How long is a day? On this explainer, Neil deGrasse Tyson and comic co-host Chuck Nice explore skyscrapers and how the sun sets later at the top. Could you potentially see two sunsets in one day? How fast does the sun set? Learn about sunsets on The Empire State Building, The Burj Kalifa, and The World Trade Center. Neil reads us his piece on 9/11 called “Sunset on the World Trade Center.” We explore different definitions of a day and when it starts and ends. What is a day in the arctic? Get the NEW Cosmic Queries book (5/5 ⭐s on Amazon!): https://amzn.to/3dYIEQF Support us on Patreon: https://www.patreon.com/startalkradio FOLLOW or SUBSCRIBE to StarTalk: Twitter: http://twitter.com/startalkradio Facebook: https://www.facebook.com/StarTalk Instagram: https://www.instagram.com/startalk About StarTalk: Science meets pop culture on StarTalk! Astrophysicist & Hayden Planetarium director Neil deGrasse Tyson, his comic co-hosts, guest celebrities & scientists discuss astronomy, physics, and everything else about life in the universe. Keep Looking Up! #StarTalk #neildegrassetyson 0:00 - Introduction 0:56 - Crow’s Nest 1:57 - Earth’s Shape 2:48 - Sunset On Top Of A High-Rise 4:06 - Burj Khalifa 4:33 - Religious Traditions at Sundown 8:37 - How Much Later The Sun Sets 9:15 - Sunset On The World Trade Center 11:47 - Closing Notes