ASTROBIOLOGY

THE SEARCH FOR LIFE IN THE UNIVERSE:

Are we alone? is life on our planet the only example of life in the universe? if not, then how and where should we look for other intelligent beings. 

To answer all these questions came into being a new subject called "ASTROBIOLOGY".

LIFE IN THE UNIVERSE:

From the Big Bang to the evolution of intelligence and culture, the universe has evolved from simplicity to complexity. we are a result of an incredibly complex chain reactions that spanned billions of years.

Life on earth depends on just few simple molecules, is that the same case for the other intelligent beings out there on exoplanets? Nucleic acids may not be the only biomolecules capable of coding for life processes , Mind it .

LIFE ON EARTH:

The surface of the young earth is a very violent place. Natural radioactivity, lightning, volcanism, solar ultraviolet radiation, and meteoritic impacts all provided large amounts of energy that eventually shaped ammonia, methane, carbon dioxide, and water into more complex molecules like amino acids and nucleotide bases that are the building blocks of life as we know it. 

AMINO ACIDS build proteins and proteins regulate metabolism for daily living 

sequence of NUCLEOTIDE bases form gene parts of the DNA and hence determine the character of an organism

AN INTERSTELLAR ORIGIN:

Recently a dissecting view has emerged. Some scientists argue that there may not have been sufficient energy and raw materials for the reaction to occur in a significant rate in any case. Instead, they suggest, most of the organic material that combined to form the first living cells was produced in interstellar space and subsequently arrived on the earth by meteorites and comets.

DIVERSITY AND CULTURE:

Now let's imagine the entire lifetime of  earth to be 46 years rather that 4.6 billion years.

On this scale we have no reliable existence. Life originated at least 35 years ago, when the earth was about 10 years old. Our planet's middle age a large mystery. Not until about 6 years ago did abundant life flourish in the earth's oceans. Life came ashore about 4 years ago, plants and animals mastered the land only 2 years ago. Dinosaurs reached their peak only six years ago, only to die suddenly 4 months later. Humanlike apes changed to apelike humans only last week, and the latest ice ages occurred only few days ago. Homo sapiens did not emerge until 4 hours ago. Agriculture was invented within the last hour, and the modern science is just 3 minutes old. 

LIFE AS WE KNOW IT:

Let us begin by asking, might earth-like life exist(or have existed) on some other body in our planetary system.

The Moon, Mercury, Venus cannot support life(recent studies suggest that it will support for the ) due to extremely hostile environmental condition where water cannot exist in liquid form and other such factors makes it difficult to live there.

A more promising scenario comes from the discovery of  the Jovian Moons, Jupiter's Europa and Ganymede, and Saturn's Titan and Enceladus may contain significant amount of liquid water.

The planet most likely to harbor life still seems to be mars. The red planet is harsh by the earth standards and liquid water is scarce, lack of magnetism and no ozone layer, but we should perhaps not be too quick to rule out an environment solely based on it's extreme properties

LIFE IN THE EXTREME:

In recent years scientists have discovered many instances of so called  "EXTREMOPHILES" - life forms which exist in very harsh environments the super heated hydrothermal vents 

                                             

                                                                       

 heated hydrothermal vents formed under the ocean

these environments are similar to those hostile conditions found on Mars, Europa, Titan, Enceladus, suggesting that life as we know it might well be able to thrive in these hostile, alien worlds.

So that's all for it buddy😀, comment your thoughts below