Nasa readies giant Moon rocket

NEW YORK, Aug 17 (BBC): The American space agency Nasa is rolling out its giant new Moon rocket to prepare it for a maiden flight.
Known as the Space Launch System (SLS), the vehicle is being taken to Pad 39B at the Kennedy Space Center in Florida for a lift-off scheduled for 29 August.
The debut outing is a test with no crew aboard, but future missions will send astronauts back to the lunar surface for the first time in over 50 years.
The near 100m-tall (328ft) SLS is riding an immense tractor to the pad.
It started moving from its assembly building at Kennedy late on Tuesday evening, local time, but with a cruising speed of just over 1km/h (under 1mph), it could take 8-10 hours to complete the 6.7km (4.2 miles) journey.
This is a key moment for Nasa, which will celebrate in December the half-century anniversary of Apollo 17, the very last human landing on the Moon.
The agency has vowed to return with its new Artemis programme, using technology that befits the modern era (Artemis was Greek god Apollo's twin sister and goddess of the Moon).
Nasa sees a return to the Moon as a way to prepare to go to Mars with astronauts sometime in the 2030s or soon after.
The SLS will have 15% more thrust off the pad than Apollo's Saturn V rockets. This extra power, combined with further enhancements, will allow the vehicle to not only send astronauts far beyond Earth but, additionally, so much equipment and cargo that those crews could stay away for extended periods.
The crew capsule, also, is a step up in capability. Called Orion, it is much more spacious, being a metre wider, at 5m (16.5ft), than the historic command modules of the 1960s and 70s.
"To all of us that gaze up at the Moon, dreaming of the day humankind returns to the lunar surface - folks, we're here! We are going back. And that journey, our journey, begins with Artemis 1," said Nasa Administrator Bill Nelson.