NASA has confirmed that the Juno space probe successfully entered the planet Jupiter’s orbit. In the last hours it conducted a series of maneuvers to reach the correct trajectory and speed to be captured by Jupiter’s gravity. In this period, Juno’s radio signals take about 48 minutes to reach Earth but in the end came the confirmation that the probe is in orbit and its solar panels are properly pointed toward the Sun.
The Juno space probe was launched on August 5, 2011 on an Atlas V 551 rocket. Its journey lasted almost exactly five years and is the second mission of NASA’s New Frontiers program that aims to run very specialized space missions at costs not higher than $700 million. The first mission is New Horizons, which on July 14, 2015 allowed us to really get to know the dwarf planet Pluto and its moons through a flyby.
The Juno mission is focused on the study of the planet Jupiter through a number of instruments. Over the course of 20 months it will orbit Jupiter 20 times to study its structure and general dynamics through very precise measures of its mass, the size of tis nucleus, its gravitational and magnetic fields, to analyze its atmosphere and to study planetary poles’ magnetosphere.
The planet Jupiter was already the target of NASA’s Galileo mission between 1995 and 2003, a space probe that was equipped with radioisotope thermoelectric generators to generate the power it needs. Instead Juno is equipped with solar panels almost 9 meters (29 feet) long each, becoming the farthest space probe from the Sun to use this type of power generation. That’s thanks to the progress made in the meantime by this type of technology and the lack of plutonium-238.
In addition to on-board systems, Juno brings an aluminum plate that reproduces the manuscript in which Galileo Galilei described for the first time the four largest moons of Jupiter after discovering them. That’s te reason why they’re called Galilean. There are also three aluminum LEGO minifigures depicting Galileo, Jupiter and Juno that are designed to try to catch children’s interest in the mission.
Now Juno is orbiting the planet Jupiter’s poles, where its powerful magnetic field is less intense and the solar panels can remain pointed toward the Sun. For a few weeks the mission engineers will test Juno’s systems calibrating the various systems with the first detections. The research phase will begin officially in October to uncover the last secrets of Jupiter and better understand gas giants in general.
NASA has put online a video with an animation of the Juno space probe’s approach to Jupiter and the Galilean moons.