'Advanced Astronomy'
Author: Professor Avon
Table of Contents
.:. Chapter One: The Aurora Borealis
.:. Chapter Two: Black Holes
.:. Chapter Three: Worm Holes
.:. Chapter Four: White Holes
.:. Chapter Five: Lunar Eclipses
.:. Chapter Six: Solar Eclipses
.:. Chapter Seven: Equinox and Solstices
Chapter 5: Lunar Eclipses
Video: http://uk.youtube.com/watch?v=IVkkCVh5t0E
Image: http://www.opencourse.info/astronomy/introduction/04.motion_moon/lunar_eclipse_total.gif
Eclipses are generally something have awed both wizards and muggles for centuries. Many years ago researches began to study these phenomenal events to try and collect as much information about them as they possible could. During their analysis they determined that there wasn’t just one lunar eclipse but three. The Penumbral Lunar Eclipse, the Partial Lunar Eclipse, and the Total Lunar Eclipse.
The first one mentioned, the Penumbral Lunar Eclipse, is by the most subtle event of the three. Most people don’t usually recognize these unless they are trained and are looking for academic purposes only. It’s subtle because the moon passes through the Earth’s penumbral shadow. This penumbral shadow is smaller and usually fainter and clearer than the normal shadow called the umbral shadow. The Partial Lunar Eclipse is one of the events that wizards and muggles look forward to. Mainly because it is better seen by an unaided eye. A Partial Lunar Eclipse occurs when a portion of the moon passes through the Earth’s umbral shadow. Which distinctly hides a portion of the moon. The last eclipse is the Total Lunar Eclipse. This eclipse itself is one of the most amazing events ever to be seen. The entire moon passes through the Earths umbral shadow which allows the moon itself to take on a large range of colors during this phase.
So what’s so exciting about that? Well besides the fact that it looks really really cool it also has some special effects on wizards and the wizarding world. There are a handful of certain plants that can only be used for their magical abilities during this time frame. Some can only be picked and plucked during this time, while others will only grow during this time. There are also spells of sorts that can only be cast correctly during this time frame too. But as this is Astronomy, you will not be learning those spells or plants from this book.
As you can see from the chart listed below, Lunar eclipses happen only a few times a year. With Total Lunar eclipses being the most rare of the three. These eclipses can be widely seen by a lot of people in the world however not everybody will be able to see them due to their location. That is why there are also “viewing locations” listed as well.
February 21, 2008 - Total Lunar Eclipse - The eclipse will be visible throughout most of the Americas, Africa, and Europe
August 16, 2008 - Partial Lunar Eclipse - The eclipse will be visible throughout most of South America, Europe, Africa, Asia, and Australia
February 9, 2009 - Prenumbral Lunar Eclipse - The eclipse will be visible throughout most of eastern Europe, Asia, Australia, the Pacific Ocean, and western North America.
July 7, 2009 - Prenumbral Lunar Eclipse - The eclipse will be visible throughout most of Australia, the Pacific Ocean, and the Americas
August 6, 2009 - Prenumbral Lunar Eclipse - The eclipse will be visible throughout most of the Americas, Europe, Africa, and western Asia
December 31, 2009 - Partial Lunar Eclipse - The eclipse will be visible throughout most of Europe, Africa, Asia, and Australia
Now that you are aware that these events are few and far between I would like to take some time to explain why Muggles feel like they have seen more lunar eclipses than can actually be documented. Of course, my dear Witches and Wizards, it all has to with magic. These silly Muggles will actually make up astronomical events as excuses for what they are seeing. That’s right! They will actually claim to have seen an eclipse when in fact its just some wizards having a good time.
A few years ago such an event happened and Astronomers were absolutely baffled as to how this lunar eclipse suddenly appeared when it was no where near the correct date of their calculations. They wrote it off as pseudo-lunar eclipse but now you will know the real story. A handful of very powerful wizards got together to enjoy each others companies. After while they grew bored of being the house and decided it was best to get some fresh air. It was there they spotted the full moon, glowing back at them like a sign. No one is really quite sure how the conversation came about but eventually they all agreed it was the a fantastic idea to conjure a giant size disk that would cover up the majority of the moon. It took a lot of time and energy but they eventually did get the disk created and levitated it upwards in front of the moon. The moon, being as bright as it was, glowed on the very edges and created a lunar eclipse type sight. The wizards thought it comical, while the astronomers were utterly perplexed.
Chapter 6: Solar Eclipses
Video: http://uk.youtube.com/watch?v=-BmrFY5quq4&feature=related
Image: http://web.mit.edu/kayla/Public/Backgrounds/Solar%20Eclipse.JPG
An eclipse of the Sun occurs when the Moon passes between the Earth and the Sun. The Moon blocks the light of the Sun and a shadow of the Moon is cast on the Earth's surface.
During a solar eclipse, the Moon actually casts two shadows towards Earth. One shadow is called the umbra which becomes smaller as it reaches the Earth. The second shadow is called the penumbra which becomes larger as it reaches the Earth. A total solar eclipse, or a complete blocking out of the Sun's light, can only be seen from the area on the Earth's surface that enters the Moon's umbra, the smaller shadow. People viewing the eclipse from the area of the Earth's surface that enters the penumbra, the larger shadow, will see only a partial blocking of the Sun.
A total solar eclipse, like the eclipse of February 26th, can only occur when two events happen at the same time. The first event is a new Moon. This phase of the Moon occurs when the Sun is almost directly behind the Moon, and we see only a sliver of the Sun's light reflected by the Moon. During this time the Moon and the Sun appear close together. The second event that must occur is that the Moon must be in the right position, directly in the line of sight between the Earth and the Sun. These two events occur at the same time about once every year and a half.
In a solar eclipse, the Moon moves between the earth and the Sun. When this happens, part of the Sun's light is blocked. The sky slowly gets dark as the Moon moves in front of the Sun. When the Moon and Sun are in a perfect line, it is called a total eclipse. These are very rare. Most people only see one in their lifetime.
Chapter 7: Equinox and Solstices
Solstices
At two point through out the year, the tilt of the Earth’s axis reaches its maximum angle compared to the Sun, and begins to move back the other direction. This usually happens around June 21 st, and December 21 st. These days are known as solstices. On these solstices the rays of the Sun shine directly on one of the two tropics. During the June Solstice the rays of the Sun shine directly on the Tropic of Cancer. During the December Solstice the Sun’s rays shine on the Tropic of Capricorn. These special days are special magical days, the druids can use these days to help them grow harvest as they store there magic in a series of orbs.
Equinox
As the Earth moves around its orbit it reaches two points during the year where the tilt of its axis causes it to be straight relative to the Sun. These days are known as equinoxes. During these equinoxes the rays of the Sun shine directly on the equator. This happens on approximately March 20th, and September 22nd. Again, they are brilliant days for followers of wizardological herbology and potion makers, they mark the beginning and the end of the harvest seasons.