Since time immemorial, the very possibility of finding ‘intelligent’ life on other planets within and outside the solar system has stoked our imaginations. Every part of our lives, be it movies, television or even the books we read amaze us with space adventure, how in life in space(Mercury, Mars, Venus, moon) would be and what it would be like to find an extraterrestrial life away from Earth!
Thanks to government-funded massive space explorations, Earth observatory readings and years of research, we are now very close to finding it somewhere else in the solar system or other exo-planets found beyond it. NASA believes that we could discover aliens within the next 10 to 20 years!
How do we know that there is possibly life out there?
Millions of observations from interplanetary probes, the Hubble telescope and Earth-based experiments (LiGO) hint at the evidence of water and nitrogen throughout the Milky Way (the Earth is a part of this galaxy) along with the other organic molecules which are necessary for sustaining Earth-like life
At present the only planet capable enough to support life in the solar system is Earth, but explorations to the moon like the Chandrayaan-1 have found traces of water on the Moon as well! On Mars, scientists do believe that we can make the planet habitable with custom habitats (HABs) as you may have seen in the Martian movie.
What about the solar system? Is life out there?
There are eight planets in the solar system (yeah, Pluto is now considered a dwarf planet in the Kuiper belt, a ring of bodies beyond Neptune) and an untold number of moons that may have/support existence on them. Let’s take a look at our solar system and see what is habitable and what isn’t:
Mercury
Mercury is the deepest and smallest planet in the Solar System. Since Mercury has a really thin atmosphere of oxygen, the Sun can vaporize any kind of life forms trying to form on its surface. It is highly unlikely for us to find any kind of life-forms deep inside its dry surface.
Venus
A day on Venus is more than a year and Venus is the second brightest star in sky during the night. Venus is within the Goldilocks Zone (the area of space which is neither too far nor too close to the Sun and is suitable enough to host life), however, the Soviet Union’s Venera probes found that the planet has a blistering hot sulphuric atmosphere which simply cannot host life due to its highly toxic nature.
On Earth, life forms known as Extremophiles do live in extremely hot atmospheres near the Earth’s crust, but on Venus, the toxicity of the planet’s gases makes life uninhabitable.
Earth’s Moon
The Moon has no atmosphere of its own which is why haven’t yet found any life that could have ever existed on the planet. However, the possibilities of finding life haven’t ended. The Chandrayaan-1 built by Indian space agency ISRO, discovered traces of water beneath the Moon’s surface and since the Moon was created by a planetoid that smashed into the early Earth, there may be life on the Moon, but we are still yet to find it. Chandrayaan-2 was recently launched by ISRO which had a hard landing on the moon.
Humans can live on the moon, but we would have to create artificial habitats there to shield us from cosmic radiation and asteroids from the Jupiter-Mars asteroid belt hitting the moon every now and then. Very soon, the Moon will beam 4G network to the Earth via satellites and mirror technology; if Humans inhabit the moon, at least we will have great internet connectivity there!
Mars
Mars also has no atmosphere like Mercury, but it has ice caps on its north and south poles, which are suspected to have bacterial life trapped inside them. New findings from NASA’s Mars Reconnaissance Orbiter (MRO) provide the strongest evidence yet that liquid water flows intermittently on present-day Mars.
Furthermore, some scientists speculate that Mars may have harboured life in the past, but has lost its ability to support life since it does not have a magnetic field anymore which makes any life forming on it susceptible to the Sun’s cosmic rays. If we wish to live on Mars, (as being planned by SpaceX) we would have to build living quarters there in the form of HABs which is basically called terraforming on a planet.
Since Mars is also part of the Goldilocks Zone, it could’ve supported life at one point in time. Now, it is a cold planet, so if we plan to live there, we have to visit the planet when it is much farther from the Sun during its orbit. Life could also be on the two moons of Mars called Deimos and Phobos, which were once asteroids that flew too close to Mars, but got pulled into orbit around the giant red planet.
Asteroid Belt
The asteroid belt is the circumstellar disc in the Solar System located roughly between the orbits of the planets Mars and Jupiter. It is occupied by numerous irregularly shaped bodies called asteroids or minor planets. None of these has been proven yet to be able to sustain life. About half the mass of the belt is contained in the four largest asteroids: Ceres, Vesta, Pallas, and Hygiea. Scientists believe that there is some amount of water vapour on Ceres but not enough to sustain life on it.
In the next article, we’ll take you beyond Mars and reach the other planets and moons in the solar system!
Read also: Life in and beyond the solar system? Imagining the possibility– Part 2