Do you have weight in space? Is weightlessness an absence of gravity, or actually an absence of forces pushing against it? Andy unpicks what weight really is. Watch our experiments with water on a parabolic flight: https://www.youtube.com/watch?v=rzytpxtbCzQ Experience weightlessness in 360°: https://www.youtube.com/watch?v=mVJvyteAH0E On one hand, we learn at school that weight is the force on an object due to gravity; on the other, there’s a more subtle understanding of weight as something we feel and discuss every day. How these two ideas fit together can cause some confusion, particularly when the idea of weightlessness and astronauts in orbit on the ISS is introduced. When we tackled weightlessness for the 2016 CHRISTMAS LECTURES and our online series, A Place Called Space in December last year, we spent a long time thinking about weight. This video shares some of those thoughts. For example, when you’re in freefall, are you weightless? Is weightlessness a consequence of freefall, or is freefall, in fact, a consequence of weightlessness? Andy explains. You can watch our series all about space: https://www.youtube.com/watch?v=IcjYdEW_HLQ Subscribe for regular science videos: http://bit.ly/RiSubscRibe The Ri is on Twitter: http://twitter.com/ri_science and Facebook: http://www.facebook.com/royalinstitution and Tumblr: http://ri-science.tumblr.com/ Our editorial policy: http://www.rigb.org/home/editorial-policy Subscribe for the latest science videos: http://bit.ly/RiNewsletter