Missions to Mars: In search of life on the Red Planet

Going to Mars is non-trivial, since both planets revolve around the Sun and are hence in constant motion relative to each other. Earth and Mars are at their closest distance relative to each other every 26 months — and this is when Earthlings try to send missions to Mars.

Every two years since the 1960s, different space agencies have sent missions to Mars. Between 1976 and 1992, many launch windows remained unutilised. On occasion, there have been multiple missions in a launch window.

But never in history have three space agencies headed to Mars in a single launch window. And never in history have so many space agencies simultaneously operated a mission to Mars or the orbit of Mars. There are currently 10 spacecraft from five different space agencies — the United States, European Union, India, China, and the United Arab Emirates — either orbiting or on the ground on Mars. Two more rovers — NASA’s Perseverance and China’s Tianwen-1 — are set to land on Mars on February 18 and in May 2021 respectively

NASA has a lander (Mars Insight), a rover (Curiosity), and three orbiters (Mars Reconnaissance Orbiter, Mars Odyssey, MAVEN); India has an orbiter (Mangalyaan-1); the EU has 2 orbiters (Mars Express and ExoMars Trace Gas Orbiter); and China and UAE will have an orbiter each (Hope and Tianwen-1 respectively).

The flotilla of missions represents the spread of planetary exploration in general, and Mars exploration in particular. This is attributable to a reduction in launch costs and the cheaper availability of the technology required in space exploration.

The UAE’s mission of Hope

Two out of the three missions launched for Mars last July are already operational. The UAE, a tiny but rich country of <10 million people, bedazzled the world by becoming the fifth national space agency (after the US, EU, Russia, and India) to reach Mars when the Hope Orbiter underwent orbital insertion on February 9. The UAE beat out China in the race for Mars, albeit by a day.

The UAE mission will study the Martian atmosphere, and will seek to address the billion-dollar question of how and why Mars lost its atmosphere. The loss of the atmosphere resulted in the loss of surface water, and possibly the environment hospitable to life

The Chinese experiment

The Chinese National Space Agency arrived at Mars with lessons learned from a successful string of Chang’e missions to the Moon. Notably, the Chang’e 4 rover was able to survive more than 25 lunar nights (each night stretches to 14 Earth days) — this is a remarkable engineering feat, since temperatures can go down to –170 degrees C. The Chang’e 5 mission was able to successfully bring back rock samples to Earth in December 2020.

Tianwen-1, the first mission to Mars from China, successfully underwent orbital insertion on February 10. Tianwen-1 carries an orbiter, a lander, and a rover. China’s approach for landing a rover is somewhat different. Unlike NASA rovers, Tianwen-1 will orbit Mars for a few months before attempting to land in May this year.

The spacecraft has a suite of instruments to address a range of scientific questions. Interestingly, it has a ground penetrating radar instrument to look for water under the Martian surface. The rover is scheduled to land at Utopia Planitia, a location with possible ancient groundwater deposits.

Perseverance

The most sophisticated mission from an engineering standpoint, NASA’s Perseverance Rover, is en route to Mars, and is set to land at Jezero Crater, which was likely filled with water in the past.

Perseverance is NASA’s 4th generation Mars Rover — starting with Sojourner from the Mars Pathfinder Mission in 1997, followed by Spirit and Opportunity from the Mars Exploration Rover Mission in 2004, and Curiosity from the Mars Science Laboratory in 2012.

The goal is to look for bio-signatures in the dried up lake bed at Jezero Crater. The thought is that early life on Mars may have resembled early ocean-dwelling life on Earth, like stromatolites. If indeed this was the case, Perseverance would find fossils or some bio-signatures — hints of life — in either the chemical measurements or morphological observations.

In addition, Perseverance will produce oxygen on the Martian surface for the first time, using atmospheric CO2 from the Martian atmosphere. Perseverance will cache rock samples that will be returned to Earth by a subsequent European Space Agency/NASA mission.

Mangalyan 1

The Mars Orbiter Mission (MOM), commonly referred to as Mangalyaan-1, is a space probe launched by the Indian Space Research Organization (ISRO) on November 5, 2013. The indigenously-built space probe, which is India’s first interplanetary mission, has been in the Martian orbit since September 24, 2014. The mission which is aimed at studying Martian atmosphere helped the ISRO to enter the elite group of space agencies including the Soviet Space Program, NASA and the European Space Agency to reach Mars. India is the first Asian nation to reach the Mars orbit and the first in the world to achieve it on its first attempt.

MOM was launched aboard PSLV C-25 (an XL version of the PSLV), one of the world’s best and reliable launch vehicles. The spacecraft is based on the modified I-1-K satellite bus of ISRO which proved its reliability over the years in similar missions like Chandrayaan-1, the IRS and INSAT series of satellites. It carried 850 kg of fuel and 5 science payloads including a Mars Color Camera (MCC) which it has been using to study the Martian surface and atmosphere since entering the orbit successfully.

The spacecraft is tracked by the Indian Deep Space Network (IDSN), located near Bengaluru and complemented by NASA-JPL’s Deep Space Network. MOM showcased India’s spacecraft building, rocket launch systems and operation capabilities. The mission’s primary objective is to develop technologies required in planning, designing, management and operations of an interplanetary mission.

The secondary objective is to explore Martian surface features, mineralogy, morphology and atmosphere using indigenous scientific instruments. Initially planned for a lifetime of 6 months, ISRO extended the mission to another 2-3 years in April 2015 because of the adequate quantity of fuel still left in the spacecraft.

A decade of Mars missions

As the decade starts up, multiple missions are on the drawing board: prominently, the ESA ExoMars rover mission to return rock samples from Mars, ISRO’s plans for Mangalyaan-2, and the Chinese Space Agency’s plans for Tianwen-2 that will return rock samples from Mars.

In addition, there will likely be multiple flights of SpaceX’s Starship, first with cargo and finally with astronauts. In the history of humankind, 2020 will be remembered for the Covid-19 pandemic, but the 2020s may well be the decade of a flurry of spacecraft missions to Mars, ending with the first human footsteps on Martian soil.