Do aliens or other life forms exist in our universe? Space Scientist Maggie Aderin-Pocock might have the answer.
Every week, we answer a big question sent in from anywhere in the world, so ask us your questions in the comments and we'll try to get answers from BBC journalists and experts on the subject.
BBC My World is a brand new show for young people around the world, brought to you by executive producers Angelina Jolie and the BBC World Service. We've also partnered with Microsoft Education and BBC Learning to show you how the news is made, fact-check stories and spot fake news.