InSight project manager Tom Hoffman points at an image sent from the InSight lander after the space craft landed on Mars in the mission support area of the space flight operation facility at NASA's Jet Propulsion Laboratory in Pasadena, California. AP Photo/(Al Seib /Los Angeles Times via AP, Pool

Imagine you're trying to decide where to place your peg in a game of Battleship. Except let's change it up a bit. Instead of looking at a small grid, you're scanning an entire planet. And instead of looking for ships, you're trying to find evidence of microscopic life. And let's add another fun twist: There might not even be any actual "targets" for you to find.

Sound like something you'd be willing to bet more than $2bn on? Well, Nasa's done exactly that.

The InSight probe landed on a vast, flat plain known as Elysium Planitia, close to the Red Planet's equator, but the hugely expensive gamble intended to uncover the secrets of our planetary neighbour's cryptic past is likely to end up with more questions than answers.

And yet, this is among the most exciting space missions of our lifetime.

"I think, in the long run, this will be a no-brainer," said Thomas Zurbuchen, associate administrator at Nasa.

As head of the agency's science mission directorate, he's the man who called the multi-billion-dollar shot, shaping the search for life beyond our planet for the near future.

Zurbuchen recognises that the mission comes with risk. Nasa landed the rover using a rocket-powered sky crane - a mind-blowing manoeuvre in which a spacecraft barrelled into Mars' atmosphere at breakneck speeds and, with the help of a parachute and propulsion rockets, slowed down just enough to lower the rover onto the surface on cables in midair. Such a landing wasn't unprecedented, but engineers refer to the procedure as "seven minutes of terror".

Complicating matters is rough terrain full of boulders and sand dunes, but even if the rover manages to secure the samples it set out to collect, there's no guarantee that they'll ever be delivered to Earth for study. The plan is to launch another rocket to Mars in the future to retrieve those samples and bring them to Earth, but such missions have yet to be funded.

Zurbuchen also knows that plenty of scientists disagree that the ancient lake bed known as the Jezero crater is the best place to look for signs of ancient life on Mars. Others, for example, had proposed returning to the hot springs in the planet's Columbia Hills, where the Spirit rover explored almost a decade ago. Spirit didn't have the tools needed to search for life, but it did find structures similar to those created in part by extremophile bacteria in hot springs on Earth.

But in the end, only one landing site could be chosen, and Jezero was determined to be the best bet.

After all, if evidence of long-lost Martian life exists, it would make sense that it would be somewhere where there was once shallow water - hidden in the dried-up clay of the lake bed.

The Jezero mission is more than just a daunting engineering feat. It represents the first rover mission designed to seek signs of life beyond Earth. And if everything goes according to plan, it will be the first round-trip mission to another planet - a first step before humans make the trip themselves.

And so, in a way, the mission represents hope. At a time when government can't seem to accomplish very much at all, and when human beings don't seem to agree on even the most basic values, space missions such as this reach for other worlds and promise to do the impossible. (© Washington Post)

Irish Independent