Alien life might be closer than we had thought

Such was the ensuing media frenzy, Obama felt compelled to clarify his comments shortly after, saying there was a statistical likelihood of extraterrestrial life but that the distances between solar systems made it highly unlikely Earth had been visited by aliens.

Turns out evidence of alien life might well have been discovered much closer to home.

Drilling into what was thought to be an ancient lake bed in the Gale Crater on Mars last year, NASA's Curiosity rover detected long-chain molecules called alkenes which scientists believe might be chemical markers of ancient life on our near neighbour. Alkenes could have been derived from fatty acids associated with cellular membranes.

It's not conclusive evidence Mars once teemed with life before it lost its atmosphere but it is compelling. The high concentrations of the alkenes in the Martian mudflat makes it unlikely the organic molecules were deposited by non-biological means such as meteorites or space dust. They tried but the team of scientists examining Curiosity's data could find no explanation other than a biological one for the existence of these molecules.

This fascinating theory comes on the heels of research into how Mars would have looked if its giant canyons were filled with water. Examining satellite data, scientists concluded that geological structures on Mars closely resembled those on Earth fashioned by rivers, especially the fan shaped deltas formed when rivers flow into the sea. Their work lends further weight to the theory that the red planet was once blue and could have supported life.

Analysis of Martian rocks with unusual light dots is also intriguing. Scientists suspect the dots are traces of kaolinite clay, which on Earth is formed by persistent rain leeching all other minerals from it. On our planet, kaolinite is most often found in wet tropical zones - by their very nature incubators of life.

It will be years, decades, perhaps centuries before we know for certain whether Mars once hosted life or not but these signposts that it might have are intriguing.

And they are certainly much more compelling than the conspiracy theories that alien life forms are buried under Area 51 as part of some sinister deep state cover-up. A bid to expose the alleged cover-up was mounted in 2019 when more than a million Americans signed up to "storm" the facility. When the day came only 150 people showed up and a few were arrested. It was a damp squib.

Digging on Mars is far more fruitful in the search for evidence of alien life than wild imaginings about what's under Area 51.

As Barack Obama said when clarifying his earlier comments about the existence of aliens, "I saw no evidence during my presidency that extraterrestrials have made contact with us. Really!"

HAVE YOUR SAY: Is it statistically likely there is extraterrestrial life out there? Can research into the Martian past help humanity navigate the future? Were you a fan of The X Files? Or do you hold it responsible for the epidemic of conspiracy theories we have to contend with a quarter of a century after it was broadcast? Email us: echidna@theechidna.com.au

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THEY SAID IT: "Just as Mars - a desert planet - gives us insights into global climate change on Earth, the promise awaits for bringing back to life portions of the red planet through the application of Earth science to its similar chemistry, possibly reawakening its life-bearing potential." - Buzz Aldrin

YOU SAID IT: Once again rabbits are on the move and the potential for environmental disaster grows by the day. But funding for new biological control research dried up in 2022.

Thanks to Jen and Janet, who sent photos of brazen rabbits outside the National Library and Science Dome in Canberra.

"Why as a nation aren't we eating this low-fat, high-iron meat ?" asks Annie. "You need to know how to check their liver and kidneys to make sure they are healthy. Not rocket science. Live traps work."

Elias, who's noticed more rabbits around his home in Canberra, writes: "I already spend a bit of time on weekends helping local landholders shoot rabbits, and my family and our dogs enjoy the harvested rabbit meat. I think your article reveals that it would be silly to wait another five to 10 years for a biological solution that may come and may only be temporary. How about the government fund some micro-abattoirs and accredit more shooters to remove rabbits from farms and properties where their numbers are increasing and doing environmental damage?"

"They are everywhere," writes Bill. "We had a park close by that was closed while the local government attempted an eradication program. Seems to work and cleared that area. They just all moved into the suburb. Of course some 12 months later they remain in the suburb and the park area has been re-populated."

Jenny writes: "A very large, fat bunny (probably pregnant) and her little one are frolicking on my front lawn in suburban Turramurra. More next door. They are everywhere in the leafy north shore and I think that the preponderance of hedges provides perfect conditions."

"Rabbits are clearly out of control," writes Arthur. "Cutting research money for rabbit control and other environmental pests is both irresponsible and negligent. The Labor Party acts as though nothing west of the dividing range matters. The reason is obvious when you look at how many seats are held by the government in electorates west of the dividing range."

Chris writes: "It seems rabbits are the gossip topic at the moment in our social circle. They eat everything in sight and don't seem bothered by the close proximity of people or even dogs. The national park next door has been fox baited so now there are no predators. Perhaps a bounty in their heads like the good old days?"

"The rabbit explosion is frightening," writes Genevieve. "I live in Rosebrook (south west Victoria near Port Fairy). The rabbits line the roadside vegetation areas like they have tickets to the bloody Grand Prix."

Mike writes: "I was raised on a mixed farm in the Central West in the 1950s, back when rabbits arrived like an invading army. We had burrows under the house, paddocks moving with grey backs, and grass that vanished faster than a government funding program. Back then, we didn't have pipeline strategies or stakeholder engagement. We had Scouts. They came out for what was politely called a rabbit drive. Thousands of rabbits were funnelled into fencing corners and, shall we say, humanely but decisively removed from the future gene pool. It wasn't pretty, but it was effective - and nobody waited five to 10 years for a feasibility study."

"I live in the suburb of Griffith, ACT; daily hares on our street, also foxes regularly," writes Julia. "Almost 'domesticated' - early morning, hare sitting on my front pavers looking at me through the kitchen window and one evening; a fox standing in the middle of the street barking, not in the least bit perturbed by me outside looking at her. If the ACT government were interested in business development, it could help someone set up an iconic business in the capital - akin to Akubra!"