Juno's Two Deep Space Maneuvers are 'Back-To-Back Home Runs'

NASA's Juno spacecraft successfully executed a second Deep Space Maneuver, called DSM-2 last Friday, September 14. The 30 minute firing of its main engine refined the Jupiter-bound spacecraft's trajectory, setting the stage for a gravity assist from a flyby of Earth on October 9, 2013. Juno will arrive at Jupiter on July 4, 2016.

The maneuver began at 3:30 p.m. PDT (6:30 p.m. EDT), when the Leros-1b main engine began to fire. The burn ended at 4 p.m. PDT (7 p.m. EDT). Based on telemetry, the Juno project team believes the burn was accurate, changing the spacecraft's velocity by about 867 mph (388 meters a second) while consuming about 829 pounds (376 kilograms) of fuel.

The burn occurred when Juno was more than 298 million miles (480 million kilometers) from Earth.

Juno executed its first deep space maneuver (DSM-1), one of comparable duration and velocity change, on August 30. Together, both maneuvers placed Juno on course for its Earth flyby, which will occur as the spacecraft is completing one elliptical orbit around the sun. The Earth flyby will boost Juno's velocity by 16,330 mph (about 7.3 kilometers per second), placing the spacecraft on its final flight path for Jupiter. The closest approach to Earth, on October 9, 2013, will occur when Juno is at an altitude of about 348 miles (560 kilometers).

"It feels like we hit back-to-back home runs here with the near-flawless propulsion system performance seen during both DSM-1 and DSM-2." said Juno Project Manager Rick Nybakken of NASA's Jet Propulsion Laboratory in Pasadena, California. "These successes move us closer to being ready for our most critical mission event, the Jupiter Orbit Insertion main engine burn in July 2016. We're not in the playoffs yet, as that will come in 2016 when we arrive at Jupiter, but it does feel fantastic to have hit both of these DSMs out of the park."

Juno was launched on August 5, 2011. Once in orbit, the spacecraft will circle Jupiter 33 times, from pole to pole, and use its collection of eight science instruments to probe beneath the gas giant's obscuring cloud cover. Juno's science team will learn about Jupiter's origins, structure, atmosphere and magnetosphere, and look for a potential solid planetary core.

Juno's name comes from Greek and Roman mythology. The god Jupiter drew a veil of clouds around himself to hide his mischief, and his wife, the goddess Juno, was able to peer through the clouds and reveal Jupiter's true nature.

Illustration credit: NASA/JPL-Caltech

The Big Dipper by Juno

The Big Dipper as imaged on March 21, 2012, by the JunoCam instrument aboard NASA's Jupiter-bound Juno spacecraft.

Photo credit: NASA/JPL-Caltech/SWRI/MSSS Note: For more information, see NASA's Juno Spacecraft Images Big Dipper.

Jupiter Jet Stream

Following the path of one of Jupiter's jet streams, a line of v-shaped chevrons travels west to east just above Jupiter's Great Red Spot. Most of the planet is unfolded here in a single flat map made on December 11 and 12, 2000, when NASA's Cassini spacecraft flew past Jupiter. At the left, the chevrons run into another storm called the South Equatorial Disturbance (SED).

Photo credit: NASA/JPL-Caltech/Space Science Institute

Note: For more information, see Cassini Spies Wave Rattling Jet Stream on Jupiter.

Io

This is the highest resolution color picture taken so far [as of that date] of Jupiter's volcanic moon Io by NASA's Galileo spacecraft. At 3 kilometers (about 2 miles) per picture element, the fiery satellite is seen against a backdrop of Jupiter's cloud tops, which appear blue in this false-color composite. Among the surprises seen on the moon's surface are several small, distinctly greenish patches and subtle violet hues at the cores and margins of bright sulfur dioxide-rich regions (like the one in the lower right). Dark spots, many flagged by bright red pyroclastic deposits, (deposits from explosive ejecta), mark the sites of current volcanic activity. Most of Io's riotous color is due to the presence of sulfur compounds, but the dark materials that make up the flows and calderas are probably silicate rock.

