1 - Introduction

Welcome to the Astronomy Course. This course is designed to help you build your knowledge of the galaxy that we inhabit. We will cover topics such as types of planets, stars, galactic distances, and galactic anomalies.

The Galaxy offers a wide variety of planets and astronomical phenomena which continue to baffle scientists to this day. Ranging from city-planets like Coruscant to clusters of black holes to binary star systems with inhabitable worlds, the galaxy is very diverse. Once one goes into the unknown regions, the diversity continues to grow.

During this course you will learn some of the basics of starship navigation, as you will learn the different distances, presented to you at a navi-computer, and possible hazards of navigating through the galaxy, such as stars and black holes.

I would also like to remind you that this course is by no means a comprehensive guide, as such I would like to recommend that you research more into these subjects.

2 - The Galaxy

First and foremost, we will briefly cover the galaxy in its entirety. The difference between a galaxy and the universe is a galaxy is a huge gravitationally bound system of stars, interstellar gas and dust, plasma, and unseen dark matter, and they can contain upwards of 1 trillion stars. The universe however is the sum of all known matter that exists.

Galactic distances

Even the smallest galaxies are massive, almost to the point of being beyond imagination. It is only through hyperdrive that we are even able to get from one planet to another. Mere kilometers are simply inefficient when it comes to measuring distances across the galaxy. Astronomers have developed larger units of measurement.

Here is how Astronomers measure the distance between celestial bodies:

• Distance to Satellites: Kilometers
• Distance to Planets: Astronomical Distances
• Distance to nearby Stars: Light years or Parsecs
• Distance on the Galactic Scale: Kilo Parsecs
• Distance to other Galaxies: Mega Parsecs

Astronomical Distances:

Sometimes known as an A.U. (astronomical unit), the current accepted distance for this is 150 Million Kilometers (93 million miles).

• Light-years: This is the distance light travels in one years (365 Coruscanti days) time. This is approx 9.461 petameters. (9,461,000,000,000 km). Light Years are NOT a unit of time.
• Parsec: This stands for parallax of one arc second. 1 parsec is equal to 3.262 light years.
• Kilo Parsec: This is equal to 1 thousand parsecs. (3261 Light-years.)
• Mega Parsec: Is equal to 1 million parsecs. (3,261,564 light years) These are typically used to measure distances between neighboring galaxies.

I would like to clarify here what Han Solo meant when he claims he ran the Kessel Run in less than 12 Parsecs. The standard run is approximately 18 parsecs. Solo was able to make the run in a shorter distance by skirting close to one of the super massive black holes. A black hole warps time and matter the closer you get to it; as such, it shortened the distance needed to get from the beginning to the end of the run. (The actual run was made in 11.5 parsecs)

3 - Planets

Before we talk about individual planets, I should briefly explain what a solar system is. A solar system, often just called a star system, is a collection of planets, satellites, and other heavenly bodies orbiting around a central star (or, in some cases, stars). Not every star has a solar system and the number of planets per solar system will always vary. Planets and smaller objects are drawn by the star's gravitational pull into elliptical paths called orbits.

There are many different types of planets within the galaxy; while I am only going to discuss a few of them, the ones I am going to cover are fairly well known and serve as good case studies of the wide variety of planets we have.

Tatooine

This is a desert planet in the binary star system, Tatoo. This planet once had large oceans and world spanning jungles, but it was glassed over by an orbital bombardment by the Rakata. This fused the silica found in the ground into glass; the sand now covering Tatooine is remnants of this glass that has fragmented in the generations since.

Naboo

This planet is an enigma to astrophysicists. The reason for this is the porous, plasma interior and lack of a molten core that cannot be found anywhere else in the known galaxy. Under the surface of the planet lies numerous water ways the native Gungans use as pathways to sacred places around the world.

Yavin

This planet is classified as a gas giant, and its core is composed of metallic substances. Pieces of carbon and metallic hydrogen can form corusca gems under the right conditions. This planet is well known for one of its habitable moons where the first Death Star battle took place.

