astrobiologist

Could invisible aliens really exist among us? An astrobiologist explains: They probably won't look anything like this. Martina Badini/Shutterstock Life is pretty easy to recognise. It moves, it grows, it eats, it excretes, it reproduces. Simple. In biology, researchers often use the acronym “MRSGREN” to describe it. It stands for movement, respiration, sensitivity, growth, reproduction, …