NASA spacecraft Juno has, as of January the 13th, broken the interplanetary distance record for a solar-powered spacecraft. It broke the record set by the European Space Agency’s Rosetta spacecraft. The Rosetta’s orbit peaked at 492 million miles (792 million kilometres) when it approached the comet 67P/Churymov-Gerasimenko. The Juno spacecraft crossed the milestone to about 493 million miles (793 million kilometres) at 11 am PST (2.00 pm EST, 19.00 UTC).
The Juno was launched in 2011 with the idea of “pushing the edge of technology to help us learn about our origins”, according to Scott Bolton, a Juno principal investigator at Southwest Research Institute, San Antonio. The Juno spacecraft weighs four tons and has 30- foot-long solar arrays with 18,698 individual solar cells. The solar arrays allow Juno to produce 14 kilowatts of electricity on Earth.
However, planet Earth is only 149.6 million kilometres. The sunshine here is strong enough to empower the craft to generate huge amounts of electricity. The real problem begins when the craft heads closer over to the gas giant. Jupiter’s humungous size makes for a pretty large shadow, due to which the power generation in the craft will decrease significantly. As of now, Juno is 517 million miles away from the sun and is therefore basking in only 1/25th of the sunlight, as compared to what we receive here on Earth. All of this information about Juno’s progress regarding power production was provided by Rick Nybakken, Juno’s project manager from NASA’s Jet Propulsion Laboratory in Pasadena, California.
Prior to Juno, eight other spacecrafts have navigated the harsher climates of deep space as far as Jupiter, powered by nuclear sources. Juno is set to arrive at Jupiter on the 4th of July. It will orbit the planet 33 times and fly by 3100 miles of the clouds of the planet. Jupiter is the first Jovian planet in the solar system, followed by Saturn. The purpose of using a solar-powered spacecraft was made clear by Scott Bolton as he said—
“We use every known technique to see through Jupiter’s clouds and reveal the secrets Jupiter holds of our solar system’s early history. It just seems right that the sun is helping us learn about the origin of Jupiter and the other planets that orbit it.”
Juno’s mission is organised in a manner so as to avoid Jupiter’s large shadow and its improved solar cell performance and a polar orbit that minimizes total radiation makes solar power possible on Juno. The objective of the Juno is to learn about the formation of the gaseous planet, about its structure, atmosphere, magnetosphere and its origins so as to throw light on our origins.