Slides in this set
Ever 24 hours, the sun appears to travel across the sky
The moon appears to be slightly slower than the sun by 49 minuets
Stars appear in set patterns across the sky. These are called constellations.
What can we see in the sky?…read more
The reason why the moon appears to be a half-moon, quarter-moon or full moon is
because it illuminated in a certain way by the sun. The phases of the moon changes
as it orbits the Earth.
When the Moon is on the opposite side of When the moon is
the earth, it is completely illuminated by directed towards sun we
the sun causing us to see a full-moon. see what we call a new-
A sidereal day is when we choose to set our clocks to the amount of time it
takes a star takes to travel across the sky.
Sidereal Day vs. Solar Day
A sidereal day would last 23 hours 56
minuets whereas a solar day would
last 24 hours. Through a course of a
day, it only takes the Earth 23 hours
56 minuets to complete a full 360
degrees. However, the Sun has not
made it's full 360 turn and therefore
needs an extra few minuets (4
minuets to be exact) to reach the
same position in the sky as it did in
the beginning of the day.…read more
How do planets move?
Planets usually move in an east to west direction according to the position of
the sun and moon. However, occasionally, planets seem to slow down and
then go into reverse. This is known as retrograde motion.…read more
How do planets move? (continued)
Retrograde motion can be explained in terms of rotation of the Earth and the
orbits of the Earth, moon and planets.
The moon orbits the Earth and so
therefore is directly in front and
there is no retrograde motion.
The Earth orbits the Sun along with
another seven planets in our solar
system, the milky way.…read more
Stars in the Night Sky
In order to locate stars within the sky we must first find two angles which will
help give the position of the star.
Two angles describe the position star. The
equatorial coordinate system uses a
reference point in the sky which is called
the vernal point.
To find the position of stars we must use
two angles right ascension and left
Right ascension is the measurement from
vernal point from the East. This angle is
measured in time rather than meters,
kilometers etc.…read more