Phosphine is a gas that is made up of atoms of phosphorus and hydrogen. It is kind of like the air we breathe but it has different stuff in it. People sometimes use it to make things like pesticides and other useful chemicals.
Phosphine is also known for being really stinky and has a smell kind of like rotten fish or garlic. Even though it smells really bad, scientists study it because it is important to understand how it works in the world around us.
Sometimes, phosphine can be found naturally in places like swamps and sewers. But scientists have also found evidence of phosphine on other planets like Venus, which is really far away from Earth. This is really interesting because it gives scientists clues about how other planets may work and if there could be life outside of Earth.
In order to learn more about phosphine, scientists use special tools to study it. Sometimes they use big machines that can detect tiny amounts of the gas in the air. Other times they might use microscopes to look at the atoms that make up the gas.
Overall, phosphine might not seem like a big deal to us, but it plays a very important role in chemistry and helps us understand the world around us.