Juno Mission Update 10/17/13

 

Elapsed Mission Time:
02 years 074 Days 10 Hours 01 Minutes

Arrival at Jupiter:
02 Years 262 Days 00 Hours 02 Minutes

 

Since the government shutdown NASA has been shut down.  I am happy to report they have come back on-line as the hardheads in congress have finally come to an agreement.  So only a small amount of what has been going with Juno has gotten out to the public-they had to have someone on watch somewhere !  But they also had to be few and far between maybe even voluntary.  Anyway I will update you about what has been going on:

Juno's position to Earth on Sept 16, 2013

Juno’s Earth flyby gravity assist was completed on Oct. 9th (not the 12th for unknown reasons) Navigation has confirmed that Juno's current trajectory is "near-perfect" vs. planned. Several Juno science instruments made planned observations during the approach to Earth, including the Advanced Stellar Compass, JunoCam and Waves. These observations provided a useful opportunity to test the instruments during a close planetary encounter and ensure that they work as designed. The main goal of the flyby – to give the spacecraft the boost it needed in order to reach Jupiter – was accomplished successfully, and the spacecraft is healthy and operating as expected.

This  image was taken  when the spacecraft was close to the Earth. It is also taken through Juno Cam's methane filter. In this one we can see the southernmost tip of South America and a little bit of the Antarctic.

Soon after its closest approach to Earth, the spacecraft initiated the first of two "safe modes" that have occurred since the flyby. Safe mode is a state that the spacecraft may enter if its on-board computer perceives conditions on the spacecraft are not as expected. Onboard Juno, the safe mode turned off instruments and a few non-critical spacecraft components, and pointed the spacecraft toward the sun to ensure the solar arrays received power. The likely cause of the safe mode was an incorrect setting for a fault protection trigger for the spacecraft's battery. During the eclipse the solar cells, as expected, were not generating electricity and the spacecraft was drawing on the battery supply. When the voltage dropped below this fault protection trigger, the spacecraft initiated the safe mode sequence. The spacecraft acted as expected during the transition into and while in safe mode. The spacecraft exited the safe mode on Oct. 11.

Flyby Photo of Juno: Earth dayside  Time: 12:03:30 PDT Exposure: 0.2 milliseconds Time delay integration: 1

The first color reconstruction of the Moon.

The spacecraft entered the safe mode configuration again on Sunday evening (10/13/13). When the spacecraft's onboard computer transitioned from the Earth flyby sequence to the cruise sequence, a component called the stellar reference unit remained in the Earth flyby configuration. When the spacecraft's computer saw the draw on electricity was slightly greater than expected, it did as it was programmed to do and initiated a safe mode event. The mission team is in two-way communications with the spacecraft and it is operating as expected, and designed for, in safe mode. They expect to exit safe mode sometime next week.  With the Earth flyby completed, Juno is now on course for arrival at Jupiter on July 4, 2016.

Juno's Position to Earth October 17, 2013

As of Oct. 17, Juno was approximately 4.4 million miles (7.1 million kilometers) from Earth. The one-way radio signal travel time between Earth and Juno is currently about 24 seconds. Juno is currently traveling at a velocity of about 23.6 miles (38 kilometers) per second relative to the sun. Velocity relative to Earth is about 6.5 miles (10.4 kilometers) per second. Juno has now traveled 1.01 billion miles (1.63 billion kilometers, or 10.9 AU) since launch.

Juno is now halfway to Jupiter !!!

Juno Mission Update 9/26/13

 

 

Elapsed Mission Time:

02 Years 53 days (1.75 months) 06 Hours 43 Minutes

To Earth Flyby:

12 Days 20 Hours 13 Minutes

To Jupiter Arrival:

02 Years 283 Days (9.93 months) 03 Hours 20 Minutes

 

NASA's Juno spacecraft successfully executed a second Deep Space Maneuver, called DSM-2 on Friday, Sept. 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 Oct 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's Current Position

As of Sept. 16, Juno was approximately 13 million miles (21 million kilometers) from Earth. The one-way radio signal travel time between Earth and Juno is currently about 71 seconds. Juno is currently traveling at a velocity of about 23 miles (37 kilometers) per second relative to the sun. Velocity relative to Earth is about 7 miles (11 kilometers) per second. Juno has now traveled 951 million miles (1.53 billion kilometers, or 10.1 AU) since launch.  The Juno spacecraft is in excellent health and is operating nominally. All science instruments are powered off except for the magnetometer experiment, which continues to operate in low-power mode.