North is to the top of the picture. The images used to construct this composite were taken in the 1-micron, green and violet filters of the solid state imaging camera system on NASA's Galileo spacecraft. The images were taken on March 29, 1998 at a range of 294,000 kilometers (about 183,000 miles).

Photo credit: NASA/JPL/University of Arizona

Jupiter's Great Red Spot

This Voyager 2 image shows the region of Jupiter extending from the equator to the southern polar latitudes in the neighborhood of the Great Red Spot. A white oval, different from the one observed in a similar position at the time of the Voyager 1 encounter, is situated south of the Great Red Spot. The region of white clouds now extends from east of the red spot and around its northern boundary, preventing small cloud vortices from circling the feature. The disturbed region west of the red spot has also changed since the equivalent Voyager 1 image. It shows more small scale structure and cloud vortices being formed out of the wave structures. The picture was taken on July 3, 1979 from 6 million kilometers (3.72 million miles).

Photo credit: NASA/JPL

Rotation of Jupiter

Jupiter observed with the 1 meter telescope at the Pic du Midi observatory and a Basler Scout Camera; images taken between October 10 and October 15, 2011.

Video credit: S2P/IMCCE/OPM/JL Dauvergne/Elie Rousset/Eric Meza/Philippe Tosi/François Colas/Jean Pajus/Xavi Nogués/Emil Kraaikamp

Jupiter and Io

Jupiter's four largest satellites, including Io, the golden ornament in front of Jupiter in this image from NASA's Cassini spacecraft, have fascinated Earthlings ever since Galileo Galilei discovered them in 1610 in one of his first astronomical uses of the telescope. This true-color composite frame, made from narrow angle images taken on December 12, 2000, captures Io and its shadow in transit against the disk of Jupiter. The distance of the spacecraft from Jupiter was 19.5 million kilometers. The image scale of the high resolution image is 117 kilometers per pixel. The entire body of Io, about the size of Earth's Moon, is periodically flexed as it speeds around Jupiter and feels, as a result of its non-circular orbit, the periodically changing gravitational pull of the planet. The heat arising in Io's interior from this continual flexure makes it the most volcanically active body in the solar system, with more than 100 active volcanoes. The white and reddish colors on its surface are due to the presence of different sulfurous materials. The black areas are silicate rocks.

Photo credit: NASA/JPL/University of Arizona

Earth and Moon, by Juno

On its way to the biggest planet in the solar system -- Jupiter, NASA's Juno spacecraft took time to capture its home planet and its natural satellite -- the Moon.

"This is a remarkable sight people get to see all too rarely," said Scott Bolton, Juno principal investigator from the Southwest Research Institute in San Antonio. "This view of our planet shows how Earth looks from the outside, illustrating a special perspective of our role and place in the universe. We see a humbling yet beautiful view of ourselves."

The image was taken by the spacecraft’s camera, JunoCam, on August 26 when the spacecraft was about 6 million miles (9.66 million kilometers) away. The image was taken as part of the mission team’s checkout of the Juno spacecraft. The team is conducting its initial detailed checks on the spacecraft’s instruments and subsystems after its launch on August 5.

Juno covered the distance from Earth to the Moon (about 250,000 miles or 402,000 kilometers) in less than one day's time. It will take the spacecraft another five years and 1,740 million miles (2,800 million kilometers) to complete the journey to Jupiter. The spacecraft will orbit the planet's poles 33 times and use its eight science instruments to probe beneath the gas giant's obscuring cloud cover to learn more about its origins, structure, atmosphere and magnetosphere, and look for a potential solid planetary core.

The solar-powered Juno spacecraft lifted off from Cape Canaveral Air Force Station in Florida at 9:25 a.m. PDT (12:25 p.m. EDT) on August 5 to begin its five-year journey to Jupiter.

Photo credit: NASA/JPL-Caltech

Jupiter from the Ground

Ground-based astronomers will be playing a vital role in NASA's Juno mission. Because Jupiter has such a dynamic atmosphere, images from the amateur astronomy community are needed to help the JunoCam instrument team predict what features will be visible when the camera's images are taken.

This image was acquired by Damian Peach on September 12, 2010, when Jupiter was close to opposition. South is up and the "Great Red Spot" is visible. Two of Jupiter's moons, Io and Ganymede, can also be seen in this image.

