Life beyond the blue planet: The Extraterrestrial

Given the size of the universe - there are at least 100 billion stars in our home galaxy alone and perhaps 100 billion galaxies of much the same size scattered throughout deep space - few scientists believe that the Earth is the only home of life. But until quite recently, the field of exobiology - the study of extraterrestrial life also known as astro-biology - was almost moribund. It could come up with some interesting speculations but that was about all.

The most vital 'exobiology' discoveries, though, were made right here on Earth. Biologists have learned that life is much more robust that most scientists believed 30 years ago. Earth micro-organisms have been found thriving in astonishingly hostile environments. Deep beneath the oceans, for example, near the volcanic vents known as black smokers, some microbes grow and multiply at temperatures above 110 degrees - according to some scientists, perhaps as high as 170 degrees.

The concept of alien-life forms has always intrigued us

Life is just chemistry done correctly

While life is a special kind of complex chemistry, the elements involved are nothing special: carbon, hydrogen, oxygen and so on are among the most abundant elements in the universe. Complex organic chemistry is surprisingly common. Amino acids, just like those that make up every protein in our bodies, have been found in the tails of comets. There are other organic compounds in Martian soil. And 6,500 light years away a giant cloud of space alcohol floats among the stars.

Habitable planets seem to be common too. The first planet beyond our Solar System was discovered in 1995. Since then astronomers have cataloged thousands. Based on this catalog, astronomers from the University of California, Berkeley worked out there could be as many as 40 billion Earth-sized exoplanets in the so-called “habitable zone” around their star, where temperatures are mild enough for liquid water to exist on the surface.

There’s even a potentially Earth-like world orbiting our nearest neighbouring star, Proxima Centauri. At just four light years away, that system might be close enough for us to reach using current technology. With the Breakthrough Starshot project launched by Stephen Hawking in 2016, plans for this are already afoot.

Robust life forms can give some answers

The existence of these so-called extremophile organisms radically changed our view of what might be called "the necessities of life". Extremophiles live happily without sunshine, without moderate warmth, without organic molecules to feed off and with no need for photosynthesis - many digest raw minerals and fuel themselves with basic chemical reactions.

Many share another fascinating characteristic, too. The genetic code of these creatures suggests that they are not recent adaptations that have moved away from 'mainstream life' into awkward niches shunned by their competitors. Instead, in evolutionary terms they are among the oldest living things on Earth - probably among the very first to appear.

The implications for life elsewhere in the solar system are huge. We know now that all life needs is liquid water - even a little dampness will serve - and some kind of energy source. Exobiology is back in business.

Mars remains the best candidate for the breakthrough discovery of an extraterrestrial organism. In the early solar system four billion years ago, it may well have offered better prospects for life than the Earth. In 1998, NASA scientists found what may have been fossilised ancient Martian bacteria in a meteorite blasted from the planet's surface by a cosmic impact; the Mars rock drifted through space for millions of years before eventually crashing down in Antarctica.

Exobiology will be a major element in the Mars missions of the first half of the 21st century. ESA's Mars Express arrived in Martian orbit in December 2003; the Aurora Programme is looking at plans for a sample return mission and even a human visit. Some of Earth's Antarctic life-forms could probably live on Mars today. Perhaps below the Martian surface, the corresponding native organisms are just waiting to be discovered.

Europa, ten times more distant than Mars, is a more difficult proposition. But plans for Europa missions are on the drawing board, too. Exobiologists no longer restrict themselves to planetary environments. Comets, for example, are rich in organic material and certainly could be colonised by some kind of extremophile. Some theorists even think that life originated first in a cometary environment then reached Earth and, perhaps, other planets.

Probes we have sent to other planets help us study the scope of life there

Imagination Corner -Impact of Alien attack

This one is less ideal, though highly likely if sci-fi movies are anything to go off. Long story short, the aliens come to Earth, most likely in massive warships that blow up our major cities. Without superheroes or Autobots to save us, the Earth, and humanity, perishes under the power of these ruthless aliens.

After the initial attacks, we imagine exchange markets would go into meltdown as people start panicking, preferring to spend their final moments with loved ones instead of trading international currencies. Should the aliens decide to attack one country first (always the USA as per Hollywood), the value of their money would rapidly decline in response. While this sounds good, we can guarantee no one would be travelling to the USA to take advantage of a discount Disney trip. If you get in quick, you might be able to get in a cheap amazon order, but I wouldn’t bet on it arriving in India in one piece.

As the aliens took over the planet, our government and economic systems would fail to operate. This would potentially push any remaining humans into economic depression (probably also emotional distress due to the whole alien invasion thing). Currency would cease to exist as we know it, as the aliens integrate their own type or simply move to a trade-based economy.

Usual belief among people is that aliens would be obsessed with probing humans upon their arrival to Earth, and  I’m putting my money as well on the fact that there would definitely be some kind of probing involved in this scenario. 

In case you come across aliens, just run for your life

This situation is not ideal in anyone’s books, so here’s hoping the aliens are gracious when they come to Earth and instead lean more towards scenario two.

That's it for now. Stay healthy. Stay Safe.