Carlos Bacigalupo is one of our astronomy guides and is currently completing his PhD at Macquarie University. Below he discusses Juno’s close encounter with the largest planet in our Solar System.
For the last four and a half years, the spacecraft Juno has been preparing to meet the largest planet in our solar system. On July 4th the trip will be finally over. The Juno mission to Jupiter aims to make the most accurate measurements of the gravitational and magnetic fields of this planet to this day. In order to achieve that, it will stabilise itself in a path that passes more than 5000km above its poles. If Jupiter would be the size of a football, Juno would be traveling less than 1 centimetre away from it.
When we look at maps of the giant planet, we notice that the polar areas are blurred out. This is because we don’t have enough information about that part of the planet. This is about to change when Juno arrives. The special trajectory that Juno will settle into is called a polar orbit. It’s a great way to allow the instruments to make measurements at different latitudes. It will be the first time that this type of orbit is attempted on Jupiter.
It will take 11 days for the spacecraft to complete an orbit. It takes about 10 hours for Jupiter to complete a full spin around its own axis. As the spacecraft slowly moves up (or down) the planet’s latitude, Jupiter will literally pass under it, exposing its many wonders. After 33 orbits, just about a year, the planet will be fully mapped and our vision of Jupiter will be changed forever.
There are several instruments aboard Juno aiming to measure the gravitational, magnetic and electric fields, the amount of water in the atmosphere and the chemistry of the clouds through ultra-violet spectroscopy. But it is the JunoCam that will allow us to fall in love with Jupiter’s views all over again. Communications will limit the data transferred from this camera to 40 megabytes per orbit, this means up to 1000 images. Nonetheless, at 15 km per pixel this is almost 8 times higher resolution than the Hubble space telescope ever achieved on this planet. So, starting in July, keep your eyes open for Jupiter’s new look.