Photo credit: NASA/Damian Peach, Amateur Astronomer

What Juno Will See at Jupiter's South Pole

This simulated view of the south pole of Jupiter illustrates the unique perspective of NASA's Juno mission. The spacecraft's polar orbit will allow Juno's camera, called JunoCam, to image Jupiter's clouds from a vantage point never accessed by other spacecraft.

JunoCam was designed to return the best-ever images of Jupiter's pole. It has a 58-degree-wide field of view encompassing the entire polar region. The view illustrated here simulates an image taken 40 minutes before Juno's closest approach to Jupiter. At closest approach, JunoCam's images of Jupiter's cloudtops will have a resolution better than 3.1 miles (5 kilometers).

Illustration credit: NASA/JPL-Caltech/Malin Space Science Systems

Covering Jupiter from Earth and Space

Ground-based astronomers will be playing a vital role in NASA's Juno mission. Because Jupiter has such a dynamic atmosphere, images from the amateur astronomy community are needed to help the JunoCam instrument team predict what features will be visible when the camera's images are taken.

This image was acquired by Freddy Willems on July 26, 2011. The level of detail captured here illustrates how well ground-based astronomers are able to image the planet. The views acquired by Juno's camera, called JunoCam, as the spacecraft travels through its polar orbit provide a unique vantage point not available to Earth-based observers. JunoCam images therefore complement equatorial views like this one, allowing scientists to study the global dynamics of this giant planet's atmosphere. South is up in this image.

Photo credit: NASA/Freddy Willems, Amateur Astronomer

The Launch of Juno

The first video is an "official" video, compiled from several different camera angles and including, toward the end, some animation sequences showing events in the launch sequence that could not be captured with cameras. The second video is a compilation of a number of launch videos from various cameras both on the ground and on board the rocket.

NASA's Juno spacecraft is on its way to Jupiter after being launched aboard an Atlas V rocket from the Cape Canaveral Air Force Station, Florida on August 5 at 11:25 a.m. Eastern. The solar-powered spacecraft will arrive at Jupiter in July 2016 and orbit its poles 33 times to find out more about the gas giant's interior, atmosphere and aurora. Scientists believe Jupiter holds the key to better understanding the origins of our solar system.

Video credit: NASA

Juno on the Launch Pad

NASA's Juno spacecraft awaits launch from inside the payload fairing atop a United Launch Alliance Atlas V-551 launch vehicle. Juno and its rocket are at Space Launch Complex 41 on Cape Canaveral Air Force Station in Florida.

Photo credit: NASA/Kennedy Space Center

Amateurs to Take a Crack at Juno Images

Data from the camera onboard NASA's Juno mission, called JunoCam, will be made available to the public for processing into their own images. An example of this type of collaboration is illustrated here with an image of Jupiter taken by NASA's Voyager mission, and processed by Björn Jónsson. The image highlights Jupiter's "Great Red Spot."

Photo credit: NASA/JPL-Caltech

Juno Being Lowered into Position

At Space Launch Complex 41, the Juno spacecraft, enclosed in an Atlas payload fairing, was transferred into the Vertical Integration Facility where it was positioned on top of the Atlas rocket stacked inside.

Photo credit: NASA/Kennedy Space Center

Juno's Solar Array

In this image technicians stow for launch solar array #2 for NASA's Juno spacecraft. The photo was taken on May 20, 2011 at the Astrotech payload processing facility in Titusville, Florida. NASA's Juno spacecraft is scheduled to launch aboard an Atlas V rocket from Cape Canaveral, Florida. August 5. The solar-powered spacecraft will orbit Jupiter's poles 33 times to find out more about the gas giant's origins, structure, atmosphere and magnetosphere and investigate the existence of a solid planetary core.

Photo credit: NASA/JPL-Caltech/KSC

Acetylene at Jupiter's North and South Poles

These images and movie show the distribution of the organic molecule acetylene at the north and south poles of Jupiter, based on data obtained by NASA's Cassini spacecraft in early January 2001. It is the highest-resolution map of acetylene to date on Jupiter. The enhanced emission results both from the warmer temperatures in the auroral hot spots, and probably also from an enhanced abundance in these regions. The detection helps scientists understand the chemical interactions between sunlight and molecules in Jupiter's stratosphere.

