One of the many stunning shots of Jupiter - this time showing its southern hemisphere - captured by the Juno spacecraft.
NASA/JPL-Caltech/SwRI/MSSS/Kevin M. Gill
Right now, a NASA spacecraft is preparing to jump over Jupiter’s shadow. If it doesn’t, it’ll die.
The Juno spacecraft popped along to the solar system’s biggest planet in the summer of 2016, hoping to better understand the birth, life and evolution of the churning gas giant through various technological means. It’s completed nearly two-dozen close flybys of Jupiter since, and it has a few more of them left before it meets its planned demise in the storms of the vaporous maw in July 2021.
It’s not a simple matter of simply swinging around Jupiter. Juno, with its limited fuel, must sometimes make a change in its orbit in order to make sure it can get in the right position to see a part of Jupiter that scientists are interested in. In this case, it’s shifting its trajectory in order to save its life.
As explained in a recent press release from the Juno mission team, it began a readjustment manoeuvre on September 30th, completing it 10.5 hours later on October 1st. During this rather long burn, it used 73 kilograms (160 pounds) of precious fuel to make sure it was moving out of the way of Jupiter’s rather sizeable shadow.
Being far further from the sun than Earth, Jupiter receives about 25 times less sunlight than we do. That also applies to any spacecraft dancing around it, meaning that a solar powered probe needs all the solar exposure that it can get. If it allowed itself to go into Jupiter’s shadow for 12 hours, as would have happened if it didn’t burn off that fuel, it would have proved fatal: in that dark umbrella, the solar power systems keeping its communications and observational equipment functioning would have likely run out of juice.
What Juno will see as it zooms toward Jupiter for its next close flyby while avoiding slipping into the gas giant's shadow. The sun can be seen just to the left of the planet, moving "up" with respect to the spacecraft during the evasive move.
NASA/JPL-Caltech/SWRI
If it somehow survived this particular brand of oblivion, it would have probably just found itself in another. The frigid temperatures in the darkness behind Jupiter would have caused the metal marvel to seize up and fail to respond to Earth’s orders when it emerged back into the light.
But wait – how did the Juno mission team, who surely carefully plotted out the orbital dynamics of the spacecraft long in advance, not realise that an orbit would put it in this lethal path? As it happens, this moment of peril finds its genesis way back when Juno’s mission around Jupiter began in earnest.
An artist's concept of Juno in position around Jupiter.
NASA/JPL-Caltech
When Juno first began zipping around the gas giant on July 4th 2016, it entered a 53-day-long orbit. The plan was to then reduce its orbits to 14-day circumnavigations in order to up the rate of science being conducted on Jupiter. But the team had some concerns about the fuel delivery system of the spacecraft, so, playing it safe, they decided to keep the orbits 53 days long. Juno would still be delivering the same science, but we would all just need a little more patience to see the results.
This meant that the original trajectories of the spacecraft weren’t the ones it would end up taking. Ultimately, this led it to the scenario it’s currently faced with: potentially plunging into the largest shadow imaginable and perishing. “Pre-launch mission planning did not anticipate a lengthy eclipse that would plunge our solar-powered spacecraft into darkness,” said Ed Hirst, Juno project manager at NASA's Jet Propulsion Laboratory in Pasadena, California.
Fortunately, presented with several options, it seems the team opted for a lengthy fuel burn to allow Juno to hop over the deathly eclipse on November 3rd. “Jumping over the shadow was an amazingly creative solution to what seemed like a fatal geometry,” said Scott Bolton, Juno principal investigator at the Southwest Research Institute in San Antonio.
I don’t know about you, but the fact that scientists can somewhat casually just leap over Jupiter’s titanic shadow to save it from an untimely demise is seriously cool stuff.
#News | https://sciencespies.com/news/a-nasa-spacecraft-is-about-to-leap-over-jupiters-shadow-to-save-its-life/
No comments:
Post a Comment