Zonama Sekot

This is another planet considered an enigma in the universe. This planet is sentient, or capable of thought, and can travel through space. Not much else is known about this mysterious planet other than it is also considered a "Seed planet" of the original home world of the Yuuzhan Vong invaders.

Mustafar

This planet is engulfed in lava flow. This is caused by the gravitational stress played on this planet by Jestefad and Lefrani, two gas giants.

Mon Calamari

This is a planet whose surface is 99% covered in water. Home to the Mon Calamari and Quarren, this planet's name is actually Dac; the more commonly used name was derived from Humans.

Coruscant

This is a world covered by one giant city. This world is the center of the galaxy, even to the point that its Hyperspace coordinates are 0,0,0, or more commonly known as "Triple Zero".

Arx

Arx, the new center of the Brotherhood and the Dark Council, is located within the Arx System in the Wild Space region. Situated close to its sun, Arx Primus, the planet is orbited by one moon, Arx Minor, and several man-made satellites. With a slight axial tilt and a circular orbit, Arx experiences a regular seasonal rotation throughout a local orbital period.

Sustaining diverse biomes and a plethora of flora, Arx has a breathable Type-I atmosphere that is saturated with greenhouse gases due to the constant pollution of planetary industries. Due to the constant shifting of tectonic plates, volcanic activities and the concentration of crystals being released from the planet’s crust in certain regions, Arx’s climate varies from continent to continent. Storms are commonplace over the oceanic regions as submerged kyber crystals are released from the planet’s crust to ionize the atmosphere, in addition to the calm, warm ocean waters creating convection currents in the air above the surface.

4 - Stars

A star is a massive body of plasma that is currently or has produced energy through nuclear fusion. Unlike a planet that only reflects light, a star actually emits it because of their heat. In this section, I will go through the various stages of a star's life. Stars are born in nebulae, come in various sizes and have life spans of billions of years. Their temperature also varies, with red and yellow stars being cooler than white and blue stars. Stars begin as protostars and after "ignition," they begin to grow and burn brighter. We will look at the typical life span of a yellow star, which is a medium range star and fairly common in the galaxy.

Yellow Star

One of the more common types of stars in the universe, the normal surface temperature of one of these stars normally runs approximately 5,500 K. These types of stars near the end of its existence will normally expand into a Red Giant, sometimes engulfing the planets closest to it. At a minimum, any planets orbiting the star will face climate changes.

Red Giants

These are stars that can grow up to 8 times the mass of a normal Yellow Star. These stars come into existence near the end of a yellow star's life span when the yellow star exhausts its source of hydrogen.

White Dwarfs

These stars are when a low to medium massed star dies, and cannot support the temperatures necessary for fusion. These stars slowly cool in space until they are no longer visible.

5 - Galactic Phenomena

This section will cover oddities within the galaxy that have puzzled astrophysicists. This will range from black holes and their clusters (i.e. The Maw) and the Dark Shroud. I must warn you that information on this subject can change at any time due to the fact that new discoveries are made every standard day.

Black Holes

A black hole is a concentration of gravity so strong that no force can escape its grasp, not even light, hence the name. These are formed when a star creates so much gravity that it collapses in on itself, at this point an "Event Horizon" is formed. This is the point where nothing can escape from the gravity of this object. Theories of what lies on the other side of a black hole abound, but the current level of technology makes it impossible to successfully penetrate a black hole.

Maw Cluster

Located near the planet Kessel, the Maw Cluster is an unstable and mostly unnavigatable cluster of black holes; it is the only known such anomaly. There is only one known safe point within this beast, it was used for the construction of the Death Star prototype and the Maw Installation, and all other areas are saturated in radiation, plasma, and strong gravitational forces. In order to navigate through the area, precise maps are required. Also, a Jedi may also navigate the area without a map, but usually at a drastically reduced speed. Also, this is where Han Solo was able to shave a few space distances off his Kessel Run.

