Saturday, June 28, 2014

'Flying saucer' to test Mars tech

The US space agency (Nasa) is set to test what looks every inch like a flying saucer.

In reality, the Low Density Supersonic Decelerator (LDSD) is a demonstrator for the type of technologies humans will need to land on Mars.

The LDSD will be deployed from a high-altitude balloon off Hawaii.

It will trial a new type of parachute and an inflatable Kevlar ring that can help slow down a spacecraft as it approaches the Red Planet's surface.

Nasa says it is trying to raise the current maximum mass that can be put on Mars from 1.5 tonnes to something nearer the 20-30 tonnes a human mission might require.

Ian Clark, the LDSD's principal investigator told BBC News: 'We're testing technologies that will enable us to land bigger payloads, much heavier payloads, at higher altitude and with more accuracy than we've ever been able to do before.'

The test is taking place at the US Navy's Pacific Missile Range Facility in Kauai, Hawaii.

A helium balloon will lift the LDSD to about 35km (120,000ft) before releasing it.

A rocket motor will then kick the vehicle on up to about 55km (180,000ft) and a velocity of about Mach 4 (four times the speed of sound).

As the LDSD begins to slow, it will deploy its two new atmospheric braking systems.

The first to come out will be the 6m (20ft) inflatable 'donut'. This will increase the vehicle's size and also, as a result, its drag.

Once the velocity has dropped to about Mach 2.5, the parachute will come out.

'The supersonic parachute we're testing is enormous,' says Ian Clark.

'It's 100ft (30m) in diameter; it generates two-and-a-half times the drag of any previous parachute we've sent to Mars. We're going to use it at a velocity that's faster than we've used a parachute at Mars.

'We're really going to push it to the edge where the materials themselves, the nylons and Kevlars that the parachute is made of, may start melting.

'We don't know; that's why we do this testing.'

Assuming the structures all stay intact, the parachute should drop the LDSD in the ocean after about 45 minutes.

Nasa's plan is to return next year with a larger ring and parachute to test.

The Curiosity rover, at one tonne, is the biggest object landed on Mars to date.

There is a recognition that this payload capability will have to be increased substantially if astronauts on the planet are to receive all the food supplies and equipment they need to survive.