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Home https://server7.kproxy.com/servlet/redirect.srv/sruj/smyrwpoii/p2/ Juno fears the death of Shadow Jupiter. So he started his engine for over 10 hours to avoid it.

Juno fears the death of Shadow Jupiter. So he started his engine for over 10 hours to avoid it.



In a maneuver that causes death for the spacecraft, NASA's June did an unprecedented and unplanned engine burn. Target? To save the life of the spacecraft or at least the rest of its mission to Jupiter.

Jupiter casts a deep dark shadow. In fact, it's dark enough to effectively kill Juno if she flies through it. Instead of allowing the spacecraft to spend 12 hours recharging the battery in the shadow of Jupiter and then attempting to risk resuscitation on the other hand, NASA took a different course of action: a 10.5-hour burn of Juno's propulsion that would save him from Jupiter's life – a torrential shadow .

10.5 hours is a very long burn and it consumes about 73 kg (1

60 lbs) of fuel. But without doing so, Juno would have plunged into the deep dark shadow of Jupiter on November 3, following his close approach to the gas giant. It's been 12 hours in the shade, long enough to fully charge the batteries. The spacecraft's temperature would drop, and without the energy in the batteries, it would most likely succumb to cold, never to wake up again.

This animated gift depicts the perspective of NASA's Juno spacecraft as it approaches the eclipse of the gas giant on November 3, 2019. The sun is depicted as a yellow dot rising to the left of the planet. Image Credit: NASA / JPL-Caltech / SWRI

Fortunately, the burn was successful, and according to investigator Juon Scott Bolton, it was an "amazingly creative solution" to Jupiter's shadow problem.

"With the success of this tutelage, we are on the path to jumping the shadow of November 3," said Scott Bolton, Juno's chief investigator at the Southwestern San Antonio Research Institute. "Jumping through the shadows was an extremely creative solution to what seemed like fatal geometry. Eclipses are usually not friends of solar-powered spaceships. Now, instead of worrying about freezing to death, I look forward to the next discovery of the science that Jupiter has in store for Juno. "

This shadow-evading burnout emphasizes how common Juno's orbit is to the general.

Juno has been on Jupiter since July 2016. Since that time, he has performed a number of long elliptical orbits. Darkness is not the only thing that Juno The intense radiation of Jupiter means that the spacecraft is stepping very carefully around the planet, each pole orbit bringing it to the bands of intense radiation that surround Jupiter, where the spacecraft dives below the belts to make the best science. Juno around o Jupiter will be very elliptical because it contradicts Jupiter's powerful radiation belts Image: NASA / JPL ” class=”wp-image-129665″ srcset=”https://www.universetoday.com/wp-content/uploads/2016/06/Juno_trajectory_through_radiation_belts.png 612w, https://www.universetoday.com/wp-content/uploads/2016/06/Juno_trajectory_through_radiation_belts-250×172.png 250w, https://www.universetoday.com/wp-content/uploads/2016/06/Juno_trajectory_through_radiation_belts-580×400.png 580w” sizes=”(max-width: 612px) 100vw, 612px”/>

Orbit Juno around Jupiter will be very elliptical because it contradicts Jupiter's powerful radiation belts Image: NASA / JPL [19659only] a small amount of time close to Jupiter during each orbit, and the radiation is so intense that every close passage damages the spacecraft's electronics and instruments a bit, shortening their life span. After all, even if they are housed in a protective titanium vault, the tools will fail and the mission will end.

But a 12-hour period spent in the shadow of Jupiter would have ended the mission prematurely, with all its instruments intact and operational. This premature end would rob us of JunoCam's vast knowledge and marvelous imagery. So Juno, able to avoid the dangers, was instructed to avoid the darkness. This required resources in the form of a hydrazine reaction control system.

The Juno was never designed to travel in the dark. In fact, during his entire mission, he spent only 10 minutes in the dark when traveling in the beginning of the mission, traveled the Earth's shadow. This is because instead of an RTG (radioisotope thermoelectric generator) power source distributed in missions other than the Sun, Juno relies on solar energy for its operations. Juno is the first mission to travel so far from the sun with solar energy.

  Juno solar panels are being tested. Juno was never intended to travel in the dark. Solar panels are its power source and it does not have enough capacity to store batteries to survive 12 hours of darkness. Image Credit: Photo: NASA / Jack Pfaller - http://mediaarchive.ksc.nasa.gov/detail.cfm?mediaid=53133, Public Domain, https://commons.wikimedia.org/w/index.php ? curid = 15418531
Juno solar panels are being tested. Juno was never intended to travel in the dark. Solar panels are a power source and do not have enough capacity to store batteries to survive 12 hours of darkness. Image Credit: Photo: NASA / Jack Pfaller – http://mediaarchive.ksc.nasa.gov/detail.cfm?mediaid=53133, Public Domain, https://commons.wikimedia.org/w/index.php ? curid = 15418531

The spacecraft has three solar arrays that produce up to 490 watts at the beginning of the mission. But over time, the efficiency of solar arrays declines, so by the end of the mission they will only produce about 420 watts. But even at maximum efficiency, the Juno solar energy system simply won't help the spacecraft survive the 12 hours of darkness. Not enough battery capacity. And the batteries are heavy; you do not launch a spacecraft with extra batteries, just in case.

This is not the first wrinkle in the control of Juneau's orbit. In fact, this shadow escape maneuver is needed because of another change in Juno's orbit. When it first went into orbit around Jupiter, 53 days went into full orbit. The plan was to burn the traction and change the orbit for only 14 days. But when the engineers suspected the fuel supply problem, they maintained orbit for 53 days.

A shorter 14-day orbit would mean less time between science flights. Juneau will still complete all its orbits, but since Juno has been unable to reach the 14-day orbit, science is taking longer. So, although the original mission plan never had to withstand future 12-hour shadows, the plan was revised. That's why it took 10.5 hours of burns.

Ed Hearst – Project Manager for the Juno Project at NASA's Jet Propulsion Laboratory in Pasadena, California. In a press release, he praised both the skill of the team managing it and the versatility of the spacecraft itself.

"Planning a mission before launch did not involve a prolonged blackout that would plunge our solar-powered spacecraft into darkness," Hirst said. "What we could do was plan and perform the necessary maneuvering while in Jupiter's orbit. is a testament to our team's ingenuity and skill, as well as the extraordinary ability and versatility of our spacecraft. "

Managed by the Juno Mission on Jupiter. NASA Jet Propulsion Laboratory, launched on August 5, 2011, and launched into Jupiter 5 or tion 2016. The mission should end in July 2021, when the spacecraft plunged to its destruction in the atmosphere of Jupiter.

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