The Shroud of the Dark Side

The Dark Shroud is a nebulous cloud of ionized particles that prohibits easy hyperspace travel in and out of Antei. Its effects are exacerbated by the Dark Side, but it's not a force anomaly on it's own. There is limited hyperspace travel in and out of the shroud; however, only those that know the way are truly safe. Many foolish adventurers have attempted to navigate the shroud; to date, no one has successfully done so.

6 - Navigation

Navigation throughout the galaxy can be accomplished a variety of ways, but we will discuss three of the most common: navigational computers, astromechs, and force astrogation.

Navigation Computer

The first is the Navigational Computer, or the Naviputer. This machine has without a doubt been the largest boon to space exploration (barring the hyperdrive) in the known galaxy. In a matter of seconds this computer can calculate all known gravity wells, planetary orbits, star placements, and system rotations in the galaxy. However, this finely tuned piece of electronics is prone to electrical interference. This can be anything from a graze of an ion blast, having more than one computer running, or just shoddy maintenance. Jumping without the computer can lead to you coming out inside planets, stars, black holes, or not coming out at all.

It is important to note that this system has failed each time an adventurer has attempted to leave the galaxy. The reason for this is unknown, but it is suspected that it is due to immense electrical storms around the borders of the galaxy that short out the equipment.

Astromechs

These are handy droids to have in any situation. They can hack into almost any file system, repair damaged vehicles, and even substitute for a Naviputer. While their systems cannot hold a fraction of the information that a traditional naviputer can, they are hardwired with routes through major trade lanes and can be uploaded with a few of the routes. Again as is stated above with Naviputers, these are electronic systems and are prone to electrical interference. However many droid manufacturers have installed breakers of sorts that allow the droid to take a stronger jolt than a traditional computer. All they need is a manual restart from their owner.

Force Astrogation

Everyone knows that Force users can do many mystical feats. However not many know that inside every trained Force user is an organic naviputer. As the Force allows any user to sense life, they can in turn use this power to sense routes of planets, stars, and, to an extent, black holes, and thus allowing them to crudely calculate hyperspace routes. However one doing so must travel at a greatly reduced speed to allow for minor course changes. Being off even a single degree could cause one to be several hundred light years off when they exit hyperspace.

7 - Non-Planetoid Space Matter

Asteroids

These bodies are called "minor planets" by many astronomers, and means "star like". They are formed by left over matter left when the planets within the system were formed. They can also be formed from broken comets. These objects pose the highest risk to any habitable planet. If impact occurs catastrophic effects such as mega-tsunamis to clouds of dust covering the planet reducing sunlight. However, most are picked up by in-system sensor sweeps and can be quickly destroyed by warships.

Asteroids are most commonly used by mining corporations for various minerals and are easily discarded. Pirates and smugglers also use these for bases. Smugglers Run is a representation of this.

Comets

Comets are loose collections of ice, dust and small particles picked up from around any system and orbit the systems sun as gravity allows. As the comet approaches the star it exhibits a visible coma, similar to an atmosphere, and a tail. This is primarily from the effects of solar radiation on the comets nucleus; the tail will always point away from the orbiting star and are made of ion gases. It can also stretch upwards of 1 Astronomical unit (AU).

The nucleus itself can measure a few kilometers to tens of kilometers across. It is also composed of rock, interplanetary dust and ice. The nucleus of a comet is among the darkest objects in the known universe. They can absorb up to 98% of the light that falls upon it. In comparison duracrete used in making roadways absorb about 93% of light.

8 - Conclusion

I hope you have learned much by reading these notes. I must apologize for not being able to go into much detail on some subjects. Most are vast, and just one subject would constitute as much information if not more as these notes. If this course has interested you I would highly recommend following up on the Holonet under the URL of wikipedia.com or searching one of these subjects in your search engines.