Transcript Introduction to Astronomy

Introduction to Astronomy
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
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 none 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
Nebula
Comets
Free Software
• Virtual Moon
• http://www.astrosurf.com/avl/UK_index.html
• Planetarium
– WinStars
• http://site.voila.fr/winstars/english/index2.html
– Cartes du Ciel (Sky Charts)
• http://www.stargazing.net/astropc/index.html
Advanced Observing
•
•
•
•
•
•
Cameras
Variable Stars
Meteors
Asteroids
Supernova
Spectroscopy
Meteor Showers
Meteor Shower Dates
Shower
Best Dates
Maximum Shower
Activity
Approximate Meteors/Hr
RA/Dec:
Notes
Quadrantids
Jan1-6
Jan.3
60
15h 30m +50.0
Medium speed; blue
Corona Australids
Mar 14-18
Mar.16
5
16h 24m -48.0
Lyrids
Apr 19-25
Apr. 22
10
18h 10m +32.0
Swift
Eta Aquarids
May 1-10
May. 6
35
22h 23m -10.0
Very swift persistent train
Ophiuchids
Jun 17-26
Jun. 20
5
17h 23m -20.0
Capricornids
Jul 10-Aug 15
Jul.25
5
21h 03m -15.0
Yellow; very slow
Delta Aquarids
Jul 15-Aug 15
Jul.29
20
22h 39m -17.0
Double radiant; rather
Aug.7
10
23h 07m +02.0
faint meteors
Piscis Australids
Jul 15-Aug 20
Jul.31
5
22h 43m -30.0
Capricornids
Jul 15-Aug 25
Aug. 2
5
20h 39m -10.0
Bright yellow; slow
Aquarids
Jul 15-Aug 25
Aug.6
8
22h 15m -15.0
Double radiant; faint
22h 07m -06.0
meteors
Swift; excellent
Perseids
Jul 23-Aug 20
Aug.12
75
03h 08m +58.0
Giacobinids
Oct 6-10
Oct.8
5
17h 25m +57.0
Orionids
Oct 16-27
Oct.22
25
06h 27m +15.0
Very swift; with trains
Taurids
Oct 20-Nov30
Nov.4
10
03h 47m +14.0
Double radiant; very slow;
03h 47m +22.0
flat maximum
10h 11m +22.0
Very bright: Peak every
Leonids
Nov15-20
Nov.17
10
33 years; exceptional.
Geminids
Dec 7-15
Dec.13
75
07h 31m +32.0
Medium speed; Bright
Ursids
Dec 17-25
Dec.22
5
14h 27m +78.0
Usually weak
Solar (Our Sun) Spectrum
Questions?
• 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)