 

Artist’s rendering of the Juno spacecraft approaching Earth on Oct. 9, 2013.

NASA’s Jupiter-bound Juno spacecraft will perform a close flyby of Earth on Oct. 9, 2013. The time of closest approach is approximately 19:21 UTC (3:21 pm U.S. Eastern time). During the flyby Juno will come to within 347 miles (559 kilometers) of Earth.  Juno will receive a huge boost from Earth’s gravity equivalent to about 70 percent of the total change in velocity, or delta-v, provided by the Atlas V 551 rocket. The boost from the flyby is almost as powerful as a second rocket launch. The spacecraft passes over South Africa at the point of closest approach. Shortly after this point, Juno will pass into Earth’s shadow for about 20 minutes. Juno emerges from the planet’s shadow when it is about 5,400 miles (8,700 kilometers) above Earth at approximately 19:39 UTC when it is over the east coast of India.

 

Map showing Juno’s ground track during the Earth flyby.

• Plans for the close flyby:
  The close flyby provides the opportunity for a trial run of science operations at Jupiter. The Juno team will use this occasion to exercise Juno’s science instruments and sample a planetary magnetosphere to get a preview of what to expect from the spacecraft once it arrives at the giant planet. Most of Juno’s science instruments have observations planned for the encounter, except for the exquisitely sensitive Microwave Radiometer, which will remain powered off as a protective measure. 
  
• Juno’s imaging camera for public engagement, called JunoCam, will take a series of color images of our home planet beginning near the time of closest approach.
  
• The radio and plasma wave instrument, called Waves, will listen to the transmissions of Earth’s magnetosphere – possibly detecting signals of human origin as well.
  
• Once processing of these data products is completed, these visuals will be published.

Juno Mission Update 6/29/13

 

 

Mission Elapsed Time:
694 Days (1.91 years) 10 Hours 17 Minutes

Time to Earth Flyby Gravity Assist:
101 Days (3.4 months)16 Hours 45 Minutes

Time of Jupiter Arrival:
3 years 6 days 23 Hours 50 Minutes

 

As of June 21, Juno was approximately 50 million miles (80 million kilometers) from Earth. The one-way radio signal travel time between Earth and Juno is currently about 4.5 minutes. Juno is currently traveling at a velocity of about 19 miles (30 kilometers) per second relative to the sun, and increasing. Velocity relative to Earth is about 1.6 miles (2.6 kilometers) per second. Juno has now traveled 785 million miles (1.26 billion kilometers) since launch.  The Juno spacecraft is in excellent health and is operating nominally as it cruises toward its Oct. 9 Earth flyby gravity assist maneuver.

 

Juno’s Position and Course 6/29/13

Recent spacecraft significant events:

As of May 29, Juno has entered the phase of its mission titled "Inner Cruise 3," in which it has switched from its high-data-rate High Gain Antenna to its suite of lower data rate antennas. The magnetometer experiment remains powered on at low data rates, with all other science instruments currently powered off. Inner Cruise 3 lasts through Nov. 2013 and includes the Earth flyby.

 

Juno's Communications Antennas:  The Juno spacecraft has five antennas, including the largest and primary communication antenna, known as the high-gain antenna (HGA). Four other antennas can be used as backups, or when the main antenna is pointed away from Earth, for certain science operations and navigation maneuvers.

The solar-powered Juno spacecraft and its saucer-shaped high-gain antenna (or HGA) always point sunward, but while Juno is in the inner solar system, Earth’s position on the sky shifts dramatically. Earth’s movement means that Juno cannot always use its HGA and benefit from its high data rate connection. For this reason, the spacecraft has a suite of antennas that allow communications with Earth from other angles, but at the cost of lower data rates, resulting in a reduction in Juno’s ability to transmit science data during that time. Juno’s science instruments will be powered on again shortly before the Earth flyby, slated for Oct. 9.

 

Juno’s Main Engine Covered

Juno’s mission ops team performed a flush of the spacecraft’s main engine on May 1, firing the engine for a couple of seconds. The team does this maintenance activity about once per year to flush contaminants from the propellant lines that feed the main engine.

