For centuries, people have been asking the question while looking at the countless stars in the night sky—are we really alone? Is there another species of life somewhere in the universe, searching for answers like us? Scientists are now embarking on a real search, going beyond the realm of imagination. One after another, space missions are underway to find out whether life exists somewhere within the solar system.

Mars: Was there once a sign of life?

Mars today is a dry and icy desert. However, NASA rovers have reported that there was liquid water on this planet in the past. And water means the possibility of life. The Curiosity and Perseverance rovers are collecting samples of Martian soil and rocks. These will be returned to Earth in the future through the 'Mars Sample Return' mission.

Amy Williams, a professor at the University of Florida in the United States and a NASA researcher, said, "We are looking into whether the Martian environment was suitable for the survival of microorganisms in the past."

Venus: Potential in an Extremely Hostile Environment

Although Venus is called Earth's twin, its surface is so hot and pressurized that it is almost impossible for life to survive. Also, thick clouds of sulfuric acid cover the sky. However, scientists say that some places in Venus' upper atmosphere are relatively tolerable, where extremely environmentally friendly microorganisms can live.

The MIT-led 'Morning Star' mission will collect samples from Venus' clouds and return them to Earth. In 2020, it was claimed that phosphine gas was detected in Venus' clouds, which indicates the possibility of life. Although this is controversial, the new mission will answer that question.

Enceladus and Europa: Oceans under the ice

Saturn's moon Enceladus and Jupiter's moon Europa—both satellites have found evidence of a vast ocean under thick ice. The Cassini mission has collected saltwater samples from Enceladus's fountains. Phosphate, an essential chemical element for life, has also been found there.
On the other hand, the gravitational pull inside Europa keeps the ocean liquid, which creates an environment similar to Earth's deep ocean. The European Space Agency's Jupiter Ice Moons Explorer and NASA's Europa Clipper missions will bring new information there in the coming decades.

Titan and Ceres: New Doors of Possibility

Saturn's moon Titan is said to be one of the most mysterious worlds in the solar system. It has a thick atmosphere rich in nitrogen and methane and a methane cycle. Scientists say that the chemical environment here could form the basis of life. NASA is planning to send an octocopter mission, which will collect samples from different regions of Titan.

On the other hand, the possibility of liquid water is also seen under the icy surface of the small dwarf planet Ceres, which could open the door to the existence of life.

Scientists' opinion

Although possible environments for life have been identified on several planets and moons, no direct evidence has yet been found. According to scientists, if life exists, it will be simple organisms like microorganisms. They are not able to communicate with us. Therefore, humanity must move forward in this search.