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Sent primarily to investigate the origin and evolution of Jupiter, Juno has been able to take in bonus observations of the planet's four major moons - Callisto, Ganymede, Europa and now Io. It performed its close flyby of Ganymede in 2021, and of Europa earlier this year. These passes produced some novel insights from Juno's microwave radiometer. Intended to look deep into the clouds of Jupiter, this instrument has also been able to see down through the ice layers of Ganymede and Europa for tens of kilometres. These two moons are of particular interest because they're both thought to hide...

In the early 1960s, scientists developed the gravity-assist method, where a spacecraft would conduct a flyby of a major body in order to increase its speed. Many notable missions have used this technique, including the Pioneer, Voyager, Galileo, Cassini, and New Horizons missions. In the course of many of these flybys, scientists have noted an anomaly where the increase in the spacecraft’s speed did not accord with orbital models. This has come to be known as the “flyby anomaly”, which has endured despite decades of study and resisted all previous attempts at explanation. To address this, a team of researchers...

NASA made the decision to leave the Juno spacecraft, currently orbiting Jupiter, in its current orbit that cycles around the gas giant every 53 days. The choice hinges on worries surrounding Juno's main engine, which displayed some out-of-the-ordinary readings as the team was preparing to shorten the probe's orbit. “Juno is healthy, its science instruments are fully operational, and the data and images we’ve received are nothing short of amazing,” said Thomas Zurbuchen, associate administrator for NASA’s Science Mission Directorate in Washington. “The decision to forego the burn is the right thing to do – preserving a valuable asset so...

NASA's Juno Jupiter probe won't be settling into its final orbit around the giant planet this week after all. Juno was scheduled to fire its main engine for the final time during the probe's close Jupiter flyby on Wednesday (Oct. 19), in a maneuver that would reduce the time it takes the spacecraft to circle the gas giant from 53 Earth days down to 14 days. But the mission team decided to postpone the burn in order to investigate an issue with valves that are part of Juno's fuel-pressurization system, NASA officials said. "Telemetry indicates that two helium check valves...

The San Diego-made camera aboard the Juno spacecraft survived in good working order when the satellite went into orbit around the gas giant on July 4th. NASA on Tuesday released the first image taken by "JunoCam" since the satellite began its primary mission of studying Jupiter's physical and chemical composition. The two megapixel camera developed by Malin Space Science Systems was turned off for operational reasons shortly before Juno entered orbit. But NASA switched the camera back on on July 10th and took a low resolution image that shows half of Jupiter and three of its moons, Io, Europa and...

18:19 Juno should now be starting a slow maneuver from its power-generating sun-pointing attitude toward the orientation required for tonight's Jupiter Orbit Insertion burn. This slow precession maneuver should take about 21 minutes, then Juno will hold its position before starting a faster precession to the burn attitude. 17:56 Last pre-JOI image from JunoCam Here is the official caption from NASA: "This is the final view taken by the JunoCam instrument on NASA's Juno spacecraft before Juno's instruments were powered down in preparation for orbit insertion. Juno obtained this color view on June 29, 2016, at a distance of 3.3...

As Juno nears Jupiter tonight, the giant planet's powerful gravity will accelerate the spacecraft to an estimated top speed of about 165,000 mph (265,000 km/h) relative to Earth, mission team members said. "I don't think we've had any human[-made] object that's moved that fast, that's left the Earth," Juno principal investigator Scott Bolton, of the Southwest Research Institute in San Antonio, said during a news conference last week. The all-time speed record is currently held by NASA's Helios 1 and Helios 2 spacecraft, which launched in the mid-1970s to study the sun. Both probes reached top speeds of about 157,000...

Explanation: Approaching over the north pole after nearly a five-year journey, Juno enjoys a perspective on Jupiter not often seen, even by spacecraft from Earth that usually swing by closer to Jupiter's equator. Looking down toward the ruling gas giant from a distance of 10.9 million kilometers, the spacecraft's JunoCam captured this image with Jupiter's nightside and orbiting entourage of four large Galilean moons on June 21. JunoCam is intended to provide close-up views of the gas giant's cloudy zoned and belted atmosphere. On July 4 (July 5 UT) Juno is set to burn its main engine to slow down...

Explanation: What will NASA's Juno spacecraft find when it reaches Jupiter next Monday? Very little, if Juno does not survive Jupiter Orbit Insertion, a complex series of operations in an unknown environment just above Jupiter's cloud tops. If successful, as explained in the featured video, Juno will swoop around Jupiter, passing closer than any previous spacecraft. The goal is to decelerate, enter into a highly elliptical orbit, and begin two years of science operations. Juno's science mission objectives include mapping Jupiter's deep structure, determining how much water is in Jupiter's atmosphere, and exploring Jupiter's powerful magnetic field and how it...

...July 4, Juno must fire its main engine for 35 minutes. ... will place NASA’s robotic explorer into a polar orbit around the gas giant. The approach over the north pole is unlike earlier probes that approached from much lower latitudes nearer the equatorial zone, and thus provide a perspective unlike any other. ... ... Juno will fly within 2,900 miles (4,667 kilometers) of the Jovian cloud tops. All instruments except those critical for the JOI insertion burn on July 4, will be tuned off on June 29. That includes shutting down Junocam. “If it doesn’t help us get into...

