LIFE
ON VENUS:Possible or Not?
- By Simran
- Batch(2k19), Deptt. of Chemical Engg.
- BIT Sindri, Dhanbad
We are finding the existence of life on mars but have you ever thought of different planets too?
Let's venture upon it and analyse that whether Venus can harbour life or not?
Fig: Venus
in contrast-enhanced false colour
Let’s dive on further
It is a planet made up of rocks or metals with hard surface. It is
sometimes called Earth's "sister planet" because of their similar
size, mass, proximity to the Sun, and bulk composition. It is radically
different from Earth in other respects.
ELEMENTS FOR LIFE
Understanding how life formation had taken place on Earth will enhance our knowledge
about our origin. It has also provided insight into the key ingredients needed
for life.
Even today, details regarding origins of life on Earth is a mystery with
multiple juxtaposing scientific theories. In most of the cases these theories
have common set of environmental conditions necessary for life. These necessary
conditions are:
• Liquid Water
An essential element for life. It dissolves the molecules to facilitate their
channel reactions.
Even though there are other solvents (like methane) which has the potential to
support life, but water being universal solvent dissolves a huge range of
different molecules.
The observed escape indicates that water in Venus is being broken up (photodissociated ) in the its atmosphere ,and the free
hydrogen sweep into interplanetary space by solar wind.
• Mild Temperature:
Since Venus is shrouded by an opaque layer of highly reflective and suffocating
cloud made of sulphuric acid, it is
the hottest planet with temperature 464°C. The temperature being more than
122°C does not support life of complex organic molecules.
 |
Fig: Surface of Venus due from Venera
13 (picture taken from Roscomos via NASA)
Being curious to know, that how is temperature detected?
The temperature was measured in Venus' upper atmosphere by observing an infrared glow emitted by carbon dioxide (CO2) molecules
when they were energized by light from the sun. Infrared light is invisible to
the human eye and is perceived by us as heat, but it can be detected by special
instruments. In the research, it appeared as a line on a graph from a
spectrometer, an instrument that separates light into its component colours,
each of which corresponds to a specific frequency. The width of the line determines
temperature.
Also, Venus has dry surface with slab-like rocks spreaded over and periodic volcanic eruption.
• Traces of Phosphine gas:
Telescope has detected unusually high
concentration of stinky flammable chemical. Phosphine is a toxic gas comprising
of 1 phosphorus and 3 hydrogen atoms (PH3).
It has been detected at 20 parts per billion coming from 50 to 60 kilometres
from the surface, where the temperatures are not too hot, not too cold, but just
right for life. This gas raises the tanzaling possibility of something alive in
the planet. This gas in the planet
indicates the presence of bacteria which
survive in the absence of oxygen.
• Atmospheric Condition:
 |
Among the four terrestrial planets that are Mercury ,Venus ,Earth and Mars ,Venus has the densest atmosphere consisting of more than 96% carbon dioxide.
It was also speculated that there was presence of water ocean in the past but
it got vaporized as a result of increase in temperature due to greenhouse
effect.
The atmospheric pressure at the planet's surface is about 92 times
the sea level pressure of Earth, or roughly the pressure at 900 m
(3,000 ft) underwater on Earth.
It has unpleasant climate with an active Mesosphere and Thermosphere.
Fig: Cloud structure in Venusian
atmosphere
The Wind pattern result in altered local
temperatures and their variability over time due to solar heating and east to
west zonal wind.
• Seasonal Effect:
Earth experiences seasonal changes. This is because of the tilt of Earth about
23 degree, which changes the intensity of sunlight and length of the day in
each hemisphere each year.
While in case of Venus, it is tilted so much that it is almost upside down,
having a tilt of less than 3 degree. This results in negligible seasonal effect
in the planet.
On comparing with the adaptation on Earth the essential feature such as mild temperature, liquefied water, proper climate is not present in Venus. Although, with the discovery of phosphine gas, Venus has also joined among the planetary bodies where life may once have existed or may still do so today. There are many more about the planet to be known.
In parallel, there is now a huge opportunity
to carry out lab work to better understand the types of chemical reactions that
might be possible on Venus — for which we have very limited information at present.
ConversionConversion EmoticonEmoticon