 Hello everyone, I'm Daniel from the Philippines and I'm here as a participant in the 64th London International Youth Science Forum and I'm doing a very special interview with the plenary speaker for today. So, can you please tell us a bit about yourself? So, I'm Hirania Pérez, I'm a cosmologist. I work as a professor of astrophysics in London and in Stockholm. Well, how did you end up becoming an astrophysicist? So, when I was a kid, I really, really loved everything about space. I loved science fiction and I wanted to be an astronaut. And when I was a bit older, I liked maths and physics in school. So, I realized I could combine the two and become an astrophysicist. What does a day in your work life look like, especially with an interesting job like astrophysicists? So, most of my day is involved in working with other people, my students, my collaborators, some of whom are scattered around the world. We work a lot in building big computer codes that can be applied to huge data sets to extract interesting astronomy. And I also teach. In three words, can you describe why you have the best job in the world? That's a hard one. Inspiration, discovery and teamwork. Honestly, if I could comment on it, you don't just have the best job in the world, but the best job in the universe. What are some stereotypes that people associate with astrophysicists that either aren't or are true? So, the one that really doesn't ring true anymore is that we are people who are just up in the middle of the night in deep dark places, working by ourselves, peering through a telescope. That's not really what astrophysics is like now. Much of our data comes from space or from remote observing facilities. And we do work in an office more than what's expected. But we get to travel to all sorts of cool places. What's been the highlight of your career so far? I think it was working on WMAP, which was an amazing data set that allowed us to piece together the history of the universe and its contents and its fate in a way that hadn't been possible before. That was incredibly exciting. So, what scientific breakthrough would you like to see in your lifetime? I would like to see the detection of dark matter. I think that's going to happen. And I would also like to see the detection of the first stars and very, very early sources in the history of the universe. This is your first time at LIYSF. How has it been? And what was your experience with talking to the students and answering their questions? It was incredible. It was just so inspiring to see so many students from all over the world with so much interest in learning Brilliant questions. I'm super impressed. I really loved it. A lot of people really do love astrophysics and astronomy. What advice do you have for young people wanting to pursue a future in astrophysics? Work on something that you love. And if it's astrophysics at the end of the day, that's great. But if it's something else, that's fine too. But working out what you want to do with your life and then doing that will bring you to fantastic places no matter what. Now, for all of you watchers, what's the crazy fact about space that the average person wouldn't know? Well, only 5% of the universe is made up of stuff like us. Everything else is dark matter and dark energy. And most people would be very alarmed to know that, but it's true. That's all the time we have for today. I would like to thank Professor Hiranya Peres for this very special interview. This is Daniel and you're watching LIYSF.