Juno Mission Update 4/29/13

Mission Elapsed Time:
633 Days (1.73 yrs.) 10 Hours 45 Minutes

Time to Earth Flyby Gravity Assist:
162 Days 16 Hours 11 Minutes

Time to Jupiter Arrival:
3 Years 67 Days 23 Hours 16 Minutes

 

As of April 29, Juno was approximately 52 million miles (84 million kilometers) from Earth. The one-way radio signal travel time between Earth and Juno is currently about 4.7 minutes. Juno is currently traveling at a velocity of about 15 miles (24 kilometers) per second relative to the sun. Velocity relative to Earth is about 6.8 miles (11 kilometers) per second.

 

Juno's Course and Position as of 4/29/13

 

Juno has now traveled 704 million miles since launch -- this is approximately 40 percent of the total distance the spacecraft travels between launch and orbit insertion at Jupiter. The Juno spacecraft is in excellent health and is operating nominally. Four instruments -- JEDI, MWR, Waves, and MAG -- are turned on.  Juno is currently headed back toward the inner solar system for a planned Earth flyby gravity assist maneuver on Oct. 9, 2013. The Juno mission operations team is continuing their planning activities in advance of this critical maneuver. The gravity assist will give the spacecraft the boost it needs to reach Jupiter, where it is slated to arrive in July 2016.
 

 

 

 

 

 

 

 

A high resolution image of Jupiter's clouds taken by NASA's Voyager 1 spacecraft as it flew past the planet in March 1979.

 

Artist's rendering of a Jupiter cloudscape.

 

Jupiter's clouds can swirl rapidly in raised high-pressure storm systems that circle the planet. The above pictured white ovals are located near the Great Red Spot, and have persisted on Jupiter since the 1930s. The Great Red Spot has persisted for at least 300 years. Currently, no one knows why ovals last as long as they do. White ovals are confined to circular belts around Jupiter, but can interact to cause nearby chaotic cloud regions.

 

Diagram showing theoretical conditions, temperatures, and pressures in Jupiter's interior.

 

Juno Mission Update 3/15/13

 

Mission Elapsed Time:

 

  588 Days (1.61 yrs.) 09 Hours 30 MinuteS

 

Time to Earth Flyby Gravity Assist:

207 Days (.57 yrs.) 17 Hours 27 Minutes

 

Time To Jupiter Arrival:

 

03 Years 111 Days 01 Hours 35 Minutes

 

As of March 8, Juno is approximately 92 million miles (147 million kilometers) from Earth, with a one-way radio signal travel time of 8.2 minutes. Juno is currently traveling at a velocity of 12.6 miles (20.2 kilometers) per second relative to the sun. Velocity relative to Earth is 13.9 miles (22.4 kilometers) per second.

 

Juno's Present Course and Position

The Juno spacecraft is in excellent health and is operating nominally. Four instruments -- JEDI, MAG, MWR and Waves -- are turned on.

 

'Hot Spots' Ride a Merry-Go-Round on Jupiter:

 

This false-color image from Cassini is a window deep into Jupiter's atmosphere. The arrow points to the dark hot spot. The bluish clouds to the right are in the upper troposphere, or perhaps higher still, in the stratosphere. The reddish gyre under the hot spot to the right and the large reddish plume at its lower left are in the lower troposphere.

In the swirling canopy of Jupiter's atmosphere, cloudless patches are so exceptional that the big ones get the special name "hot spots." Exactly how these clearings form and why they're only found near the planet’s equator have long been mysteries. Now, using images from NASA's Cassini spacecraft, scientists have found new evidence that hot spots in Jupiter's atmosphere are created by a Rossby wave, a pattern also seen in Earth's atmosphere and oceans. The team found the wave responsible for the hot spots glides up and down through layers of the atmosphere like a carousel horse on a merry-go-round.  Rossby waves are atmospheric waves (can be seen in the troughs and ridges of 500 hPa geopotential caused by midlatitude cyclones and anticyclones). The hPa or hecotoPascal is the SI derived unit of pressure, internal pressure, or stress in the atmosphere. It is a measure of force per unit area, defined as one newton per square meter. Rossby waves have been suggested as an important mechanism to account for the heating of Europa's ocean.

 

NASA postdoctoral fellow David Choi discusses his study of dark features in Jupiter's atmosphere called "hot spots," and their connection to large-scale atmospheric waves.

