Scientists from the University of Cambridge have made an exciting discovery that might be the first strong hint of life outside our solar system. Led by Professor Nikku Madhusudhan, the research team found special chemicals in the atmosphere of a far-away planet that could be signs of living things.
The team discovered two chemicals called dimethyl sulfide (DMS) and dimethyl disulfide (DMDS) on a planet outside our solar system. On Earth, these chemicals are mostly made by tiny living things in the ocean. Finding them on another planet is very exciting because it might mean there are living things there too.
This discovery happened on a planet called K2-18b, which is 124 light-years away from Earth (about 117.37 lakh crore kilometers). That’s very, very far – so far that it would take 124 years traveling at the speed of light to reach it! This planet is in a star group called Leo, which looks like a lion in the night sky.
The scientists used a very powerful space telescope called the James Webb Space Telescope to make this discovery. This telescope can see things very far away. It works by looking at the light that passes through the planet’s atmosphere when the planet moves in front of its star. Different chemicals in the atmosphere change the light in different ways, creating what scientists call a “chemical fingerprint.”
What are DMS and DMDS, and why do they matter?
- DMS is mostly made by tiny plants in Earth’s oceans
- DMDS is made by bacteria and plants on Earth
- Scientists call these “biosignatures” – chemicals that usually come from living things
- No known non-living processes on Earth make these chemicals in large amounts
- Finding them on another planet might mean there are living things there
What’s really interesting is how much of these chemicals the scientists found. The levels of DMS and DMDS on K2-18b are thousands of times higher than what we find on Earth! Here’s how they compare:
| Planet | DMS/DMDS Levels |
|---|---|
| K2-18b | More than 10 parts per million |
| Earth | Less than 1 part per billion |
| Other planets in our solar system | None detected |
K2-18b is what scientists call a “Hycean world” – a special type of planet that might be good for life:
- It has huge oceans of liquid water covering its surface
- It has a thick atmosphere rich in hydrogen
- It’s bigger than Earth (up to 2.6 times Earth’s size)
- It sits in the “habitable zone” where water can exist as a liquid
- It could possibly support simple life forms like microbes
The scientists are being careful about their claims. Their findings have what they call “three-sigma statistical significance,” which means they’re pretty confident but not 100% sure. Co-authors Måns Holmberg from the Space Telescope Science Institute and Savvas Constantinou helped with this research. They all agree that more studies are needed to confirm if these chemicals really come from living things.
This discovery is very important for our search for life beyond Earth. It opens up new possibilities for finding and studying places where life might exist. If confirmed, it would be the first evidence of life outside our solar system – a truly amazing breakthrough that would change how we think about our place in the universe.
