Under the radar visit by Juno head

Thursday, 4 August 2016

It's been a month since Nasa's space craft Juno successfully went into orbit around Jupiter, but mission head Dr Scott Bolton was still excited about it when he visited the Warkworth Radio Astronomical Observatory last week.

Its been a busy and intense time for the space physicist and his trip to Australia and New Zealand visiting radio telescope sites used at times for some of the United States space agency's research was something of a relief for Bolton who with his family are also planning on a short holiday here.

Surprisingly Bolton credits his involvement  with space research, initially as an aerospace engineer, on the good luck of having a father involved in the toy industry.

Along with painting and drawing kits he also had access to model construction kits. With no issues around getting hold of extra bits for building young Bolton's imagination soared and set him firmly on an engineering career pathway.  Contact with Nasa saw him complete a PhD in astrophysics and move into planetary exploration.

Along with his work with JPL - attached to Nasa - Bolton is also director of the Southwest Research Institute with his research focusing on the giant planets and the origin of the solar system.

Taking five years and a journey of 2.8 billion kilometres to reach Jupiter much has been made over Juno being the first deep space probe to only use solar power. All other probes have used nuclear power including Galileo the only other probe to orbit Jupiter arriving in 1995, which Bolton was also involved with.

A shortage of material needed for nuclear power was behind the decision to go with solar panels rather than any altruistic reasons, he says and keeping the panels facing the sun did make aspects of the mission harder, he says.

After swinging back close to the earth two years after launch, using our gravity to sling shot the craft on it's journey, then getting caught in Jupiter's intense gravity made Juno easily the fastest space craft ever, travelling at 266,000 km/h (74 km/s).

Communication time delays meant the manoeuvre to slow down and get into orbit around the colossal planet was executed completely by the probe and saw a tense team back on earth erupt with jubilation when successful. 

With Jupiter five times the distance of the earth from the sun the panels are only picking up four percent of the light they were getting on earth, but still enough to operate the craft.

The environment around Jupiter is harsh with strong radiation coming from the colossal planets magnetic field.

A radiation vault helps protect Juno's research instruments and 'brain'. An elliptical orbit will keep it away from the worst of the radiation though it will still come to within 5,000 kilometres of the cloud tops at its closest approach.

Even with these precautions some of the instrumentation on board is expected to fail before the end of the mission.

The 37 orbits planned over 20 months will be around the poles to get as much information about the planets powerful magnetic fields that are also driving the most intense aurora's in the solar system including particles flowing between the closest moons and the planets atmosphere.

Concerns some form of life from earth may have survived on the craft and could contaminate potentially life harbouring moons means Juno will dive into Jupiters atmosphere, evaporating in the intense heat and pressure, at the end of the mission.

Acknowledging this also slightly alters Jupiters atmosphere its much less likely that life we could recognise would exist in that extreme environment, Bolton says.

There is no scientific case for a camera but Bolton insisted one should be aboard and used the outreach programme fund to get a cheaper version of one sent to Mars. Taking the public and youngsters along for the ride is an important part of the mission for him and partly why three metal LEGO characters representing the Roman god Jupiter, his wife Juno and Galileo Galilei are on board. LEGO is one of the companies sponsoring the outreach part of the mission.

'I can't imagine going all the way to Jupiter and not taking images in visible light, and these little guys are getting a great view.' 

Better understand of how Jupiter was formed is the most important part from a science perspective, Bolton says, as it will help to clarify how our solar system and others came about.

Some puzzling aspects of the makeup of gas giant include the possiblity of planet migration, where Jupiter may have formed much further out and is slowly being drawn in closer to the sun. 

The make up of it's thick atmosphere, the gravitational and magnetic fields, and the composition of the core will also be looked at.

And while Jupiter and the Juno project has consumed him for over 15 years surprisingly it is the far flung Neptune 30 times further out than the earth from the sun that fascinates Bolton the most.

'I hope I'm still around to see a similar mission there,' he says.

But taking on another mission like Juno is unlikely for Bolton. It's pretty full on and a very big investment of time, he says.

Whether New Zealands closer ties with Nasa will see more work for the northern observatory, with the only research quality radio telescopes in the country is unclear.

Our position in the South Pacific makes us a important cog for low earth orbit tracking and for distant research using Very Long Baseline Interferometry (VLBI) as part of radio telescope arrays with Australia.

AUT's Institute of Radio Astronomy and Space Research which operates the Warkworth observatory already has a contract to track California based SpaceX craft dragon as it supplies the International Space Station with flights carrying astronauts due to start next year. 

Nasa is now supporting plans by SpaceX to send an uncrewed red dragon space craft  to Mars as early as 2018, and Warkworth observatory may also be involved.

Though previously involved with European Space Agency (ESA) Mars Express and the Rosetta craft orbiting comet 67P/Churyumov-Gerasimenko observatory director Professor Sergei Gulyaev says it is too soon to say if they will also become involved with the Juno mission or Nasa's other Deep Space projects.

Not sure that he would do another mission like Juno - pretty full on and a very big investment of time.

To capture the imagination and left the human spirit

The camera on board couldn't be justified for any scientific reason but it just didn't seem right to go all the way to jupiter and not take images so got the funding for it through the outreach programme.

Jupiter - not sure how it formed. Its made of a lot of the heavy elaments - much more so than any of the other planets and so it seems to have formed early compared to the other planets but what's at its centre. If its solid rock then the gas atmosphere must have formed around it later aasteroids hitting it burn up and evaporate in the atmosphere and never reach the centre.