This is the first time anybody has closely tracked the shape of multiple hot spots over a period of time, which is the best way to appreciate the dynamic nature of these features," said the study's lead author, David Choi, a NASA Postdoctoral Fellow working at NASA's Goddard Space Flight Center in Greenbelt, Md.  The paper was published online in the April issue of the journal Icarus.  Choi and his colleagues made time-lapse movies from hundreds of observations taken by Cassini during its flyby of Jupiter in late 2000, when the spacecraft made its closest approach to the planet. The movies zoom in on a line of hot spots between one of Jupiter's dark belts and bright white zones, roughly 7 degrees north of the equator. Covering about two months (in Earth time), the study examines the daily and weekly changes in the sizes and shapes of the hot spots, each of which covers more area than North America, on average.

 

In this series of images from Cassini, a dark, rectangular hot spot (top) interacts with a line of vortices that approaches from on the upper-right side (second panel). The interaction distorts the shape of the hot spot (third panel), leaving it diminished (bottom).

Much of what scientists know about hot spots came from NASA's Galileo mission, which released an atmospheric probe that descended into a hot spot in 1995. This was the first, and so far only, in-situ investigation of Jupiter's atmosphere.  Galileo's probe data and a handful of orbiter images hinted at the complex winds swirling around and through these hot spots, raised questions about whether they fundamentally were waves, cyclones or something in between," said Ashwin Vasavada, a paper co-author who is based at NASA's Jet Propulsion Laboratory in Pasadena, Calif., and who was a member of the Cassini imaging team during the Jupiter flyby. "Cassini's fantastic movies now show the entire life cycle and evolution of hot spots in great detail.

 

Infrared image of Jupiter taken by the ESO's Very Large Telescope.

Because hot spots are breaks in the clouds, they provide windows into a normally unseen layer of Jupiter's atmosphere, possibly all the way down to the level where water clouds can form. In pictures, hot spots appear shadowy, but because the deeper layers are warmer, hot spots are very bright at the infrared wavelengths where heat is sensed; in fact, this is how they got their name.  One hypothesis is that hot spots occur when big drafts of air sink in the atmosphere and get heated or dried out in the process. But the surprising regularity of hot spots has led some researchers to suspect there is an atmospheric wave involved. Typically, eight to 10 hot spots line up, roughly evenly spaced, with dense white plumes of cloud in between. This pattern could be explained by a wave that pushes cold air down, breaking up any clouds, and then carries warm air up, causing the heavy cloud cover seen in the plumes. Computer modeling has strengthened this line of reasoning.

From the Cassini movies, the researchers mapped the winds in and around each hot spot and plume, and examined interactions with vortices that pass by, in addition to wind gyres, or spiraling vortices, that merge with the hot spots. To separate these motions from the jet stream in which the hot spots reside, the scientists also tracked the movements of small "scooter" clouds, similar to cirrus clouds on Earth. This provided what may be the first direct measurement of the true wind speed of the jet stream, which was clocked at about 300 to 450 mph (500 to 720 kilometers per hour) -- much faster than anyone previously thought. The hot spots amble at the more leisurely pace of about 225 mph (362 kilometers per hour).  By teasing out these individual movements, the researchers saw that the motions of the hot spots fit the pattern of a Rossby wave in the atmosphere. On Earth, Rossby waves play a major role in weather. For example, when a blast of frigid Arctic air suddenly dips down and freezes Florida's crops, a Rossby wave is interacting with the polar jet stream and sending it off its typical course. The wave travels around our planet but periodically wanders north and south as it goes.

Juno Mission Update 1/21/13

 

Elapsed Mission Time:
534 Days (1.46 yrs.) 12  Hours 56 Minutes

Time Until Earth Flyby Gravity Assist:
261 Days (.72 yrs.) 02 Hours 01 Minutes

 

As of Jan. 20, Juno was approximately 160 million miles (257 million kilometers) from Earth, with a one-way radio signal travel time of approximately 14 minutes. Juno is currently traveling at a velocity of 11 miles (18 kilometers) per second relative to the sun. Velocity relative to Earth is 20 miles (32 kilometers) per second.

 

Juno's Course and Position 1/20/13

 

The Juno spacecraft is in excellent health and is operating nominally. Four instruments -- JEDI, MWR, Waves, and MAG -- are turned on.  Juno is currently headed back toward the inner solar system for a planned Earth flyby gravity assist maneuver on Oct. 9, 2013. The gravity assist will give the spacecraft the boost it needs to reach Jupiter, where it is slated to arrive in July 2016.

 

 

Juno Mission Overview Update: