Following the speed boosting slingshot of Earth on Wednesday, Oct. 9, that sent NASA’s Juno orbiter hurtling towards Jupiter, the probe has successfully transmitted back data and the very first flyby images despite unexpectedly going into ‘safe mode’ during the critical maneuver.
“Juno is transmitting telemetry today,” spokesman Guy Webster, of NASA’s Jet Propulsion Lab (JPL), told me in a phone interview late today (Oct. 10), as Juno continues sailing on its 2.8 Billion kilometer (1.7 Billion mile) outbound trek to the Jovian system.
The new images of Earth captured by the Junocam imager serves as tangible proof that Juno is communicating.
“Juno is still in safe mode today (Oct. 10),” Webster told Universe Today.
“Teams at mission control at JPL and Lockheed Martin are actively working to bring Juno out of safe mode. And that could still require a few days,” Webster explained.
Lockheed Martin is the prime contractor for Juno.
The initial raw images of Earth snapped by the craft’s Junocam imager were received by ground stations late today.
See above a day light image mosaic which I reconstructed and realigned based on the original raw image (see below) taken with the camera’s methane filter on Oct. 9 at 12:06:30 PDT (3:06:30 PM EST). Juno was to be flying over South America and the southern Atlantic Ocean.
Juno performed a crucial swingby of Earth on Wednesday that accelerated the probe by 16330 MPH to enable it to arrive in orbit around Jupiter on July 4, 2016.
However the gravity assist maneuver did not go entirely as planned.
Shortly after Wednesday’s flyby, Juno Project manager Rick Nybakken, of JPL, told me in a phone interview that Juno had entered safe mode but that the probe was “power positive and we have full command ability.”
“After Juno passed the period of Earth flyby closest approach at 12:21 PM PST [3:21 PM EDT] and we established communications 25 minutes later, we were in safe mode,” Nybakken explained.
The safe mode was triggered while Juno was in an eclipse mode, the only eclipse it will experience during its entire mission.
The Earth flyby did accomplish its objective by placing the $1.1 Billion Juno spacecraft exactly on course for Jupiter as intended.
“We are on our way to Jupiter as planned!”
“None of this affected our trajectory or the gravity assist maneuver – which is what the Earth flyby is,” Nybakken stated.
Juno’s closest approach was over South Africa at about 561 kilometers (349 miles).
During the flyby, the science team also planned to observe Earth using most of Juno’s nine science instruments since the slingshot also serves as a key test of the spacecraft systems and the flight operations teams.
Juno also was to capture an unprecedented new movie of the Earth/Moon system.
Many more images were snapped and should be transmitted in coming days that eventually will show a beautiful view of the Earth and Moon from space.
“During the earth flyby we have most of our instruments on and will obtain a unique movie of the Earth Moon system on our approach, Juno principal investigator Scott Bolton told me. Bolton is from the Southwest Research Institute (SwRI), San Antonio, Texas.
“We will also calibrate instuments and measure earth’s magnetosphere, obtain closeup images of the Earth and the Moon in UV [ultraviolet] and IR [infrared],” Bolton explained to Universe Today.
Juno is approaching the Earth from deep space, from the sunlit side.
“Juno will take never-before-seen images of the Earth-moon system, giving us a chance to see what we look like from Mars or Jupiter’” says Bolton.
Here is a description of Junocam from the developer – Malin Space Science Systems
“Like previous MSSS cameras (e.g., Mars Reconnaissance Orbiter’s Mars Color Imager) Junocam is a “pushframe” imager. The detector has multiple filter strips, each with a different bandpass, bonded directly to its photoactive surface. Each strip extends the entire width of the detector, but only a fraction of its height; Junocam’s filter strips are 1600 pixels wide and about 155 rows high. The filter strips are scanned across the target by spacecraft rotation. At the nominal spin rate of 2 RPM, frames are acquired about every 400 milliseconds. Junocam has four filters: three visible (red/green/blue) and a narrowband “methane” filter centered at about 890 nm.”
During a one year long science mission – entailing 33 orbits lasting 11 days each – the probe will plunge to within about 3000 miles of the turbulent cloud tops and collect unprecedented new data that will unveil the hidden inner secrets of Jupiter’s origin and evolution.
NBC News has also featured this Juno story – here
Read more about Juno’s flyby in my articles – here and here
Stay tuned here for continuing Juno, LADEE, MAVEN and more up-to-date NASA news.