Jupiter – Astronomy of Planets

As the biggest planet in our solar system, Jupiter has sparked the curious minds of people for centuries. Among the many mysteries surrounding Jupiter, its interior remains one of the most fascinating secrets that we seek to understand. Although there is no certainty, it is widely accepted that Jupiter has a core and we will explore theories about its composition that support this theory. The spacecraft, Juno, is currently orbiting Jupiter to delve deep in discovering the planet’s evolution and atmosphere, sending back information that continues to amaze peoples minds. Jupiter’s core and composition will be assessed to determine what really lies in Jupiter’s interior and for the possibility of the core being composed of dense materials instead of solids.

Magnificently separated from us by millions of kilometers and an asteroid belt, Jupiter has fascinated humanity for thousands of years. Today, we have learned more than Galileo could have hoped to learn when he first saw Jupiter through his rudimentary telescope in 1610, revolutionising scientific thinking, and our understanding of the Universe by providing evidence for the heliocentric model. It is truly astounding what we know of this gas giant, given that its average distance from the Sun is five times that of Earth’s. We are using methods such as spectroscopy to remote sense attributes of the planets, but in order to gain an appreciative understanding of Jupiter, it is important to understand how we are able to determine these characteristics. It is from this that we aim to answer the question: how has our understanding of Jupiter changed with the use of modern technology. Through this investigation, topics that will need to be discussed include an explanation of spectroscopy, the scientific probes that have used these methods to discern the contents of Jupiter’s atmosphere, the work their predecessors completed, and the implications this has for humanity.

Learning about the range of wavelengths of light and how emission and absorption lines in spectra are analyzed is paramount to understanding how we know anything about the composition of Jupiter’s atmosphere from such a great distance. A brief history of the methods used to investigate early hypotheses for Jupiter’s chemical composition from the late 1800s will be discussed to give a perspective of how the scientific method has been used to study it in the past. As well, past space missions to Jupiter, such as the Galileo probe, will be discussed. The Juno probe, launched in 2011, will also be investigated, with a focus on its ultraviolet spectrograph.

Since mankind has first looked up at the night sky, we have been filled with a sense of awe, wonder, and curiosity. For millennia humanity has looked up at Jupiter the same way and, as more is learned about the Jovian planet, these feelings only grow stronger. Jupiter more closely resembles a star than a terrestrial planet in composition, and indeed, if it had only been around 80 times more massive, it would have become a star rather than remaining a gas giant. In comparison, Jupiter is 318 times more massive than Earth. With Jupiter’s composition, relative size, and the fact that the planet has four planet-sized moons and many smaller natural satellites, Jupiter is in many people’s minds a kind of miniature solar system in its own right. Jupiter’s enormous size means the planet’s atmosphere is complex and experiences weather systems of unimaginable proportions. Within such a large system, these phenomena are hard to study, but it is theorized that energy within these extreme weather patterns is actually sourced from within the planet itself, rather than from the sun.

Although the composition of Jupiter is similar to that of our Sun, it failed to ignite in nuclear fusion. A nuclear fusion reaction similar to that of the Sun requires extreme gravity to compress the hydrogen down to a point where the extreme pressure and temperature pack the hydrogen atoms into helium, which is the energy source for the sun and most stars. ¹ This is also what makes the Sun burn bright. Despite the fact that Jupiter is made of vast quantities of hydrogen, it is not nearly enough to ignite the planet in nuclear fusion. The minimum amount of mass required for an object to ignite in true nuclear fusion is 80 times that of Jupiter, which is considered to be a red dwarf star.¹ Astronomers draw the line between a brown dwarf, a planet, and a star depending on a variety of factors such as the ignition of nuclear fusion. Although there is a distinction made between Jupiter, brown dwarfs, and stars, one can conclude that there is a definite connection between the planet Jupiter and all stars. This realization begs a variety of questions: Can Jupiter be classified as a star, or as a brown dwarf? Could Jupiter become a star? Could nuclear fusion on Jupiter be triggered, and if so what would happen to our Solar System? This web page will answer these research questions as well as highlight how Jupiter is very similar in composition and structure when compared to a star such as the Sun. We will also explore how Jupiter is ultimately and inherently different from the Sun and all other stars due to its size, orbit, magnetic field, and rotation.

The discovery and study of Jupiter and its moons, Ganymede, Castillo, Io, and Europa have unraveled the mysteries that surround our universe. The heliocentric model which was one of the most revolutionary discoveries in astronomy was made by Galileo through observation and data collection of Jupiter moons. The moons of Jupiter consist of some of the most volcanic activity in the solar system along with promising potential of life. These discoveries have not only increased our knowledge about the universe but also pushed us to innovate and invent technologies to aid these discoveries.

The quest for extraterrestrial life in the universe is one that compels many a curious scientist. Many key points of interest begin to emerge through a general discussion of Jupiter and its moons. The possibility that life may actually exist elsewhere in our own solar system becomes realistic as we delve deeper into one moon in particular; Europa. Reviewing the environmental aspects which establish its potential to support microbial life, as well as the limiting conditions that would inhibit humans from colonizing this moon, we see that the potential for life to exist elsewhere in the universe is more than just science fiction.

Exploring Jupiter’s Interior (Spring 2018)

A Study of Spectrometry and Spectroscopy to Validate the Characteristics of Jupiter (Winter 2018)

Jupiter's Atmosphere (Fall 2017)

Jupiter: An In-Depth Analysis and Comparison to the Sun (Spring 2017)

Jupiter (Winter 2017)

Europa: Is There Life on Jupiter’s Water Moon? (Winter 2016)