Monday, February 17, 2014

Juno Mission Update 2/17/14

 

Juno fires its main engine

Juno Mission Elapsed Time:
2 Years 196 Days 09 Hours 59 Minutes

Time Until Arrival at Jupiter:
2 Years 140 Days 00 Hours 05 Minutes

This is one mission that is going slow right now.  What I am reporting has taken place that many people may not know completely about.  I didn’t until I looked into the matter.  This mission’s sites are different from that of any of the other missions I have covered or am covering now.

 

Juno won't get near no icy moons of Jupiter.  But there is a fascinating video that just came out of Ganymede Jupiter's largest moon:

Ganymede the Largest Solar System Moon Detailed in a Geologic Map

Animation of a rotating globe of Jupiter's moon Ganymede, with a geologic map superimposed over a global color mosaic. The 37-second animation begins as a global color mosaic image of the moon then quickly fades in the geologic map.  More than 400 years after its discovery by astronomer Galileo Galilei, the largest moon in the solar system – Jupiter's moon Ganymede – has finally claimed a spot on the map. A group of scientists led by Geoffrey Collins of Wheaton College has produced the first global geologic map of Ganymede, Jupiter’s seventh moon. The map combines the best images obtained during flybys conducted by NASA's Voyager 1 and 2 spacecraft (1979) and Galileo orbiter (1995 to 2003) and is now published by the U. S. Geological Survey as a global map. It technically illustrates the varied geologic character of Ganymede’s surface and is the first global, geologic map of this icy, outer-planet moon.  It is a shame but Juno will not be looking at many of Jupiter’s moons.

 

12/10/13  JUNO GIVES STARSHIP-LIKE VIEW OF EARTH FLYBY:

 

Results from Juno's October Earth flyby, shared today at the American Geophysical Union fall meeting, include a unique approach movie and a message sent by amateur radio operators.

Juno Earth Fly –by

When NASA’s Juno spacecraft flew past Earth on Oct. 9, 2013, it received a boost in speed of more than 8,800 mph (about 7.3 kilometer per second), which set it on course for a July 4, 2016, rendezvous with Jupiter, the largest planet in our solar system. One of Juno's sensors, a special kind of camera optimized to track faint stars, also had a unique view of the Earth-moon system. The result was an intriguing, low-resolution glimpse of what our world would look like to a visitor from afar. "If Captain Kirk of the USS Enterprise said, ‘Take us home, Scotty,’ this is what the crew would see," said Scott Bolton, Juno principal investigator at the Southwest Research Institute, San Antonio. “In the movie, you ride aboard Juno as it approaches Earth and then soars off into the blackness of space. No previous view of our world has ever captured the heavenly waltz of Earth and moon."

 

Also during the flyby, Juno's Waves instrument, which is tasked with measuring radio and plasma waves in Jupiter's magnetosphere, recorded amateur radio signals. This was part of a public outreach effort involving ham radio operators from around the world. They were invited to say "HI" to Juno by coordinating radio transmissions that carried the same Morse-coded message. Operators from every continent, including Antarctica, participated.

 

Radio Wave Signal fly-by

During its close flyby of Earth, NASA's Jupiter-bound Juno spacecraft listened for a coordinated, global transmission from amateur radio operators using its radio and plasma wave science instrument, known as Waves. This spectrogram and audio file illustrate that Waves did indeed detect the message.  The video presents natural radio signals from Earth's magnetosphere along with pieces of the repeated Morse code message, recorded by Juno and turned into sound.  In Morse code, characters are formed using dots and dashes, or "dits and dahs." The word "HI" is formed by transmitting four dits for "H," followed by a space and then two more dits for "I." The full message was transmitted 16 times, beginning again every 10 minutes, starting at 18:00 UTC (2 p.m. Eastern time) on Oct. 9, 2013. Each dit lasted 30 seconds. Radio operators used two webpages (provided by NASA's Jet Propulsion Laboratory and the Juno team) to synchronize their transmissions.  The green dots at top represent pieces of the repeated message that Juno was able to detect. Grey dots represent parts of the message that were being transmitted, but which were not clearly detected by the Waves instrument. Scientists have processed the data to identify the ham radio signal and to isolate it from the natural background. The strength of the ham radio signals is not indicated here, merely their detection in the data.  More than 1,400 radio operators from around the world confirmed their participation in the activity. Given the variable conditions in Earth's ionosphere and uncertainties in how many hams would participate, scientists on the Waves team were not sure all the signals could be detected. They were ecstatic when the message could be readily seen in the data. 

INSTRUMENT (JEDI)  JUNO ENERGETIC PARTICLE DETECTOR INSTRUMENT (JEDI):

The Jupiter Energetic Particle Detector Instrument (JEDI) will measure the energetic particles that stream through space, and study how they interact with Jupiter’s magnetic field.  Jupiter's radiation belts are very strong and dangerous and could pose a hazard to Juno and future missions to Jupiter.  So NASA’s study of them are extremely important.


Jupiter Energetic Particle Detector Instrument (JEDI) Barry Mauk explains that measuring high-energy particles with JEDI will help us understand how the energy of Jupiter's rotation is being funneled into its magnetosphere and atmosphere. As of Jan. 10, Juno was approximately 125 million kilometers from Earth. The one-way radio signal travel time between Earth and Juno is currently about seven minutes. Juno is currently traveling at a velocity of about 28 kilometers per second relative to the sun. Velocity relative to Earth is about 26 kilometers per second. Juno has now traveled 1.87 billion kilometers, or 12.5 AU since launch.

 

juno solar array

One of  Juno's Solar Array Panels

On 1/26/14: The Juno spacecraft is in excellent health and is operating nominally. The Juno operations team successfully enabled the solar array medium strings (for the second and final time) on Jan. 7. This action increases available power, adding three medium string panels to the two long string panels, as the spacecraft moves farther outward from the sun and into the asteroid belt. The next (and final) string enable will be to bring the six short-string panels online around Sept. 2014. With that action, the full power production capability of Juno's huge solar arrays -- the first to power a mission to Jupiter -- will be enabled

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