Note : This story is published in CSIR-NISCAIR’s prestigious magazine Science Reporter in April 2021.
What if there is NO AIR on Earth?
What if there is NO ATMOSPHERE on Earth?
What if harsh SUN RAYS and SOLAR WINDS reach us directly?
These questions can give you nightmares.
There is a two word answer to all such questions
But science never says ‘NO’. Experts look forward to opt for multi planetary system. So, if not Earth, where can we go? Scientists and Space agencies are working hard to find Life beyond Earth, which is believed to be possible on our nearest neighbour – Mars. But according to recent research and studies there is air problem on Mars. Mars is losing parts of its atmosphere, rather Mars has At’loss’phere.
Just push a rewind button in your minds to count the number of missions sent to Mars till date. From first successful mission to Mars in 1965 to the latest few in 2021, missions from various space loving countries are being sent. February 2021 saw three space missions, Emirates Hope Mars mission, China’s Tianwen-1 mission and NASA’s Perseverance Rover reaching the Red Planet. Purpose of any such missions is studying Mars and to be specific ‘Life on Mars’. Private companies aim to reach mars in next few years, build colonies there, and sustain life forever. Space X owner Elon Musk said once that “If humanity doesn’t land on Mars in my lifetime, I would be very disappointed.” NASA says the first humans will set foot on mars in mid 2030s. No doubt it will be the most dangerous mission any human has ever taken. SpaceX’s first crewed mission to Mars could come as early as 2026. But…
The story changes from here on. Now issue is not that how do humans get on Mars, but the question is how do we survive once we could land on the Red Planet. It is just like standing under the dark sky, counting stars and imagining looking up at Mars, wondering about life surviving there.
The atmosphere of Mars is much thinner than Earth’s. It is 95%-97% carbon dioxide, 3% nitrogen, 1.6% argon, and less than 1% oxygen, carbon monoxide, water, methane, and other gases, along with a lot of dust. Mars atmosphere is colder than Earth’s. Owing to the larger distance from the Sun, Mars receives less solar energy and has a lower effective temperature, which is about minus 63 degrees celsius.
Life on Mars has been a favourite topic for 70 mm screen since the black and white days. And recently a movie called Martian depicted an astronaut’s lone struggle to survive on Mars… He not only successfully survived but also grew potatoes there, symbolically depicting possibility of life of Mars. There is a twist brought to this story by a team of scientists from Indian Institute of Space Education and Research (IISER), Kolkata with their latest research.
How the research was done ?
Mars, which is now 4.6 billion years old, is believed to have once hosted an intrinsic magnetosphere due to a dynamo in its interior. Magnetosphere is invisible magnetic field lines which is generated by a magnetic dynamo. These magnetic field lines envelope mars like an umbrella and protects mars atmosphere from the solar plasma winds. The solar plasma winds made up of electrons and ions, travel at a high speed of 400km/sec.
The researchers from Center for Excellence in Space Science India and Department of Physical Sciences of Indian Institute of Space Education and Research (IISER), Kolkata model a Mars-like planet interacting with plasma wind from a Sun-like star. They have used 2 simulations to explain that Mars has lost its magnetosphere and in turn some of its atmosphere. IISER Scientists behind this very extraordinary research Prof. Dibyendu Nandi and Dr. Arnab Basak have demonstrated the complex interplay of processes that resulted in the Sun’s strong plasma winds eroding away Mars’s atmosphere.
Scientists have developed 2 distinct computational models depicting 2 different scenarios.
Prof. Dibyendu Nandi describes the models as – “The computer models we have developed can simulate the space environment of planets and will guide and support space missions to other solar system planets. We can also use these models to understand why some planets can host life and other planets cannot. We are happy that after many years of research at the Center of Excellence in Space Sciences India at IISER Kolkata, we have been able to develop these capabilities which were not earlier available in India.
First model had young Mars with its magnetosphere intact. Then solar plasma winds were introduced in mars atmosphere. These plasma winds have their own magnetic field. It was observed that when mars had magnetosphere, it acted like a protective shield which could stop the solar winds from reaching martian atmosphere and protect it from any kind of disruptions.
In the second simulation, Mars is without intrinsic magnetosphere. This time again the solar plasma winds were introduced. These plasma winds have their own magnetic fields which is believed to directly impact the mars atmosphere and took it away in bits and pieces. It was a kind of erosion by solar plasma winds. This is called the Planetary Atmospheric Erosion and confirms the long held belief that magnetosphere of the planets play a crucial role in sustaining their atmosphere. Alternatively, like Mars, planets that lose their magnetic field eventually become inhospitable with loss of their atmosphere. Thus present day Mars is a barren land, only having a thin, dry atmosphere made mostly of carbon dioxide.
Research Scientist at Center of Ecxcellence in Space Sciences India, Dr. Arnab Basak explains “Our model explores the interaction between the solar wind and planets with different magnetospheric strengths. We found that the solar wind is able to penetrate closer to a planet with weak intrinsic magnetosphere, leadinarnabg to greater atmospheric loss. When the primitive Mars lost it’s global magnetic field, an imposed magnetosphere formed around the planet due to the draping solar field lines but it was not so efficient in shielding the atmosphere, leading to it’s heavy erosion and making Mars uninhabitable. For present Mars-like conditions, the simulation shows good agreement with spacecraft observations from Mars Global Surveyor (MGS) and Mars Atmosphere and Volatile EvolutioN (MAVEN) missions and is expected to complement data from the recent Mars missions.”
Both the Scientists even helped us identify some of the highlights of the research…
1. Mars lost its intrinsic magnetosphere around 4 billion years ago due to the halting of its dynamo.
2. The Martian atmosphere was exposed to the bombarding solar wind particles resulting in erosion of a significant portion of the atmospheric matter over time.
