Earth 2.0
Author: Giles Ru'Orden
The stars and the night sky have been an integral part of humankind ever since evolution entitled us to functioning brains and eyes. The beauty, mystery, and consistency of these outer earthly bodies have allowed us to navigate uncharted environments and share special moments with the people we care about.
As grandiose as these few examples may be, the simple truth is that outer space and all that it contains, provides us with a sense of unity, pride, and the key to our future as a race. Moreover, the drive to understand and explore what is out beyond our planet would not be possible without the technology that has been developed over the course of history.
After World War II, political ideologies and allegiances of various nations left the Soviet Union and the US in the middle of a space race, leaving concerns for US national security. The pressure of security escallated when the Soviet Union was the first country to put an object (artificial satellite Sputnik 1 -1957) into orbit. As a consequence of this, in October 1958, the National Aeronautics and Space Administration was formed as a conglomerate of various research institutions in the United States. This brought a central hub to American advancement in space and contributed to a recovery in what American people saw as technological deficit. After 11 years of contest, the United States made a giant leap forward when they landed a man on the moon.
Since the Apollo missions, there has been many positive steps forward (and some backward) with respect to space exploration and understanding what is truly beyond our earthly borders. Satellites are analyzing the Earth's atmosphere, the moon, and other planets in our solar system. Rovers are analyzing the surface of Mars and streaming back huge amounts of data. Giant telescopes on and off Earth are taking pictures and observing extrasolar entities yielding an immense volume of data and interesting findings. However, the issue is that spending large sums of money with very little immediate effect is difficult for certain people to justify. What is unfortunate is that people most often forget about one underlying factor, the Earth will not be able to support humanity forever. Enter Kepler.
The excitement around the quest to find other worlds like Earth has recently increased due to the discovery of hundreds and thousands of planets orbiting other stars in our galaxy. These newly discovered planets mainly consist of three types; gas giants, hot-super-Earths (have more mass than Earth, but lower than gas giants) and Ice giants. Despite finding these entities, the challenge is finding terrestrial planets (those that might contain liquid water on the surface) in a habitable zone (area where water won't boil or freeze). The Kepler mission has been implemented to survey the nearby portion of our Milky Way galaxy in order to find those terrestrial planets in the habitable zone. So what is Kepler and how is it used to determine the size of a planet and whether or not it is habitable?
When a planet crosses in front of a star, it is called a transit. This transit is seen as a small black dot moving across a star (an example of this observed from Earth is when Mercury or Venus cross between us and the Sun, blocking the sunlight). The Kepler instrument, named after Johannes Kepler, is a large telescope that measures light (photometer). It finds planets by looking at tiny reductions in brightness when planets pass in front of the star it orbits. And from this, the planets orbital size can be determined by the amount of time it takes the planet to orbit once around the star and by the mass of the star using Kepler's Third Law of planetary motion. The size of the planet can then be determined by observing the drop in brightness when the planet transits a star. Putting these attributes together can provide a decent understanding of how habitable a planet might be. The photometer must be kept in space in order to avoid interruptions due to day-night cycles, seasonal cycles, or other atmospheric disruptions. This naturally leads us to wonder whether or not the Kepler instrument has actually found anything useful.
Since March 2009, Kepler has found and confirmed 61 planets that are potentially habitable. Most recently, a planet called GJ 667Cc has been discovered and is believed to be the best candidate to contain water and possibly life. Despite it being 4.5 times as massive as Earth and that it only takes 28 days to orbit around its parent start, the amazing feature is that this planet is only 22 light-years away and it is right in the middle of the habitable zone. To date, this is the closest habitable planet to Earth. Another find from Kepler occurred only days after its began its scientific operation in 2009. The planet named Kepler 22b is located 600 light-years away and is about 2.4 times the size of earth. However, this planet orbits its parent star in a highly elliptical orbit which yields more severe temperature fluctuations. Despite this, the planet is still located in the habitable zone.
As humans, we have an insatiable desire to explore new places. These few examples highlight the importance of how technology can help advance our understanding of the worlds around our own. Moreover, it is even more important that we are taking the necessary steps forward to provide humanity with options to prepare for an eventual certainty, running out of land and resources. The only issue at hand is that we do not have the technology to deliver humans to those target sources for hands on exploration. But when we think about it, the internal combustion engine was only invented back in 1859. A mere 150 years ago. On top of that fact, remember that the first artificial satellite was launched in 1957. A mere 50 years ago! Even though we may not see humans land on GJ 667Cc in our lifetime, we certainly will see them land on a planet much like it in the not too distant future and how exciting that will be. Imagine it. Landing on a strange new planet, seeing the night sky harbor strange new stars (two stars a la Tatooine - which is a real discovery), and bringing about strange new questions that will be asked by those gazing up up into it. How wonderful it would be to colonize Earth 2.0.