Explanation: Next stop: Jupiter. Last week included one of the few times in history that humanity launched something completely off the Earth, moving away so fast that it will never return. Well, almost -- Juno's planned trajectory actually brings it homeward bound in about two years, zipping by, this time using the Earth's gravity to pull it to an even higher speed, high enough to reach Jupiter. The above video depicts the launch of Juno aboard a Atlas V rocket. When the robotic Juno spacecraft reaches Jupiter in 2016, it will spend just over a year circling the Solar System's...

Jupiter is a big, complex, chaotic planet. It has long been known as the most dominant feature in our sun’s orbit, but it wasn’t until last May that the planet’s internal features began to be revealed. During a few close passes, NASA’s $1.1 billion Juno spacecraft collected data on the gas giant that revealed cyclones the size of Earth and a surprisingly strong magnetic field. Now, data collected by Juno have uncovered more never-before-seen features on its north and south poles. In a study published this week in the journal Nature, a team of scientists report bizarre geometric storms surrounding...

Jupiter's south pole is seen in a series of time-lapse images taken by NASA's Juno spacecraft during its 11th close flyby of the giant planet on Feb. 7, 2018. Credit: Gerald Eichstadt/NASA/JPL-Caltech/SwRI/MSSS You've never seen Jupiter's south pole quite like this. A new photo by NASA's Juno spacecraft show Jupiter's south pole as seen from above during a recent close encounter on Feb. 7. The photo is actually a series of images taken over time by Juno as the probe whipped around Jupiter during its 11th flyby of the giant planet.   ... The time-lapse views of Jupiter were taken over...

“In truth, the GRS has been shrinking for a long time,” Glenn Orton of NASA’s Jet Propulsion Laboratory told Business Insider. The storm was once as large as four times the diameter of Earth, but more recent observations have shown that it’s rapidly losing steam. “Now it’s something like 13 degrees wide in longitude and only 1.3 times the size of the Earth,” Orton says. “Nothing lasts forever.” Late last year, Juno revealed some surprising information about the huge storm, including how deep into the planet it goes. The data showed that the storm is up to 100 times deeper...

A stunning new Nasa image shows raging storms on Jupiter with clouds that stretch for thousands of miles - and it looks just like an oil painting. Nasa's Juno spacecraft was a little more than one Earth diameter from Jupiter - or 8,292 miles (13,345 kilometres) - when it captured this mind-bending view of the planet's tumultuous atmosphere. The incredible colour-enhanced image was captured at a latitude of 48.9 degrees and depicts vasts swirling cloud formations that travel at about 129,000 mph (60 km/s) over the gas giant planet's surface. The spacecraft, which has been orbiting the planet since 2016,...

Jupiter’s gravity field varies with depth, which indicated that material is flowing as far down as 3,000 km (1,864 mi). Combined with information obtained during previous perijoves, this latest data suggests that Jupiter’s core is small and poorly defined. This flies in the face of previous models of Jupiter, which held that the outer layers are gaseous while the interior ones are made up of metallic hydrogen and a rocky core. ... Another interesting find was that Jupiter’s gravity field varies with depth, which indicated that material is flowing as far down as 3,000 km (1,864 mi). Combined with information...

As part of its sixth orbit of Jupiter’s turbulent cloud tops, Juno passed close to Jupiter’s center (aka. perijove), which took place at 6:55 p.m. PDT (9:55 p.m. EDT). Eleven minutes later – at 7:06 p.m. PDT (10:06 p.m. EDT) – the probe flew over the Great Red Spot. In the process, Juno was at a distance of just 9,000 km (5,600 miles) from the anticyclonic storm, which is the closest any spacecraft has ever flown to it. During the flyby, Juno had all eight of its scientific instruments (as well its imager, the JunoCam) trained directly on the storm....

The original plans for the Juno mission to Jupiter didn’t include a color camera. You don’t need color images when the mission’s main goals are to map Jupiter’s magnetic and gravity fields, determine the planet’s internal composition, and explore the magnetosphere. But a camera was added to the manifest, and the incredible images from the JunoCam have been grabbing the spotlight. ... Hundreds of ‘amateur’ image processing enthusiasts have been processing raw data from the JunoCam, turning them into stunning images, many reminiscent of a swirling Van Gogh ‘starry night’ or a cloudscape by Monet. ... Many of the images...

Early science results from NASA’s Juno mission to Jupiter portray the largest planet in our solar system as a complex, gigantic, turbulent world, with Earth-sized polar cyclones, plunging storm systems that travel deep into the heart of the gas giant, and a mammoth, lumpy magnetic field that may indicate it was generated closer to the planet’s surface than previously thought. “We are excited to share these early discoveries, which help us better understand what makes Jupiter so fascinating,” said Diane Brown, Juno program executive at NASA Headquarters in Washington. "It was a long trip to get to Jupiter, but these...