Download Introduction to Astronomy

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.
(http://www.astronomy.org)
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 wellestablished 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?
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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!!
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
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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 25-30
Stars
How can you learn the sky?
• Astronomy Clubs
– www.hvaastronomy.com
• 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
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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 16-32 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
• http://www.astrosurf.com/avl/UK_index.html
• Planetarium
Cartes du Ciel (Sky Charts)
• http://www.stargazing.net/astropc/index.html
Advanced Observing
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Cameras
Variable Stars
Meteors
Asteroids
Supernova
Spectroscopy
Meteor Showers 2013
Solar (Our Sun) Spectrum
A Few Fun Facts
• Milky Way Galaxy
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Mass: 1012 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
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Large Magellanic Cloud
Small Magellanic Cloud
Leo I
Leo II
M31, M32
M33
163,000 lt. yrs.
196,000 lt. yrs.
750,000 lt. yrs.
750,000 lt. yrs.
2.3 million lt. yrs.
2.4 million lt. yrs.
• Most Distant Object Readily Visible in an Amateur Telescope
– 3C275 2 - 3 billion lt. yrs.
– (quasar) (typically requires 10-in. or larger telescope)