These maps were made by NASA's composite infrared spectrometer.

Photo and video credit: NASA/JPL/GSFC

Jupiter Loses a Stripe

In a development that has transformed the appearance of the solar system's largest planet, one of Jupiter's two main cloud belts has completely disappeared.

"This is a big event," says planetary scientist Glenn Orton of NASA's Jet Propulsion Lab. "We're monitoring the situation closely and do not yet fully understand what's going on."

Known as the South Equatorial Belt (SEB), the brown cloudy band is twice as wide as Earth and more than twenty times as long. The loss of such an enormous "stripe" can be seen with ease halfway across the solar system.

...

Orton thinks the belt is not actually gone, but may be just hiding underneath some higher clouds.

"It's possible," he hypothesizes, "that some 'ammonia cirrus' has formed on top of the SEB, hiding the SEB from view." On Earth, white wispy cirrus clouds are made of ice crystals. On Jupiter, the same sort of clouds can form, but the crystals are made of ammonia (NH3) instead of water (H20).

What would trigger such a broad outbreak of "ammonia cirrus"? Orton suspects that changes in global wind patterns have brought ammonia-rich material into the clear, cold zone above the SEB, setting the stage for formation of the high-altitude, icy clouds.

...

This isn't the first time the SEB has faded out.

"The SEB fades at irregular intervals, most recently in 1973-75, 1989-90, 1993, 2007, 2010," says John Rogers, director of the British Astronomical Association's Jupiter Section. "The 2007 fading was terminated rather early, but in the other years the SEB was almost absent, as at present."

The return of the SEB can be dramatic.

"We can look forward to a spectacular outburst of storms and vortices when the 'SEB Revival' begins," says Rogers. "It always begins at a single point, and a disturbance spreads out rapidly around the planet from there, often becoming spectacular even for amateurs eyeballing the planet through medium-sized telescopes. However we can't predict when or where it will start. On historical precedent it could be any time in the next 2 years. We hope it will be in the next few months so that everyone can get a good view.

Photo credit: Anthony Wesley

Jupiter and Io, by New Horizons

This is a montage of New Horizons images of Jupiter and its volcanic moon Io, taken during the spacecraft’s Jupiter flyby [pdf] in early 2007. The Jupiter image is an infrared color composite taken by the spacecraft’s near-infrared imaging spectrometer, the Linear Etalon Imaging Spectral Array (LEISA) at 1:40 UT on February 28, 2007. The infrared wavelengths used (red: 1.59 µm, green: 1.94 µm, blue: 1.85 µm) highlight variations in the altitude of the Jovian cloud tops, with blue denoting high-altitude clouds and hazes, and red indicating deeper clouds. The prominent bluish-white oval is the Great Red Spot. The observation was made at a solar phase angle of 75 degrees but has been projected onto a crescent to remove distortion caused by Jupiter’s rotation during the scan. The Io image, taken at 00:25 UT on March 1st 2007, is an approximately true-color composite taken by the panchromatic Long-Range Reconnaissance Imager (LORRI), with color information provided by the 0.5 µm (“blue”) and 0.9 µm (“methane”) channels of the Multispectral Visible Imaging Camera (MVIC). The image shows a major eruption in progress on Io’s night side, at the northern volcano Tvashtar. Incandescent lava glows red beneath a 330-kilometer high volcanic plume, whose uppermost portions are illuminated by sunlight. The plume appears blue due to scattering of light by small particles in the plume.

Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute

Juno

Launching from Earth in 2011, the Juno spacecraft will arrive at Jupiter in 2016 to study the giant planet from an elliptical, polar orbit. Juno will repeatedly dive between the planet and its intense belts of charged particle radiation, coming only 5,000 kilometers (about 3,000 miles) from the cloud tops at closest approach.

Juno's primary goal is to improve our understanding of Jupiter's formation and evolution. The spacecraft will spend a year investigating the planet's origins, interior structure, deep atmosphere and magnetosphere. Juno's study of Jupiter will help us to understand the history of our own solar system and provide new insight into how planetary systems form and develop in our galaxy and beyond.

Illustration credit: NASA/JPL