After an eight-month voyage of 350 million miles, NASA's Mars rover is making its final approach.
The robotic lab, dubbed Curiosity, is due to land on the Red Planet on Sunday (August 5) night.
But engineers say landing the one-ton spacecraft is risky.
SOUNDBITE: ASHWIN VASAVADA, DEPUTY PROJECT SCIENTIST - JET PROPULSION LABORATORY SAYING (English):
"We've designed the spacecraft to basically handle all the conditions we've seen in past years whether they are clear or dusty but we continue to monitor it in real time getting data from the orbiters at Mars every day this week to make sure we understand what conditions the spacecraft will encounter as it's flying through the atmosphere and just how accurately we can expect to land."
The rover is essentially flying on automatic pilot, guided by pre-programmed instructions.
As it starts the decent, controllers have an anxious wait to see whether it lands in one piece.
SOUNDBITE: DOUG MCCUISTION, MARS EXPLORATION PROGRAM DIRECTOR, SAYING (English):
"If we're not successful, we're going to learn, we're going to learn from this. We've learned in the past and we've recovered from it. We'll pick ourselves up, we'll dust ourselves off, we'll look at ourselves and do something again, we'll do it again. This will not be the end."
If the rover touches down successfully it will begin unlocking clues about possible life on Mars.
Sarah Charlton, Reuters.
