We should know by early Monday morning whether NASA's most ambitious Mars probe yet has landed alive – or as a $2.5 billion pile of junk.
The Curiosity Rover is supposed to touch down just after midnight on Sunday night, Houston time, then open its electronic eyes and take a look around.
NASA has dispatched probes to the red planet before, but never quite like this.
"It's an unprecedented mission," said Nathan Moeller, a space enthusiast who was touring the Johnson Space Center on Friday. "You have the largest rover in history headed towards Mars -- it's the size of a Mini Cooper. And the way they're going to try and land this thing? It's gutsy."
The touchdown involves a heat shield, a parachute, rocket thrusters and a sky crane. In that order.
The landing is completely computer-controlled, with zero opportunities for human intervention in case of unforeseen events.
Assuming NASA is successful, it will have planted a roving laboratory on Mars, capable of collecting and analyzing samples for two years.
The goal? Sniff out clues that may – or may not – point to evidence of life on Mars.
"This rover is equipped with the ability to measure organics - carbon compounds - and because of that we'll be able to determine whether or not this place has ever been capable of supporting life," said Michael Meyer,
NASA's lead scientist on the Mars Exploration Program.
The space agency's ultimate aim is to be able to send astronauts to Mars someday. But will they succeed?
"In my lifetime? I don't know about that, but I know they're going," said Marlene Morgan, an educator and space buff who also spent Friday at JSC.
"I think it's the next great step in human exploration," added Moeller.
Such red planet pioneers might well be someone like NASA Mission Specialist Alvin Drew, who's logged 612 hours in space on two separate shuttle missions.
"I think going to Mars for me would be a very surreal experience," Drew told FOX 26 News. "I'm used to flying about maybe 250 to 400 miles away in space: the distance from Houston to Dallas, straight up, that's about it. Going to Mars would be about a million times that distance."
It is so far away, in fact, it'll take 14 minutes for data to travel from Curiosity to Earth…making Monday morning's spectacular landing even more of a nail-biter.
You can follow along on NASA's U-Stream channel, here:
Also, check out the mission's Twitter stream, @MarsCuriosity, search for hashtag #MSL, or visit Curiosity's Facebook page here: