The Juno Spacecraft
(Originally posted July 04, 2016 on Blogger)
Last night I went over to a friend's house to planet gaze... Saturn, Mars, and Jupiter were in view and he just finished rebuilding his 30-inch Dobsonian complete with this dome! He retired from JPL in Pasadena years ago, and now spends his time doing photometry as a hobby. His wife joked at how much time he spends under the dome, "I don't know what he does out there, but sometimes I have to go make sure he's still alive!" I've wanted to build a (much smaller) Dobsonian-mounted telescope since last summer, when another friend of mine showed me how it can be done for cheap, but I've yet to get around to it.
While looking at Jupiter, another friend of his who works at a solar observatory commented on the Juno mission to that planet. The Juno mission's goals are to look deep beneath Jupiter's outer gas layers to see what lies within, and, among other things, finally answer the question of whether Jupiter's core is solid or not.
I remember when the Juno spacecraft was to be launched back in 2011. Its launch was delayed due to a helium leak, and I specifically remember thinking about how we waste that precious resource on party balloons! Helium is one of the most abundant elements in the Universe, but here on Earth it is one of the most rare. And though the price of helium has gone up 500% in the past 15 years or so, this still doesn't accurately reflect its true 'value'. Unlike diamonds, helium (He) is actually worth something. This noble gas is routinely used in science; The Large Hadron Collider (LHC), currently the world's largest and most powerful particle collider and easily the single biggest machine on Earth, uses an isotope of He to keep its magnets cool at 1.9 Kelvin (K). It's used in liquid form in MRIs to cool magnets as well. This magnet-cooling business is extremely important for reasons of superconductivity. There are numerous other uses for He in science, so party balloons need to switch to hydrogen and stop wasting ... wait.. no, that's a bad idea. Nevermind! ...though last week I read that a 'huge' deposit of He was discovered deep underground in Tanzania... enough to "...fill a million medical MRI scanners" according to geologists at Durham and Oxford universities. Though that is another blog topic altogether...
At any rate, once the He leak was resolved, Juno was launched, and the spacecraft is arriving to within 5,000 km of Jupiter tomorrow! Wow! Time flies when you're old like me. :( Helium is one resource Jupiter has an abundance of! In fact, Jupiter is very similar to stars in that it is, insofar as we know, comprised primarily of hydrogen and helium. It will be a nervous day for the awesome folks at JPL who will be controlling Juno, as well as the amazing engineers in Westcott, Buckinghamshire who designed and built the Leros-1b. Jupiter is a behemoth of a planet, but traveling as much as 38,000 km/hr, Juno will need to turn its back to the direction in which it is going, and fire that Leros-1b for 20 seconds, in which time it needs to slow its relative speed down by 500 m/s in order to be captured by Jupiter's gravity. If it fails (which it won't!), the BBC news site writes, "...[it] would send Juno in the oblivion of deep space"!
At a cost of 1.1 billion US dollars, and 5 years of waiting... that would be a terrible outcome to say the least. But the Leros-1b (I wonder if it is named after the Greek island?) has been used successfully before, and on this very mission, when in 2012 it was used to complete a maneuver of the Juno spacecraft. So confidence is as high as nerves are frayed I'd imagine!
I love the name given to the spacecraft: Juno. Juno is the Roman equivalent to the Greek goddess Hera. Hera's jealousy is the stuff of legend, and rightfully so.. her husband-slash-brother, Zeus, was a promiscuous one. At one point, Zeus tried to hide his promiscuous ways from Hera by surrounding himself in a thick blanket of clouds. But Hera saw RIGHT THROUGH THE CLOUDS. I should also say that I believe Hera's infamous jealousy was not the way she was known in the beginning. Perhaps another blog for more on that...
At any rate, Juno's mission is to peer through the thick veil of clouds of Jupiter, to see what mischief is going on beneath. I'd give the ones who came up with the name Juno for this spacecraft an A+ for cleverness; a trait Aristotle said is a necessary condition for practical knowledge when he spoke of virtues (albeit cleverness received a neutral-morality grade).
Juno is really going to open the lid on Jupiter in the coming 3 years, and I can't wait to hear what new discoveries and answers come of it. The Great Red Spot, that storm that has been raging for over 3 centuries... how deep does it go? The core... is it solid? I think it is solid... to do with the Grand Tack... but that's another blog. And ultimately, scientists hope to answer fundamental questions regarding Jupiter's origins.. questions that may give insight on the other gas giants, Uranus and Neptune (and that 9th planet way out there that is yet to be seen... if in fact it is a gas giant).