By Chris Hanko
Astronomy is a place where curious minds thrive, and are often rewarded with amazing, seemingly improbable discoveries. While we have come so far in terms of knowledge and technology, there is still so much for us to learn about our surroundings and even our very existence. In this article, I will guide you through a brief, and extremely paraphrased, version of some of the things we have discovered about the Universe since the Wisconsin Engineer Magazine published its first issue in 1896.
1896 is a year that seems archaic to some, but in the relative spectrum of recorded history, it is not that distant from today. Although humans have been on this planet for roughly 200,000 years, it was only in the last century that we have made the most significant advancements in our knowledge of the Universe. One of first advancements was in 1901, when Annie Jump Cannon proposed a way to categorize stars and other phenomena by the absorption lines in their spectra, a method that is still being used today. This revolutionary method was then complemented by Ejnar Hertz in 1906 when he established a standard for measuring star brightness, which helps us identify how far away stars are, and even the composition of stars.
Over a decade later, physicist Karl Schwarzschild utilized Einstein’s theory of general relativity to begin work on the black hole theory. He proposed that for any star with a certain diameter and density, its gravity will be so strong that any forms of radiation or light will not be able to escape. Seven years later, Edwin Hubble discovered a star in what is now called the Andromeda galaxy, providing proof that our galaxy is not singular. Two years after that finding, Hubble produced a successful galaxy classification system. By 1926, the first liquid fuel-powered rocket was launched and broke the sound barrier for the first time. Our power continued to grow exponentially as humans began to push the bounds of what was once possible.
By the year 1932, Karl Jansky detected the first radio waves from space, and about seven years later, astronomers identified the source. The source was coming from galaxies Centaurus A and M87, a revolutionary discovery as this is the first documentation of radio waves originating from outside our galaxy. One of the most important discoveries was the discovery of how stars generate energy. In 1938, physicist Hans Bethe outlined a sequence of nuclear reactions, which converted hydrogen into helium, and in turn, released large amounts of energy. This reaction sequence occurs slowly, allowing stars to burn for billions of years. The next substantial advancement was the development of the V-2 rocket powered ballistic missile. During the same timeframe of this technological advancement came the completion of the largest telescope in the world in California which boasted a 200-inch mirror, allowing humans to view the cosmos on a greater scale than ever before.
Just over six decades since the publication of the first Wisconsin Engineer Magazine issue, the famous Sputnik 1 was launched into orbit by Russia, thus beginning the era of the space-race. Four months after Sputnik 1, the US launched Explorer 1 into space. This launch inspired the creation of the National Aeronautics and Space Administration (NASA). About a decade later, the United States made history when Neil Armstrong became the first human to step foot on the moon.
In 1970, about 75 years since the advent of the Wisconsin Engineer Magazine, NASA launched the Uhuru satellite into space with intentions to map the sky with x-ray wavelengths. The satellite successfully charted many x-ray sources, including black holes, which gave preliminary evidence of their existence. By 1975, the Russian probe Venura 9 landed on the surface of Venus and became the first probe to land on another planet. Within a year after that, two NASA probes, Viking I and Viking II, successfully landed on Mars in search of signs of life. By 1977, the Voyager 2 was launched to study the Jovian, Saturnian, Uranian, and Neptunian systems as well as the Kuiper belt, a collection of space objects creating the boundaries of our heliocentric solar system.
In 1983, the first infrared satellite (IRAS) completed a survey of 98% of the visible sky during a 300-day journey. NASA experienced catastrophe in 1986 when the Challenger space shuttle exploded shortly after its launch. Following the disaster, NASA began to demonstrate extreme caution, halting and nearly shutting down operations. However, failure and curiosity only gave the organization more fuel. In the two decades following the mission, the Magellan, Galileo, and Cassini probes successfully landed on Venus, Jupiter, and Saturn respectively. Around the same time, the Hubble Space Telescope was launched, which has continued to produce fantastic images of distant stars, nebulae, and galaxies.
1992 — Present:
As we pushed closer towards the 21st century, the number of innovations continued to mount. In 1992, the Cosmic Explorer satellite produced a detailed map of the radiation from the Big Bang, the new 10-meter Keck Telescope was finished, and the first computer-controlled alignment telescope was produced. In 1998, the groundwork was laid for the International Space Station, between former space-race rivals US and Russia. More recently, around 2005, Dr. Mike Brown was credited with finding a dwarf planet, near the Kuiper belt, that he called Eres. This discovery changed the guidelines for how we distinguish planets and dwarf planets, which brought upon the question if Pluto should be classified as a planet. The most recent scientific debate is pertaining to the newly-theorized Planet Nine hypothesis, and it will be interesting to see how that unfolds, as we may never look at our solar system the same way again.
Now that we have finished our brief journey through time and space, it is not hard to tell how far we have come in the understanding of our universe since the first issue of the Wisconsin Engineer Magazine was published. While we have learned so much, there is still so much to discover. As world-renowned astrophysicist Neil deGrasse Tyson once said, “Space exploration is a force of nature unto itself that no other force in society can rival.”