Scientific Method Vocabulary
Observation-the act of using the five
senses to gather information.
Quantitative- analyzing an object using
an exact measurement (number).
Qualitative- description or
distinguishing characteristic about an
object
Inference/hypothesis- a possible
explanation or solution to a
problem based on observations.
Theory – a well-tested and widely
accepted view that explains certain
observable facts.
• http://vimeo.com/13974273
• http://youtu.be/lhTSfOZUNLo
Vocabulary
Observation-the act of using the
five senses to gather information.
Inference- a possible explanation
or solution to a problem based on
observations.
Spectrum – band of various colors of light.
Most of what is known about stars
comes from spectral studies.
There are 3 kinds of visible
spectra:
Continuous, bright-line and
dark-line.
Continuous – unbroken band of colors
from a source sending out all visible
wavelengths.
Continuous spectra can come from a (hot)
glowing solid, a glowing liquid or a glowing
gas (star).
Bright-line spectrum – also called an
emission spectrum, is a series of
unevenly spaced lines of different
colors and brightness.
Every element has its own unique brightline spectrum, like a fingerprint.
Helium emission spectrum
Hydrogen emission spectrum
Wavelength – the distance between
wavecrests (the top of each wave).
Frequency – the number of
wavelengths in a given distance.
Big Bang- theory that all matter and energy
in the universe was compressed into an
extremely small volume that suddenly
began expanding in all directions billions of
years ago.
Big Bang Briefly
http://vimeo.com/5997902
Doppler Effect – apparent shift in the
wavelength of energy (sound or light)
when emitted by a source moving away
from or toward an observer.
Stationary
Moving
Away
Moving
Toward
Lab 3A - Vocabulary
H-R diagram (Hertzsprung-Russell); graph
showing the temperature and absolute
magnitude of a star.
Luminosity – the brightness of a star compared
to the brightness of the Sun as seen from the
same distance.
Absolute & Apparent Magnitude
• Absolute - the magnitude of a star computed
as if viewed from a distance of 32.6 light-years.
• Apparent – a star’s brightness as it appears
from Earth. The sun APPEARS brighter than
the other stars because it is closer to us!
H-R Diagram
• A chart that
shows the
relationship
between the
luminosity
and
temperature
of stars.
Characteristics of Stars
The temperature of a star is determined by
it’s color. BLUE=HOT ; RED=COOL
The composition of stars is determined by
looking at their emission spectrum.
http://sunshine.chpc.utah.edu/labs/star_life/support/HR_animated.swf
http://sunshine.chpc.utah.edu/labs/star_life/support/HR_static.swf
http://sunshine.chpc.utah.edu/labs/star_life/hr_interactive.html
Main Sequence- the 2nd and longest stage in
the life cycle of a star.
Red Giant–a very large, cool, bright, red
star.(3rd stage)
White Dwarf – small, hot, dim star.
The Life Cycle of Stars
THE SUN
The Sun
Process that generates the sun’s energy:
Nuclear Fusion occurs in the Core of the sun.
Fusion is the nuclei of hydrogen atoms fusing
into helium. This process converts mass into
energy.
Sunspots- cool, dark areas of
gas within the photosphere
that are caused by powerful
magnetic fields.
Solar Flares- a
sudden outward
eruption of
gases.
Prominences are
huge arches of
gas high above
the sun’s
surface.
Auroras (Northern Lights) – magnetic
storms in the sky that produce
spectacular bands of colored light.
Terrestrial Planets – “Earth-like” land/rock
planets; 4 planets closest to the sun they
are solid, smaller in size and more dense
NO LONGER
CONSIDERED
A PLANET
Jovian Planets
- like “Jupiter”, 4 outer planets, made of
mostly gases, large, and low density
• Oblate Spheroid- a slightly
flattened sphere
• Roundness Ratio- Comparing the polar
diameter of a sphere to the equatorial
diameter to determine if the object is
perfectly round.
Zenith -the point on the celestial sphere
vertically above a given position or observer