Download Introduction to Astronomy

Survey
yes no Was this document useful for you?
   Thank you for your participation!

* Your assessment is very important for improving the work of artificial intelligence, which forms the content of this project

Document related concepts

Leibniz Institute for Astrophysics Potsdam wikipedia, lookup

Cosmic microwave background wikipedia, lookup

Big Bang wikipedia, lookup

Flatness problem wikipedia, lookup

Star formation wikipedia, lookup

Astronomical spectroscopy wikipedia, lookup

Chronology of the universe wikipedia, lookup

Transcript
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?
•
•
•
•
•
•
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
•
•
•
•
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
•
•
•
•
•
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
•
•
•
•
•
•
Cameras
Variable Stars
Meteors
Asteroids
Supernova
Spectroscopy
Meteor Showers 2013
Solar (Our Sun) Spectrum
A Few Fun Facts
• Milky Way Galaxy
–
–
–
–
–
–
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
–
–
–
–
–
–
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)