(Web Desk) - Nasa is planning to send a drone to a nearby moon that will hunt for alien life.

The Dragonfly probe will explore Titan, Saturn's largest moon – around 745 million miles from Earth.

That might sound like a vast distance, but it's a stone's throw in space terms.

The launch is set to take place in July 2028, with the Dragonfly rotorcraft reaching Titan in 2034.

Nasa first announced the mission back in 2019, and we're now just under four years away from the full launch.

"With the Dragonfly mission, NASA will once again do what no one else can do," said then-NASA Administrator Jim Bridenstine, speaking at the time.

"Visiting this mysterious ocean world could revolutionize what we know about life in the universe.

"This cutting-edge mission would have been unthinkable even just a few years ago, but we’re now ready for Dragonfly’s amazing flight."

Titan is a giant moon – the second biggest in our solar system, and even larger than the planet Mercury.

Nasa says it has a nitrogen-based atmosphere like Earth – but its clouds and rain are methane.

And its surface temperature is a staggeringly low -179C / -290F.

To help Nasa's Dragonfly survive on Titan, the space agency has used Cassini data to choose a period of calm weather for landing.

It'll begin its exploration at dune fields along the equator, which Nasa says are like the ones in Namibia.

Initially Dragonfly will explore in short flights.

But this will eventually grow to longer five-mile flights, during which it will collect samples.

Its ultimate destination is the Selk impact crater, where Nasa hopes to find evidence of past – or even living – alien life.
"The lander will eventually fly more than 108 miles (175 kilometers) – nearly double the distance traveled to date by all the Mars rovers combined," Nasa said.

Nasa says that the Dragonfly will launch "no earlier than July 2028", after achieving final approval for the mission in April this year.

It's going to cost around $3.35 billion (£2.6 billion) over its full lifecycle – roughly double the proposed bill from 2019.

"Dragonfly is a spectacular science mission with broad community interest, and we are excited to take the next steps on this mission," said Nasa's Nicky Fox, associate administrator of the Science Mission Directorate.

"Exploring Titan will push the boundaries of what we can do with rotorcraft outside of Earth."

The craft itself is being built in Laurel, Maryland, at the Johns Hopkins Applied Physics Laboratory.

It will be a breakthrough mission that makes space history.
Nasa explains: "The rotorcraft, targeted to arrive at Titan in 2034, will fly to dozens of promising locations on the moon, looking for prebiotic chemical processes common on both Titan and the early Earth before life developed.

"Dragonfly marks the first time Nasa will fly a vehicle for science on another planetary body. The rotorcraft has eight rotors and flies like a large drone."

Titan has low gravity, a dense atmosphere, and low levels of wind, which should make it relatively easy for Dragonfly to fly.

The craft is expected to weigh around 990lb (450 kilos), and will be packed inside a 12-foot heatshield.

During Titan nights – which last around 192 hours – Dragonfly will remain on the ground.