Download Observational Astronomy

Observational Astronomy
Astro-25
Professor Meyer-Canales
Saddleback College
Astronomy Courses Offered
at Saddleback College
• Astronomy 20 - General Astronomy
– Survey/Lecture course
• Astronomy 21 - Solar System
– Geology of the solar system
• Astronomy 25 - Observational Astronomy
– Laboratory course in observational astronomy
Observational Astronomy
The Course
• Study methods used to gather data on
Astronomical objects.
– Perform simple labs
– Discuss advanced observational methods
– Maybe some Astrophotography
• Learn to write up Labs use the scientific method
Observational Astronomy Sites
Emphasis is on Observing Objects
• Science/Math Roof Observations
(16 inch & 8 inch with GPS)
• Santa Ana Planetarium
• Sun Lab
saddleback
• Anza Borrego
Light pollution
Field Trip to Anza Borrego
Light Pollution
An Observational Astronomer’s Enemy
back
Equipment Available for Student Use
Schmidt-Cassegrain telescope
2X 16” Newtonian Telescopes
10X 8” SCT telescopes
Solar Observatory
• Live images can be
displayed
• 16” computercontrolled telescope
• Used in Astronomy
Classes
• Planets and Moon
Observational Astronomy
Schedule
• 7-9 p.m.
– Lecture Professor Meyer-Canales
• 9-11 p.m.
– Lab Instructor Greg Dickinson
• Schedule is weather-dependent
• We do not always follow the schedule
• Field Trips ~16.6 hours:
– Anza Borrego field trip or
– Sun Lab
– Planetarium Santa Ana
Lab Formats
• Formal write-ups (must be typed, see website for instructions)
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Purpose
Theory
Procedure
Data
Analysis
Conclusion
• Not all labs require write-ups
– Worksheets or exercise
Too Much to Comprehend!
Hubble Telescope orbits Earth every ~97 minutes at altitude of
353 miles
Skywalker
or
http://www.aip.de/groups/galaxies/sw/udf/i
ndex.php
An Overview of the Universe
The Scale of the Cosmos
The numbers in astronomy are so large, and small,
that astronomers use scientific notation.
100 = 1
101 = 10
102 = 100
103 = 1000
5.3 x 103 = 5,300
104 = 10,000
8.9 x 104 = 89,000
and, for small numbers
10-1 = 0.1
10-2 = 0.01
2.1 x 10-2 = 0.021
10-3 = 0.001
6.6 x 10-3 = 0.0066
Astronomical distances and sizes are very very very
very large. So, astronomers use different units.
One “Astronomical Unit” (AU)
average distance between Sun and Earth
• 93,000,000 miles
• 150,000,000 km
• 1.5 x 108 km
Distance Light Travels in One
Year is a “Light-year” (LY)
•9.46 x 1012 km
•63,000 AU or 6.3x 104 AU
•0.307 parsecs (pc)
http://micro.magnet.fsu.edu
/primer/java/scienceopticsu
/powersof10/
The Earth
Where are You?
Can you now see your Home?
Earth and Moon System
Our Backyard
240,000 miles (350,000 km)
93 million mi
150 million km
1 AU
Sun size 1
Sun size 2
1 Astronomical Unit = 93 million miles
Pluto
Neptune
Uranus
Saturn
Jupiter
Mars
Earth
Venus
Mercury
Sun
The Solar System
Milky Way Galaxy
Contains Gas, Dust and Stars
us
Sun
4 trillion km
(4.2 light years)
Proxima
Centauri
1 LY = distance light travels in 1 year = 1 trillion km
Milky way
Milky Way Galaxy - Side View
100,000 LY
Face-on view
Milky Way Galaxy - Face-on View
Milky way size
Milky Way Belongs to the Universe
Over 50 Billion Galaxies
Milky Way
2.25 million light years
Andromeda Galaxy
15 billion light years
andromeda
Most distant galaxies = 100 million - 1 billion LY
If our Milky Way Galaxy has ~100 to 400
billion stars in it. How many galaxies are
most likely in the Universe? (multi-verse??)
A) A few hundred thousand
B) Several hundred million
C) Several hundred billion
D) Several hundred trillion
Telescopes gather light
emitted from objects in the
universe
Where are stars born?
What color stars are the hottest?
What are we made of?
Is visible light all that there is?
Like the flavors of Ice
cream – they each
provide us with
different information.
Speed of light =
wavelength x
frequency
λf
c=
Speed of light is
CONSTANT in a
vacuum (space has
many vacuums)!
The Crab Nebula is the remnant of a
supernova explosion that was seen on
Earth in 1054 AD.
It is 6000 light years from Earth. At the
center of the bright nebula is a rapidly
spinning neutron star, or pulsar that
emits pulses of radiation 30 times a
second
Course Overview
• First half - lay the foundation
– Constellations: Find objects
– Telescopes: Tools used by astronomers
– Coordinates: Find unseen objects
• Second half –observe objects
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Moon and solar system
Stars
Unusual stars
Deep sky objects
Cosmology - study of the universe.
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