In March 2015 , solar-powered aircraft Solar Impulse 2 took on the mammoth task of a round-the-world flight without a drop of fuel.
More than a year later, the plane successfully landed back Tuesday where it started and has managed to clock up a number of world records.
Dubbed as the "definition of adventure" by its pilots and having brought solar-powered technology to the forefront of people's minds, CNBC takes a look back at some of Solar Impulse 2's most noteworthy moments during its round-the-world trip.
The concept of Solar Impulse actually dates back to 1999, when pilot Bertrand Piccard flew around the globe in a balloon. On his trip with Brian Jones, Piccard became extremely conscious of the amount of fuel needed during the voyage; triggering a desire to ensure his next round-the-world flight was fuel and emissions-free.
Following years of research, Piccard officially founded the Solar Impulse project with fellow pilot, André Borschberg in 2004 and began working on the aircraft's first prototype. In December 2009, the first prototype took a successful short "flea hop" test – for 350 meters, one meter off the ground – and then went on to do its maiden flight in April 2010.
In 2014, the project's pilots and co-founders unveiled Solar Impulse 2 and took it on its first flight.
On March 9, 2015, Solar Impulse 2 (Si2) set about to create a world record : to fly around the world powered only by the sun, during the course of five months. Taking flight from the Abu Dhabi, Solar Impulse's CEO André Borschberg flew the plane for 13 hours to Muscat, Oman.
While the journey itself was seen as a first for many, for the pilots it was about promoting clean technologies and demonstrating what solar energy can do for current and future generations.
"In our world today, if we want a better quality of life, to create jobs, to make profit for the industry, to sustain growth for our world, we need new clean technologies, because this is what the world needs," Solar Impulse chairman, Bertrand Piccard told CNBC before the journey began.
The carbon-fiber aircraft itself weighs 2,300 kg, and is equipped with more than 17,240 solar cells stretched out on its wings, which helps power the propellers and electric engines.
After travelling to countries including India, China and Japan, Si2 took on its eighth and most challenging leg yet during the early hours (local time) of June 29, 2015: a five-day non-stop flight from Nagoya, in Japan to Kalaeloa, Hawaii.
Piloted by Borschberg, Si2 travelled for more than 8,900 km , achieving the world record for the longest non-stop solo flight.