mass: solar masses –Center: Direction: α = 17.8h, δ = -29° (Sagittarius) –Distance: 29,000 lt. yrs. –Diameter: 326,000 lt. yrs. –Velocity: 370 miles/sec relative to 3°K background radiation –toward α = 10h, δ = -20° (southeast Hydra) Some Close Galaxies of the Local Group –Large Magellanic Cloud 163,000 lt. yrs. –Small Magellanic Cloud 196,000 lt. yrs. –Leo I 750,000 lt. yrs. –Leo II 750,000 lt. yrs. –M31, M million lt. yrs. –M million lt. yrs. Most Distant Object Readily Visible in an Amateur Telescope –3C billion lt. yrs. –(quasar) (typically requires 10-in. or larger telescope)