Thanks to a mission extension, NASA’s Juno probe continues to orbit Jupiter, being only the second spacecraft in history to do so. Since it arrived around the gas giant on July 5th, 2016, Juno has managed to gather a great deal of information on Jupiter’s atmosphere, magnetic and gravity environment, and its interior structure.
In the early 1960s, scientists developed the gravity-assist method, where a spacecraft would conduct a flyby of a major body in order to increase its speed. Many notable missions have used this technique, including the Pioneer, Voyager, Galileo, Cassini, and New Horizons missions. In the course of many of these flybys, scientists have noted an anomaly where the increase in the spacecraft’s speed did not accord with orbital models.
Ten months after its nerve-wracking arrival at Jupiter, NASA’s Juno mission has started to deliver – forcing scientists to reevaluate what they thought they knew about the giant planet. The first findings from Juno, published in Science, indicate that many aspects of Jupiter have defied expectation – including the strength of its magnetic field, the shape of its core, the distribution of ammonia gas and the weather at its poles. It certainly makes this an exciting time to be a Jupiter scientist.
On July 4th, 2016, the Juno mission established orbit around Jupiter, becoming the second spacecraft in history to do so (after the Galileo probe). Since then, the probe has been in a regular 53.4-day orbit (known as perijove), moving between the poles to avoid the worst of its radiation belts. Originally, Juno’s mission scientists had been hoping to reduce its orbit to a 14-day cycle so the probe could make more passes to gather more data.
Jupiter may be the largest planet in the Solar System with a diameter 11 times that of Earth, but it pales in comparison to its own magnetosphere. The planet’s magnetic domain extends sunward at least 3 million miles (5 million km) and on the back side all the way to Saturn for a total of 407 million miles or more than 400 times the size of the Sun.
The Juno spacecraft made history on July 4th, 2016, when it became the second spacecraft in history to achieve orbit around Jupiter for the sake of a long-term mission. Following in the footsteps of the Galileo mission, the probe will spend the next 20 months gathering data on Jupiter’s atmosphere, clouds, interior and gravitational and magnetic fields, before purposefully crashing into the planet.
Five years after departing Earth, and a month after slipping into orbit around Jupiter, NASA's Juno spacecraft is nearing a turning point. On July 31 at 12:41 p.m. PDT (3:41 p.m. EDT), Juno will reach the farthest point in its orbit of Jupiter for the first time, known as “apojove,” 5 million miles (8.1 million kilometers) from the giant planet. After that point, Jupiter's gravitational grip on Juno will cause the spacecraft to begin falling back toward the planet for another pass, this time with its scientific eyes wide open.
This year is shaping up to be another exciting one for space after a bonanza of discoveries and celestial events in 2015. One of my hoped-for highlights of 2016, NASA’s Insight mission, has unfortunately been scrubbed due to a serious leak in last stage testing. But here are three of my particular favourite space missions to watch out for as well as some key night sky events to try and experience throughout 2016.