Restless quest

The journalists listened to Ellen Stofan with growing excitement. NasaThe National Aeronautics and Space Administration, responsible for the US space programme.'s chief scientist had just made an amazing prediction: "I think we're going to have strong indicationsSigns. of life beyond Earth within a decade."

That was in 2015 - so if Stofan was right, the discovery of alien life could come very soon.

Yesterday saw the launch of the Peregrine 1 Moon lander. Although it soon ran into problems, it is only the first of a dozen missions scheduled for 2024 which could answer the biggest question of all. Are we alone in the universe?

Peregrine 1 will look at a strange area called the Gruithuisen Domes. They seem to be the result of volcanic activity. On Earth that could only take place with the aid of water.

Water is essential to life like ours. That makes it central to the search for aliens.

Scientists believe there is water to be found on two of Jupiter's moons. Nasa plans to launch a spacecraft to investigate one in October.

There could also once have been oceans on Mars, though not all scientists agree on this.

But finding water is not the same as finding alien life. With this in mind, Nasa has just started work on a new space telescopeA device which makes things look nearer than they are. . It will be called the Habitable Worlds Observatory (HWO).

So far scientists have found over 5,500 worlds orbiting other stars. The HWO's mission will be to look for life on 25 worlds similar to our own.

They will be within 100 light yearsA unit of measurement equal to the distance that light travels in one year, which is 9.4607 times 1012 km. That's nearly 6 million million miles! of Earth and roughly the same size. They will be neither too not nor too cold for water to exist.

The HWO will study their atmospheres for signs of life - for example, oxygen and methaneA particularly strong greenhouse gas produced by fossil fuels and cattle.. It will do this using ultravioletA form of electromagnetic radiation that cannot be seen by the human eye. and infraredA type of electromagnetic radiation (a wave with electricity). The wave is longer than light which humans can see and shorter than microwaves. light.

According to leading astronomerA scientist that studies the universe and space. Marc Postman: "This is the first telescope ever built that will be able to really address, in a scientific way, how common life is beyond the solar system."

Can we believe it this time?

Yes: There are all kinds of exciting developments in space exploration, including private enterprises like the Peregrine 1 mission. The HWO shows that Nasa is really committed to the search for aliens.

No: After decades of searching, we have still found no evidence of alien life. The HWO will probably not be ready for launch until 2040. The Europa probe is not scheduled to reach Jupiter until 2030.  

Or... Even if these missions establish that there is no other life on habitable worlds, they should not be considered a waste of time. They would prove that humans have a unique place in the universe.