Top 5 Extraterrestrial Life Facts

Let’s just Hope they’re friendly. There is methane and water–albeit in the form of ice and vapor–on Mars, which are big flags when it comes to the possibility of life. Many organisms produce methane, and water is needed for the survival of every organism we know of. While these chemicals do not necessarily mean that there is life on the planet they do hint at it–even if that life is microscopic in size. Also, the planet is riddled with caverns many of which contain pockets of lava. If life were to exist on Mars it would probably be found under the planet's surface and near one of these nice, warm lava pockets. The planet's crust would work to protect against most solar radiation and the lava would provide heat and energy in much the same way that volcanic vents create ecosystems at the bottom of earth Oceans. If life isn’t on Mars, then there’s a good chance we’ll never find it. The nearest solar system that has earth-like planets is almost 5 lightyears away, and it would take about 40,000 years for us to travel there with our current technology.

We detect the existence of many planets not by seeing them, but by studying the dimming of light as they transit in front of their host stars. We can calculate many things about a planet by examining this light absorption. We can learn things ranging from the planet’s surface temperature, to its size and density. Using this information has helped us to detect dozens of planets that have the potential for life. A paper published in the journal Astrobiology claims that the best way to make contact with intelligent life would be to assume that other planets are watching us in this same way, and to point our radio receivers and transmitters towards our transit zone which is the thin slice of space where we would be most detectable through this method. The paper’s authors say this would be lightyears better than our current system of pointing radios in random directions and crossing our fingers.

Radios might not even be the best way to find aliens. We've been using Radio signals less and less over the past few decades and if aliens exist they might also be using methods to communicate that don’t involve radio. One new idea to look for ETs is by searching for the lights from alien cities. We know that cities like Tokyo can be seen as far away as the Kuiper belt using only telescopes, and we can calculate the amount of light that should be on the dark side of planets that are much farther away than that. Unfortunately, with our current technology, an alien city would have to put out about ten times more light than Tokyo. But, hey! Maybe aliens will give us better technology and we can use it to find th– nevermind.

When we think about which planets might have life, we mostly look at planets that are similar to earth. These are planets that are close to their sun (but not too close) and have plenty of hydrocarbons. But what if the extraterrestrials are not built out of the same things as us at a molecular level. Maybe life can develop with a silicone base, or maybe it can develop without water. This is where bodies like Titan come in. Titan is one of Saturn’s moons and it is nothing like earth. The average temperature of the planet is about -17 degrees Celsius. And the water that exists there is frozen as hard as stone and unusable by any life. What Titan does have is an abundance of methane, which, while it would be gaseous on earth, is liquid at the cold temperatures on Titan. These liquids could be the building blocks of strange alien life that would be unimaginably weird from our perspective. Like really weird. Like the ending of 2001: A Space Odyssey weird.

It is possible that the background radiation of the cosmos can cause life to spontaneously develop in the vacuum of space. I mean, if cosmic rays can make Jessica Alba and Kate Mara invisible, who knows what else it could do? Laboratory tests have shown that when water, methanol, and ammonia react with ultra violet radiation they can develop into a variety of different sugars including some of the parts of RNA. All of these elements commonly float around in clouds in the depths of space, and lab tests have shown that these reactions can even occur at temperatures as low as those in outer space. Granted, if these organisms can exist they must be very simple because the radiation of space is just as likely to destroy DNA as it is to create it. But it does mean that the building blocks for complex life could be in abundance throughout the universe. Moreover, some astrobiologists believe that these rudimentary life forms could further evolve on volcanic planets that don't even have access to suns, and these “rogue plants” could be all over the place. Rudimentary life forms might exist in trillions and trillions and trillions of surprising places.

So what do you think? Will we ever find even the most basic form of alien life? For trillions and trillions of top 10s and silicone based top 5s, be sure to subscribe to WatchMojo.com