There are thousands of photos on NASA’s Astronomy Picture of the Day website, yet one photo seems to stand out among the rest. As I was scanning through the photos, a flash of green light caught my eye and sparked my interest. The picture of this mystical green light shining across the night sky is titled, “Aurora: Curtains in the Sky.” This image was captured on June 19, 1996 by Michael Dolan. Dolan was observing the sky directly above Lake Superior in Minnesota, when he captured the shot of the aurora borealis or “northern lights”. After analyzing the image, I was able to make sense of the comparison to “curtains.” The aurora appears to be a curtain expanding across the night sky. Many individuals know what an aurora looks like, but not as many know what they are and how they are created.
The phrases, “northern” and “southern” lights are the more recognizable terms regarding these lights in the sky. While many stargazers refer to them as the “northern” or “southern” lights, the scientific name is aurora. The aurora was named after the Greek goddess of dawn by Galileo in the year 1619 (“Aurora: Fabled Glowing Lights” 1). However, at this time, not much was known about the mysterious lights. After many years or observations and careful analysis, the definition of an aurora was crafted. According to Voyages to the Stars and Galaxies, “auroras are caused when energetic charged particles from the Sun interact with the Earth’s magnetosphere, and the Sun is more likely to spew out particles when it is active and the sunspot number is high” (Fraknoi, Morrison, and Wolff 150). This definition could only be crafted with the scientific contributions of many astronomers.
The study of auroras has had many important scientific milestones. According to “The Aurora Explained,” the first discovery that contributed to the understanding of auroras came in 1600 when William Gilbert, an English scientist, revealed that the earth was a magnet. After this discovery was made, Jean Jacque Dortous de Mairan was able to prove auroral displays to solar activity in 1774. The next great astronomer to make strides in the study of auroras was Elias Loomis, who was able to identify the auroral zone, or the location in which the light show takes place. In the mid 1800s, Anders Jonas Angstrom was able to distinguish the difference between sunlight and auroral light by using a prism. The measurements of the aurora was unknown until 1910, when Carl Stormer was able to use triangulation to measure the height. As WWII was underway, auroral research grew more significant. Studies were focused on the effects auroras had on radio communication, navigation. As technology advanced, the research on auroras advanced with it. Cameras and satellites were able to be used to discover new aspects of auroras in the northern hemisphere. Perhaps the most significant discovery made through the research of auroras is the discovery made by the Geophysical Institute in 1974. The institute was able to obtain evidence, through aurora observations, that reveals that magnetic fields exist parallel to electric fields (Brown, 1).
According to, “Aurora: Fabled Glowing Lights,” auroras are “caused by collisions between fast-moving electrons from space with the oxygen and nitrogen in Earth’s upper atmosphere” (“Aurora: Fabled Glowing Lights” 2). Electrons that come from the Earth’s magnetic field become excited that create a bright light. So much light is emitted that the aurora can be seen with the naked-eye alone. Auroras appear in different colors depending on which gas the electrons are exciting. The color can range from bright blues and greens, to deep pinks and purples. These auroras can be seen in two locations: the southern auroral oval and the northern auroral oval. The relationship between auroras and the sun offers an interesting aspect to the study of auroras. Auroras illustrate the electric relationship between Earth and the Sun. As previously mentioned, the Sun sends out the energy needed to form auroras, but sunspots play an interesting role in the production of these magnificent light shows. When the sun has a high number of sunspots, auroras are more likely to occur, because the sun is more likely to push out charged particles towards Earth.
Astronomers have made tremendous scientific findings regarding auroras, but there is still much more to discover. According to my research, research has come back inconclusive regarding auroral sounds (“Astronomy Picture of the Day” 1). Some individuals have claimed to “hear” auroras, but it remains a controversial topic. In addition to the study of sound, scientists have extensively studied auroras seen in the Earth’s atmosphere and have extended the studies beyond our own planet. It is now a known fact that Jupiter, Saturn and Uranus have had their own auroras. It can be assumed that any planet with an atmosphere and a magnetic field, such as Earth, will likely experience an aurora. However, researchers may have found a way to use auroral research to discover information never before known. Some astronomers believe that, “since an aurora indicates the presence of an atmosphere, [they] might be able use the presence of auroras to find planets beyond our solar system that could support life” ( “Aurora: Fabled Glowing Lights” 3). Auroral research will continue on for years to come and it seems as though researching planets outside of this solar system is the next step in a long journey of scientific discovery.
...(download the rest of the essay above)