Transcript Astronomical Phenomena

Solar Wind
Solar Wind and How it Affects Earth
Aurora Borealis
NASA The Mystery of the Aurora
Phases of the Moon

The Moon is a cold, rocky body about 2,160
miles (3,476 km) in diameter. It has no light
of its own but shines by sunlight reflected
from its surface.
 The Moon orbits Earth about once every 29
and a half days.
Phases of the Moon
•
As it circles our planet, the changing
position of the Moon with respect to the
Sun causes our natural satellite to cycle
through a series of phases:
Phases of the Moon
New Moon > New Crescent > First Quarter >
Waxing Gibbous > Full Moon >
Waning Gibbous > Last Quarter > Old
Crescent > New Moon (again)
Phases of the Moon

NASA 2013-moon-phases
New 2013 Phases of the Moon Animation
Eclipses

Eclipses occur when an apparently large
celestial body (planet, moon etc.) moves
between the observer (that's you!) and a
more distant object - the more distant object
being eclipsed by the nearer one.
Solar Eclipses

Solar eclipses occur when our Moon moves
between the Earth and the Sun. This
happens when the inclined orbit of the
Moon causes its path to cross our line of
sight to the Sun. In essence it is the observer
falling under the shadow of the moon.
Solar Eclipses

There are three types of solar
eclipses:

Partial The Moon only covers part of the
Sun's surface.
 Total The Moon completely obscures the
Sun's surface.
 Annular The Moon is at aphelion (furthest
from Earth in its elliptic orbit) and its disc is
too small to completely cover the Sun. In
this case most of the Sun's disc is obscured all except a thin ring around the edge.
Solar Eclipses

Solar Eclipses
Solar Eclipse Schedule
Observing Solar Eclipses
Observing Solar Eclipses Safely
Lunar Eclipses

Lunar eclipses occur when the Earth moves
between the Sun and the Moon, and the
Moon is in the Earth's shadow. They occur
under the same basic conditions as the solar
eclipse but can occur more often because
the Earth's shadow is so much larger than
the Moon's.
Lunar Eclipses
Astronomers recognize three basic types of
lunar eclipses:
1. Penumbral Lunar Eclipse
•The Moon passes through Earth's penumbral
shadow.
•These events are of only academic interest
because they are subtle and hard to observe.
2. Partial Lunar Eclipse
•A portion of the Moon passes through Earth's
umbral shadow.
•These events are easy to see, even with the
unaided eye.
3. Total Lunar Eclipse
•The entire Moon passes through Earth's umbral
shadow.
•These events are quite striking due to the
Moon's vibrant red color during the total phase
(totality).
Lunar Eclipses
NASA | Lunar Eclipse Essentials in 3D
Lunar Eclipses
Lunar Eclipse Schedule
Comets

A comet is a small body in the solar system
that orbits the Sun and (at least occasionally)
exhibits a coma (or atmosphere) and/or a tail.
 Comets whose orbit brings them close to the
Sun more frequently than every 200 years are
considered to be short period comets, the
most famous of which is probably Comet
Halley, named after the British astronomer
Edmund Halley, which has an orbital period
of roughly 76 years.
Tides

Rising and falling of ocean waters as a
result of the Moon’s and Earth’s gravity
 The force of attraction between all masses
in the universe is called gravitational force
 Caused by the difference between the force
of gravity on the side of Earth nearest the
Moon and the force of gravity on the side of
Earth farthest from the moon
Stretching Effect
Bay of Fundy
Comets

Comets have a very eccentric orbit (very
elliptical), and as such spend most of their
time a very long way from the Sun. Comets
are composed of rock, dust and ices. When
they come close to the Sun, the heat
evaporates the ices, causing a gaseous release.
This gas, and loose material which comes
away from the body of the comet is swept
away from the Sun by the Solar wind,
forming the tail.
Comets

Comets whose orbit brings them close to the
Sun more frequently than every 200 years are
considered to be short period comets, the
most famous of which is probably Comet
Halley, named after the British astronomer
Edmund Halley, which has an orbital period
of roughly 76 years.
Asteroids

Asteroids are celestial bodies orbiting the
Sun in more or less regular orbits mostly
between Mars and Jupiter.
 They are generally rocky bodies like the
inner (terrestrial) planets, but of much
smaller size. There are countless in number
ranging in size from about ten meters to
thousands of kilometres
Meteoroids

These objects are small pieces of space
debris left over from the early days of the
solar system that orbit the Sun. They come
in a variety of shapes, sizes an
compositions, ranging from microscopic
dust particles up to about ten meters across.
Meteoroids

Meteoroids is the name given to such
objects when they are floating in space.
 A Meteor is the name given to the visible
atmospheric phenomenon.
 Meteorites is the name given to objects that
penetrate the atmosphere and land on the
surface