3. Our model shows that as the planetary magnetosphere weakens, the impinging solar wind causes greater atmospheric loss.
4. An imposed magnetosphere is formed around the non-magnetised planet (present-day Mars) but is not as effective in blocking out the solar wind plasma.
5. The study is relevant for the detection of habitable planets in exo-planetary systems and hopes to aid future missions.
Dr. A S Kiran Kumar, Former Chairman of Indian Space Research Organisation (ISRO) assures that Magnetic field is highly important for our survival on any planet. If a planet is not protected with the magnetic field, the solar winds, the particles, etc. can be highly damaging. The speed of the coronal mass ejection is very high, which cannot only impact the surface but high speed can even take away the useful gases, particles, etc. from the Mars atmosphere leading to a void. He also points out that Mars atmosphere is a fraction of Earth’s atmosphere. He is very hopeful that our universe has billions of solar system, so how is it possible that there is life only on earth.
Earth can suffer At’loss’phere ?
In case of Earth the intrinsic magnetic field of Earth creates a huge magnetosphere, which spans ~10 Earth radii from surface, shielding the upper atmosphere of Earth from solar wind erosion. But since Mars does not have a global (intrinsic magnetic field) like Earth, the solar winds come too close to the planet, say around 250-300 Km from surface, and hence erodes the upper atmosphere or exosphere of Mars. Later due to some unknown reasons Mars has lost its magnetosphere, may be because of dysfunctioning of the dynamo.
Along with the magnetosphere, gravity is another strong point that holds the atmosphere. If Earth’s dynamo is working properly in the liquid outer core and generating magnetic fields, this surrounds the atmosphere and makes the protective shield around the Earth. But, somehow if the dynamo action is stopped due to non spinning of Earth or solidification of liquid outer core, the magnetosphere will collapse in a time scale of something like two hundred thousand years and our atmosphere will be exposed to solar winds. Thus, leading to erosion of our atmosphere and ultimately loss of atmosphere.
Curious case of ‘Life on Mars’ ?
Various missions sent on Mars are orbiting mars and remotely mapping and imaging its surface. They are trying to solve the mystery of mars atmosphere. They are trying to find reasons about atmospheric mass loss. There are several future missions planned to Mars, including India’s Mangalyaan-2 orbiter which is set to launch in 2024. SpaceX CEO Elon Musk has indicated that humans could fly to Mars within the next decade.
Factors like the existence of a moderately warm, moist atmosphere and liquid water determine whether a planet can host life. Then how will we survive on mars? How colonies can be planned on Mars? Human survival on Mars would require living in artificial Mars habitats with complex life-support systems. Creating artificial environment with the help of solid barriers is the key that will prevent solar winds and cosmic energetic particles from entering the artificial atmosphere.
Even creating artificial magnetosphere is possible with Gen-X technologies. By reverse engineering the process of running fans inside your homes, where you need electricity which contains electromagnetic field, magnetosphere can be created on a planet. It is a complex process where electricity induces energy in the coils of the fan which in turn rotates it. Reversing this process, we can generate electricity by rotating giant fans or something similar making a dynamo that generates electromagnetic forces. The magnetic field generation can be induced to create artificial magnetic field around the planet which is also knows as magnetosphere.
This way, just like artificial biosphere, artificial magnetosphere can be made where you will be protected and colonies can be made. We just need to improve technology. This seems impossible but for the scientists all over the world, nothing is impossible. So if we want to survive on Mars, we need to bring back the Mars which existed millions of years ago.
How do we survive on Mars ?
It is not easy to imagine how humans would survive on Mars. Life is one which knows how to survive, evolve and sustain. It all boils down to the Darwinian concept of “Survival of Fittest”. Mutation can also help us survive in tough conditions. Humans by nature are explorers, inventors and discoverers. There are ways in which humans would make them survive on Mars, much beyond what we can imagine now. But, with our current knowledge also, humans can survive.
Director of Physical Research Laboratory Dr. Anil Bhardwaj quotes – “The condition on Mars may be extreme and difficult for life to survive but we still find life on Earth surviving in harsher condition and hence finding life on Mars may be challenging but not impossible.” When asked if Mars atmosphere can be made breathable for life to survive? He replies – “The Carbon dioxide present in atmosphere can be broken into oxygen and with ample sunlight, plants can grow in controlled environment which can further convert Carbon dioxide into oxygen and make the environment more human friendly. However it may take from thousands to millions of years, like it happened on Earth.”
He is also concerned that – “Rather than physical, more difficult question would be social and psychological, and above that time-delay of signal in communication. It may take 10 to 40 minutes for getting response from humans on Mars, depending on where Earth and Mars are in their orbit around Sun. So, things would be complicated and in this fast world of internet, we may have to think of messages coming by post, rather than email.”
Mars and Earth have approximately the same landmass.
Mars is much colder than Earth due to its greater distance from the sun.
Mars has only 15% of the Earth’s volume.
Mars has just over 10% of the Earth’s mass.
Martian surface gravity is only 37% of the Earth’s.
The carbon-dioxide-rich atmosphere of Mars is also about 100 times less dense than Earth’s on average.
On Mars the Sun appears about half the size as it does on Earth.
Earth’s surface is covered by liquid water. Where as Mars now has no liquid water on its surface and is covered with bare rock and dust.
Mars is home to Olympus Mons, the tallest mountain in the solar system.
Mars has the largest dust storms in the solar system.
Mars is called Red Planet because its iron-rich dust gives its landscape a rusty-red colour.
Sunsets on Mars are blue.
A Mars year lasts 687 days.