Mission Elapsed Time: 439 Days (1.20 yrs.) 11 Hours 25 Minutes
Time of Arrival: 1355 Days ( 3.71 yrs.) 22 Hours 35 Minutes
Juno is approximately 282 million miles (452 million kilometers) from Earth, with a one-way radio signal travel time of approximately 25 minutes. The spacecraft has now traveled 512 million miles (824 million kilometers) since launch, which is nearly 27 percent of its total cruise distance to Jupiter. Juno is currently traveling at a velocity of 33,600 miles (54,000 kilometers) per hour relative to the sun. Velocity relative to Earth is 94,900 miles (152,600 kilometers) per hour.
Juno’s Current Position and Course
The Juno spacecraft is in excellent health and is operating nominally. Four instruments -- JEDI, MWR, Waves, and the magnetometer experiment -- are turned on. Juno’s mission operations team is currently focused on periodic maintenance activities for the science instruments, turning on each one for a few days at a time to monitor its health and performance. Juno is currently headed back toward the inner solar system for a planned Earth flyby gravity assist maneuver on Oct. 9, 2013. The spacecraft completed a trajectory control maneuver (TCM-5) using its reaction control thrusters on Oct. 3, for the fifth time further refining its path toward Earth. Juno was not designed to study the Jovian moons, but may take a few distant images. More detailed info in the future on this subject.
New results from NASA's Wide-field Infrared Explorer, or WISE, reveal that the Jovian Trojans -- asteroids that lap the sun in the same orbit as Jupiter -- are uniformly dark with a hint of burgundy color, and have matte surfaces that reflect little sunlight. The color could indicate heavy concentration of the element Iron.
Scientists using data from NASA's Wide-field Infrared Survey Explorer, or WISE, have uncovered new clues in the ongoing mystery of the Jovian Trojans -- asteroids that orbit the sun on the same path as Jupiter. Like racehorses, the asteroids travel in packs, with one group leading the way in front of the gas giant, and a second group trailing behind. The observations are the first to get a detailed look at the Trojans' colors: both the leading and trailing packs are made up of predominantly dark, reddish rocks with a matte, non-reflecting surface. What's more, the data verify the previous suspicion that the leading pack of Trojans outnumbers the trailing bunch.
The new results offer clues in the puzzle of the asteroids' origins. Where did the Trojans come from? What are they made of? WISE has shown that the two packs of rocks are strikingly similar and do not harbor any "out-of-towners," or interlopers, from other parts of the solar system. The Trojans do not resemble the asteroids from the main belt between Mars and Jupiter, nor the Kuiper belt family of objects from the icier, outer regions near Pluto.
"Jupiter and Saturn are in calm, stable orbits today, but in their past, they rumbled around and disrupted any asteroids that were in orbit with these planets," said Tommy Grav, a WISE scientist from the Planetary Science Institute in Tucson, Ariz. "Later, Jupiter re-captured the Trojan asteroids, but we don't know where they came from. Our results suggest they may have been captured locally. If so, that's exciting because it means these asteroids could be made of primordial material from this particular part of the solar system, something we don't know much about." Grav is a member of the NEOWISE team, the asteroid-hunting portion of the WISE mission.
Astronomer Max Wolf
The first Trojan was discovered on Feb. 22, 1906, by German astronomer Max Wolf, who found the celestial object leading ahead of Jupiter. Christened "Achilles" by the astronomer, the roughly 81-mile-wide (130-kilometer-wide) chunk of space rock was the first of many asteroids detected to be traveling in front of the gas giant. Later, asteroids were also found trailing behind Jupiter. The asteroids were collectively named Trojans after a legend, in which Greek soldiers hid inside in a giant horse statue to launch a surprise attack on the Trojan people of the city of Troy.
NASA's Wide-field Infrared Survey Explorer, or WISE, spacecraft is situated on a work stand. At left on the spacecraft is the fixed panel solar array. In front, the square is the HGA Slotted Array (Ku-Band).
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