The Juno Probe

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The Juno probe successfully made it to an orbit around Jupiter after the five year journey on July 4th. This spacecraft/probe has reached Jupiter with no hiccups in the journey to the largest planet in the Solar System and will enable humanity to see what has never been seen of this complex region, collecting data which could greatly inform scientific theory. The key focus of Juno is to learn and understand the evolution and origins of Jupiter, and to peer behind the dense veil of clouds. This mission has been a hallmark of success, efficiency, and the use of increasingly amazing technology. 

Mission to Jupiter

The mission overview for the Juno probe is multifaceted, and a continued investment in the awareness of the various complexity of the Milky Way. The four key mission objectives of Juno are to;

(List redacted for preview. Available via download).

This presents a fantastic challenge balanced with incredible opportunity, to which the NASA program has been working since its inception. Jupiter is magnificently large, “It has an equatorial radius of 71,492 km, which is 11.2 times larger than Earth's...In fact, it accounts for 2.5 times as much mass as all of the other planets in the Solar System” (Coffey). Preliminary study of the environment and context of Jupiter discovered, the planet is constantly feeding off of its moons to create a little known ring system. The rings are so faint that it wasn’t until the flyby of Voyager 1 that they were discovered. The “Main” ring is about 7,000 km wide and has an outer boundary 129,130 km from the center of the planet. (Coffey). No doubt now with Juno in place armed with and clear camera and spectral array humanity will begin to get a much clearer picture of this diverse planet and its surrounding space. 

Juno has been specially equipped to probe under the dense cloud cover with hides the mysteries of this giant. This fundamental purpose is what got Juno its name which has been taken from Roman and Greek mythology. In this pantheon, the god Jupiter purposely drew a veil of clouds around himself to hide his mischievous deeds. Jupiter’s wife, the goddess Juno, was the only one equipped to see through the veil of clouds to reveal Jupiter’s true nature (NASA). This name helps keep the mission objective in perspective. 

Desire to See to the Core

The Big Bang theory has a lot of holes, which they hope to fill with data collection and analysis. Scientists believe, “Underneath its dense cloud cover, Jupiter safeguards secrets to the fundamental processes and conditions that governed our solar system during its formation” (NASA). Understanding the evolutionary path of any body in the solar system can go a long way towards filling in the gaps in the Big Bang theory. As such, theories about solar system formation all begin with the collapse of a giant cloud of gas and dust, or nebula, most of which formed the infant sun. Like the sun, Jupiter is mostly hydrogen and helium, so it must have formed early, capturing most of the material left after our star came to be. (NASA)

Currently, scientists do not understand how this occurred. Questions abound, and only more specific data can help point analysts in the right direction. Such questions that Juno hopes to aid as, “Did a massive planetary core form first and gravitationally capture all that gas, or did an unstable region collapse inside the nebula, triggering the planet's formation? Differences between these scenarios are profound” (NASA). After the journey to the planet, Juno entered the atmosphere during a 35-minute engine burn to slow down the probe. This occurred at Earth time at 8:53 pm. PDT (11:53 p.m. EDT) on Monday, July 4th, 2016. A fortuitous day; ‘Independence Day always is something to celebrate, but today we can add to America’s birthday another reason to cheer – Juno is at Jupiter,’ said NASA Administrator Charlie Bolden. ‘And what is more American than a NASA mission going boldly where no spacecraft has gone before? With Juno, we will investigate the unknowns of Jupiter’s massive radiation belts to delve deep into not only the planet’s but into how Jupiter was born and how our entire solar system evolved.’ (NASA)

The flight plan was right on, and only a small planned correction shifting Juno’s attitude to direct the main engine in the correct direction, and then increasing Juno’s rotational rate from 2 to 5 revolutions per minute (RPM) to help stabilize it was required for this first part of the mission to be successfully completed (NASA). This correction was needed due to the incredible gravity of Jupiter, which greatly affected Juno. Rick Nybakken, Juno project manager from NASA’s Jet Propulsion Laboratory explains, "as planned, we are deep in the gravity well of Jupiter and accelerating. Even after we begin firing our rocket motor, Jupiter will continue to pull us, making us go faster and faster until we reach the time of closest approach. The trick is, by the end of our burn, we will slow down just enough to get into the orbit we want." (NASA)

The atmospheric entry, called Jupiter orbit insertion (JOI) was the final aspect of the Juno mission which required special attention and supreme technical specificity. Rick Nybakken, Juno project manager from JPL, reported, “The spacecraft worked perfectly, which is always nice when you’re driving a vehicle with 1.7 billion miles on the odometer” (NASA). Progress is being made at phenomenal rates in all areas of human technology and application. During the time in-between launching Juno, and arrival, the team figured out how to boost productivity. Bolton shares, “official science collection phase begins in October, but we’ve figured out a way to collect data a lot earlier than that. Which when you’re talking about the single biggest planetary body in the solar system is a really good thing” (NASA). It can only be suspected that this is the first of many fine tunings and applications of space technology which will reap incalculable rewards.

