Download Lecture 4 - Empyrean Quest Publishers

Survey
yes no Was this document useful for you?
   Thank you for your participation!

* Your assessment is very important for improving the work of artificial intelligence, which forms the content of this project

Document related concepts

Standard solar model wikipedia, lookup

Astronomical spectroscopy wikipedia, lookup

Transcript
Today!
From Earth’s Perspective:
Celestial Motion:
Stellar Motion
Solar Motion
Planetary Motion
Some stars and constellations
Are circumpolar—never rise or set.
Constellation vs Asterism!
A constellation is one of
88 listed ‘states’ or regions
in the sky: like Orion.
An asterism is not on the list
Of 88, but forms a shape
In the sky: like the Big Dipper,
Part of the constellation Ursa
Major.
Finding Planets:
Once you find the North Star,
Turn around 180 degrees—
The Ecliptic and the planets
will be in the sky toward the South.
The stars (at a given time of night) shift 1 degree a day
Because the earth is orbiting the sun.
Thus the sidereal day is 23 hours and 56 minutes:
It is the time for a star to return to the same place
In the sky.
Solar motion:
Mean solar day--24 hours by definition.
Return of sun to same angle of view relative to the horizon.
seasons caused by tilt of earth’s axis,
solstices--maximum and minimum light,
equinoxes equal light on northern and southern hemisphere.
Planetary motion:
retrograde motion--apparent backtracking of
planets in sky from earth's perspective.
inner planets--Me and Ve
--stay within 'maximum elongation'.
conjunction vs opposition
Mercury 8/30/02
Above Cloud Center
w/ Venus Upper Left