Mars © Catalyst Images Mars In just the last few months, we’ve learned of new evidence that complex organic molecules—ostensibly the constituent ingredients for life—have been preserved in Martian rocks; that Mars’ atmosphere exhibits seasonal variations of methane, a potential chemical signature of life; and that a huge reservoir of liquid water exists under the surface of the planet itself.Each of those discoveries thickens the plot in the search for extraterrestrial organisms and teases us into believing we might soon find the first evidence ever that life elsewhere exists.And while signs of alien life that lived long ago would be groundbreaking, the bigger question people have is: What does Mars mean for the future of life as we know it? Photo Illustration by The Daily Beast © Provided by The Daily Beast Photo Illustration by The Daily Beast Life on Mars would be a brilliant thing to witness. It would be a mistake, however, to presume this past summer’s news means we’re likely to see something of that scale unfold.

Those reasons start with the fact that the 4.6 billion year history of Mars is a complicated, tragic tale.

Ancient Mars was a much different planet from its current form. In fact, it was similar to Earth.

Mars © Catalyst Images Mars It was brimming with a thick atmosphere that kept things warmer, protected by a magnetic field that could stop cosmic radiation and UV rays from sterilizing the surface, and almost certainly teeming with vast bodies of liquid water on the surface of the planet that could support life as we know it.

“There’s not a consensus, but there’s a general expectation [ancient] Mars must have been looking like a good summer Arctic day,” Nathalie Cabrol, a NASA astrobiologist who is extensively involved with the search for signs of extraterrestrials on Mars, told The Daily Beast.

For life to exist, “you need energy, you need water, you need nutrients, and you need a shelter, and you have all of these on an early Mars. If you want a time where life could have started, early Mars would have been the time.”

Mars © Catalyst Images Mars That’s a far cry from what Mars looks like today. Even under the most ideal conditions, like a summer’s day, Mars temperatures might tick up to nearly 70 degrees Fahrenheit.

But at night, temperatures plummet down to lower than -100 degrees.

That’s not even considering how much colder things are near the poles or during the winter months.

There’s no strong atmosphere to keep the climate warm and temperate for humans.

Mars © Catalyst Images Mars And Mars lost its magnetic field a long time ago, which means radiation would zap anything that’s hanging around on the surface anyway.

“I always compare this to cuisine,” Cabrol said. “You have ingredients on the table. Two people can take those ingredients and get the same results.

But if one is a great chef and one doesn’t know anything about cooking, you will end up with two very different things.”

Those two sets of hands in the kitchen are Earth and Mars, respectively. And while Earth whipped up a dish of biological delights, Mars may have barely made something edible, if it even managed that.

Mars © Catalyst Images Mars Three months ago, the Curiosity Rover stumbled upon a three-mile high mountain—the Gale crater—near the Martian equator with a valley that seemed to contain methane, a sign of primitive, organic life.

But researchers restrained their excitement, because of the structure of the organics themselves.

“The chemical structure [of the molecules], as far as we understand, is rather random,” said Roger Everett Summons, an MIT researcher of planetary science and a member of the team that made the Gale crater discovery.

They are, chemically speaking, the buildings blocks of life, but they lack the sort of organization that actually allows them to be constructed into life. It’s a bit like seeing concrete cut into fine blocks, versus seeing concrete that’s just cut into any sort of odd shape you can think of.

Mars © Catalyst Images Mars “The fact that [these organics are] still there after millions of years of radiation—cosmic rays and UV—says something about the stability of those materials,” said Summons. “But it doesn’t say anything about the origins.”

Summons believes the organic molecules, due to their structure, weren’t formed on Mars, but instead came to the red planet aboard meteorites.

Dirk Schulze-Makuch, a German astrobiologist and a professor at the Technical University of Berlin, interprets the structure of the organics differently, and believes they could be signs of past alien life.

Related: Fascinating photos of Mars (Provided by Photo Services)