Mars is no longer the tentative dream from an H G Wells novel; it is the very real destination of the 21st century, in the crosshairs of Elon Musk and Jeff Bezos. The onus is shifting from scientific exploration and mapping of Mars to first, returning a sample from Mars; two, flying humans to Mars; three, setting up a base on Mars; four, extracting water and oxygen as preparation for a human landing and, finally, searching for primordial forms of life on Mars.
A sea change has taken place in the landscape of Mars Exploration, since I first stood in NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California, to watch the Mars Pathfinder spacecraft land on Mars 21 years ago. At the time, there was serious scepticism on whether one could land on Mars for less than the cost of a Hollywood blockbuster, a tenth of the cost of the previous Mars lander. Very little was known about Mars, including the presence of water in the frozen form.
Twenty years later and a half of dozen-plus missions wiser, we know a lot about Mars, its climate, its topography, its water-rich history, the distribution of water ice at present, atmospheric patterns, and dust storms. Multiple Mars missions from orbiters to rovers have operated on Mars for multiple years — at times, even as simultaneous observation outposts on Mars.
On the engineering and financial fronts, there has been an even drastic change. A manned mission to Mars was always thought to be prohibitively expensive, perhaps of the order of $500 billion or beyond — a price tag unthinkable for any single space agency or for all space agencies collectively. In other words, sending a human to Mars remained a distant economic dream. But this dream transformed into a roadmap after Elon Musk presented an ambitious but plausible plan for taking humans to Mars — which cut costs to about a millionth through a combination of using reusable launch vehicles, by refuelling the spacecraft in space, by generating fuel on Mars for the return journey, and by designing a spacecraft that could carry ~100 passengers. Musk’s plan could bring the cost per passenger down to the median cost of buying a house in the US — or around $200,000.
From an engineering perspective, the plan is difficult but immensely plausible. The design for the launch vehicle to be used, BFR (or Big Falcon Rocket) by SpaceX is under way, the target is to fly around the Moon using the BFR in 2023, and the first tourist has already signed up for this maiden trip. A firm architecture for a manned mission to Mars seems to be falling into place. The financial backers of SpaceX have stood steadfastly with the Mars Roadmap, and the valuation of the private company is said to be north of $25 billion.
The InSight lander was expected to arrive at Mars around 1 am IST Tuesday, making a soft precision descent on Elysium Planitia, a plain near the Martian equator — NASA’s first attempt to land on Mars since Curiosity in 2012.
The significance of Mars InSight is that it is going to provide, for the first time, a seismic monitoring station on Mars that can monitor Marsquakes, decipher the interior structure of Mars, and detect large meteorite impacts on the planet. Also, for the first time, underground heat flow measurement from InSight will help model the thermal evolution of the interior of Mars over the last 4.5 billion years, getting a window on fundamental questions like the state of the mantle and the core of Mars.
Equally significant, InSight is flying MarCO, a couple of CubeSats, for the very first time in deep space as a technology demonstration exercise. CubeSats are miniature satellites, can be built from commercially available hardware by amateurs and, most significantly, cost a hundred or a thousand times less than a spacecraft mission. If CubeSats can be used to send useful data about other planets or about outer space, the cost of exploration of near Earth planets and satellites would decrease dramatically. But in spite of all the positives, Mars remains a difficult human aspiration.
First, a frontier opens up when there is a business model, and at present, there is none. SpaceX would like to fly space tourists, but no one knows whether there is a larger mass market for space tourism as opposed to the occasional rich space tourist. Second, the distance is what makes the human journey so difficult. By the time of landing, Mars InSight would have travelled ~7 months and covered a stunning 300 million miles — or about 30,000 times as far as New Delhi is from New York. In comparison, the Moon is just 3 days and a quarter million miles away. The huge distance challenges the extremes of what is possible — in terms of cost, in terms of endurance of the human body, and in terms of how far the human spirit dares to dream.