Download Astronomy Mastery Objectives Semester Exam Review Kepler Telescope

Astronomy Mastery Objectives
Semester Exam Review
- The astronomical instrument best suited to a particular task in studying the
Universe is a space-based satellite telescope like the Hubble Telescope,
Kepler Telescope or the soon to be activated Webb Telescope.
- Surface optical telescopes can be affected by the weather and atmosphere
whereas space -based probes have to monitor celestial objects and
excessive solar winds created by solar flares.
Radio land –based telescopes require high altitude locations and basins in
order to preserve the slower radio waves.
- Our Earth travels in an elliptical path around our star, the Sun (#1).
Our Earth’s orbital speed increases at the Perihelion (Jan.) or when we are
closest to the Sun (#2).
Our Earth’s orbital speed decreases at the Aphelion (June) when we are
farthest from the sun (#2).
The Earth is 1 AU from the Sun. Mars is 1.5 AU from the Sun. Therefore
Mars has a longer orbital period than Earth because it is farther from the
Sun (#3).
- Hydrogen is fused to Helium at the Core (Thermonuclear Reaction) where
temperatures can reach over 15,000,000 Celsius.
Energy from the reaction then moves to the Radiation Zone.
From the Radiation Zone, energy rises to the Convection Zone where the
temperature cools and mixes.
Energy leaves the Convection Zone and travels up to the surface of the
Sun, the Photosphere.
From the Photosphere, the energy travels through the Chromosphere and
exits the Corona.
It can take over three hundred years for the Sun’s energy to travel from
the Core to the Photosphere and about 8 minutes to travel from the
Photosphere to your skin. The light you see today was produced many
years ago.
- Sunspots occur on the Sun’s surface. They are darker (umbra) and cooler
than the surrounding surface.
Sunspots often occur in pairs.
A hot, magnetically charged column of gas can form a Prominence or arch
between the paired Sunspots.
The arch can detach from the Sun’s surface as a Solar Flare (Coronal Mass
Ejection/CME) which sends solar wind particles into space.
- Sunspot Cycles occur about every 11 years.
Cycles are measured by observing the year with the fewest number of
Sunspots called the Solar Minimum.
Typically, Sunspot occurrences will increase over the next 5.5 years when
the Solar Maximum is reached.
After the Solar Maximum year, the next 5.5 years will show a decrease in
the number of Sunspots until the Solar Minimum year occurs again.
- Solar Winds interact with the magnetosphere in the Earth’s upper
atmosphere at the poles to produce a colorful light display called an
Aurora.
Our moon lacks a core and outer core to produce a magnetic field at its
poles as well as an atmosphere to protect it from solar wind particles.
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Solar Eclipse occurs during the day and at a New Moon Phase. The Moon
is directly between the Sun and Earth and casts its shadow on the Earth.
A Lunar Eclipse occurs at night and at a Full Moon Phase. The Earth is
directly between the Sun and the Moon and casts its shadow on the Moon.
- The rhythmic increase and decrease in height of tidal waters is a result of
the Earth’s rotation and the gravitational pull of the Moon and the Sun.
Typically, a tidal water area experiences two High Tides and two Low Tides
daily.
As the Earth rotates counter- clockwise, the side facing the Moon will
experience a rise of tidal waters until it reaches High Tide, or when the
Moon’s gravitational pull on the tidal water is greatest. A High tide will
simultaneously occur on the opposite side of the Earth because the Moon is
actually pulling the Earth slightly away from the water on that side. When
opposite sides of the Earth experience High tides, the other two sides will
experience Low Tides.
A Spring Tide occurs during New Moon and Full Moon Phases. The New
Moon Phase has the greatest range of height between High and Low Tides
because the Sun and Moon are aligned together and have a greater
gravitational pull on Tidal waters and Earth. The Spring Tide at the Full
Moon also contributes to higher than normal High Tides.
Neap Tides occur at the 1st and Last Quarter Moon Phases and have the
least range in height between High and Low Tides.
- A star is born when contracting gas and dust from a Nebula become so
hot
that nuclear fusion starts. At some point, the outward flow of
energy produced at the core will balance the inward force of gravity and
the star will become stable and live most of its life as a Main Sequence star.
In later years, when nuclear fusion at the core ceases, the outward flow of
energy will overcome the star’s inward gravitational pull and the star will
leave the Main Sequence and become a Red or Super Red Giant; depending
on its original mass.
- Blue and White stars on the Main sequence are hotter, more luminous
massive. They are located on the Upper Main Sequence of the H-R Diagram.
Yellow stars (Our Sun) are medium mass stars with about 6,000 K surface
temperature and a luminosity of 1. They are located on the middle of the
Main Sequence.
Red Stars are less massive, have cooler surface temperatures and a
luminosity less than 1. They are located on the lower end of the Main
Sequence.
Red Giants and Super Red Giants have cooler surface temperatures and
greater luminosities because they are so big.
White Dwarfs are hotter stars with low luminosities because they are so
small.
- The evolution of a sun is typical for all stars until they leave the Main
Sequence. A larger Mass star on the Main Sequence becomes a Super Red
Giant followed by a Nebula and Supernova followed by a Neutron star and
then Pulsar. A super massive star’s Supernova’s gravitational collapse can
develop into a Black Hole.
A medium mass star like our Sun will evolve into a Red Giant followed by a
Planetary Nebula followed by a White Dwarf and then Black Dwarf star.
- Evidence of the Big Bang Theory began with Edwin Hubble’s discovery that
most galaxies are moving away from one another. Hence, the theory arose
that at some point in time, all of the energy that created those galaxies
emerged from a common starting point; the “Big Bang” or enormous
explosion. It is estimated that this event occurred 13-14 billion years ago.