The Juno mission was launched from Cape Canaveral Air Force Station in Florida on Aug. 2011. Juno is an integral aspect of NASA’s New Frontiers Program, which is managed at NASA's Marshall Space Flight Center in Huntsville, Alabama, which is part of the agency’s Science Mission Directorate. The Juno spacecraft cost $1.1 billion and is a representation of the finest space tech available (Kofsky). This is a relatively short mission plan, as “Juno's mission is planned to last for a much shorter period, as it is currently being targeted to impact Jupiter in February 2018” (Howell). Scientists involved believe that this short time will be enough to gather the data they need to have a better understanding of the planet, and will likely be the first of many specialized probes. Juno is and prepared for its journey with the finest instrumentation (Chang). 

Many Firsts

The first of many firsts, Juno captured video footage of the four Galilean moons (Callisto, Europa, Ganymede and Io) orbiting Jupiter. This greatly excited the scientists who had been anticipating the first, saying that in “’all of history, we've really never been able to see the motion of any heavenly body against another,’ Juno principal investigator Scott Bolton said Monday night during a news conference here at NASA's Jet Propulsion Laboratory after Juno’s successful arrival” (Wall). Scientists call Jupiter the King of the solar system, and to be able to see the king’s court after so long is very fulfilling. Much mystery is about to be uncovered in Juno’s effort.  

Currently the Juno probe is skimming the cloudy atmosphere of Jupiter, and is ready to begin transmitting close-up views and data of the giant. The first images have already revealed surprises, as “Jupiter's second-largest moon, Callisto, appeared dimmer than initially thought” (Kofsky). Unlike past probes, Juno will take a series of risky dives beneath Jupiter’s intense radiation belts where it will study the gas giant from as close as 2,600 miles over the planet's cloud tops. Galileo, the last mission to the gas giant that ended in 2003, spent most of its mission five times farther away than Juno will get. (Kofsky)

This is the closest flyby of Jupiter yet, and may explain why the mission plan is so short. That distance is highly risky, and may not leave the probe unscathed and able to function optimally. No matter what occurs the data that will be gained will help specialize future probes.  However, close up shots of the Red Giant must be worth it, as “There's also the mystery of its Great Red Spot. Recent observations by the Hubble Space Telescope revealed the centuries-old monster storm in Jupiter's atmosphere is shrinking” (Kofsky). So far the project has been an incredible success. The project organizers are joyous, “’Juno sang to us and it was a song of perfection,’ JPL project manager Rick Nybakken said during a post-mission briefing. The possibilities for the growth of awareness, and a stronger sense of how humanity fits into the diverse solar system may be just around the corner. 


The Jupiter probe Juno offers the promise of incredible new views of the great giant, and its moons, and subtle ring systems. The space program has become highly specialized, and the technology it employs to accomplish data harvesting of some of the most complex questions humanity faces is incredibly refined and becoming more so every day. Within the short time Juno travels in Jupiter’s orbit no doubt the understanding of the planet, its origins, and its environment will be considerably informed. How this data will apply to lingering and pressing questions about the origins of life on Earth remain to be seen, but there is no doubt it will be an amazing show.

Works Cited

Chang, Alicia. “NASA Spacecraft Reaches Jupiter.” U.S. News, 5 July 2016. Retrieved from:

Coffey, Jerry. “How many Earths can fit in Jupiter?” Universe Today, 24 Dec. 2015. Retrieved from:

Howell, Elizabeth. “Juno Spacecraft: NASA's New Mission To Jupiter.”, 5 July 2016. Retrieved from:

Kofsky, Michael. “NASA's Juno poised to begin transmitting close-up views of Jupiter.” USA Today, 5 July 2016. Retrieved from:

NASA. “Juno.”, 2016. Retrieved from:

 NASA. “Juno Spacecraft in orbit around mighty Jupiter.”, 4 July 2016. Retrieved from:

Wall, Mike. “Jupiter Probe Captures First-Ever View of Moons Moving.”, 5 July 2016. Retrieved from: