After the Pentagon revealed hundreds of reports on unidentified aerial phenomena.
We know that for every five stars, there is one star that has a planet similar to Earth. Lisa Kaltenegger, an astrophysicist at Cornell University (USA), explains that there are 200 billion stars just in our Milky Way galaxy. Therefore, there could be up to 40 billion potential planets that resemble the world we live in.
NASA’s James Webb Space Telescope.
I am a member of the Near Infrared Camera and Slitless Spectrograph (NIRISS) team, one of the instruments on the James Webb Space Telescope. Currently, we are observing the Trappist-1 system along with the rocky worlds within this habitable zone. Therefore, some of these worlds may harbor life.
At present, we are focusing on gases (the things we inhale and exhale). If you see something unusual on one of these planets – such as a smear on the ground – it could be a sign of life. Therefore, we use the telescope to search for signs of life. You have to be very careful when examining signs of life, because it’s entirely possible that a type of geology unlike anything on our planet may exist, and you may not even be aware of it.
Life on Earth requires water, but just having water is not enough… We hope to find oxygen, but just oxygen alone is not sufficient either. We also want to discover methane. This is why I initially created models of Earth through various geological stages to determine the timeframe in which signs of life here could be observed. No one has ever attempted to do this. How long can you see Earth as a habitable place? We estimate around 2 billion years, as that is the time span during which the combination of oxygen and methane impacts the atmosphere of this planet.
So, we are preparing to have the capability to detect life in the universe because for the first time, we know that many planets exist, and we know where the closest planets are. We also understand that on a planet like Earth, over a span of 2 billion years, you need to observe both the air and the atmosphere.
With the James Webb Telescope, a space observatory designed to detect infrared radiation from objects in the solar system, we can only observe the atmosphere of a planet when it passes between us and its star. The light from the star will then be filtered through that planet’s atmosphere.
That light reaches my telescope after being filtered through the planet’s atmosphere. The molecules that the light interacts with have different structures; they require different energies – different colors of light to vibrate and rotate. Thus, by observing which colors are missing, I can tell you what is in that planet’s atmosphere. I cannot see the surface of the planet because if the light hits the surface, it will reflect back and not pass directly through my telescope. Therefore, for now, we are limited to searching for types of gases.
The next generation of telescopes we are designing – called the Habitability Observatory – will be larger than James Webb, with missions planned around 2035/2040. After that, we want to learn more about the planets, about their surfaces, about the colors we can see, and then compile evidence.
Two exoplanets of Trappist-1 passing in front of their star (Illustration).
When you look at Earth’s evolutionary process, the more oxygen we have, the more abundant life becomes. Therefore, if we find a planet with 30% oxygen, similar to the time of the dinosaurs, large or complex organisms could exist. This would be an incredible discovery, and I believe humanity will regard this as its greatest adventure. The scientific community is spread across the globe, and scientists are closely connected – countries will pool resources to build a truly large telescope.
If another civilization finds us, hypothetically, they could be a hundred light-years away. And the question is: Why haven’t they come here? Well, I don’t know if we are that appealing. I love Earth, but it is amusing to assume that everyone would want to immediately visit and talk to us.
I believe that by attempting to search for life or other Earth-like planets, everything we learn out there will help us understand our own planet and protect it better. I think we will discover a habitable planet in the near future; that is why I am working very hard to make this a reality. And many others are as well.
Everyone hopes that what we find in the Trappist-1 system could mean something significant, that this is indeed the first sign of an intriguing biochemical process that might indicate life. We are all excited because for the first time in history, we have the tools and capabilities to explore that.
