In this episode of The Skyentists astronomers Kirsten Banks and Ángel López-Sánchez provide an overview of the many astronomical achievements obtained with the Spitzer Space Telescope (NASA), which mission is ending today, 30th January 2020. This small space telescope (its main mirror has a size of only 85 cm!) has observed the Universe in infrared light, providing astronomers astonishing views of star-forming regions, galaxies near and far, stars, exoplanets, diffuse cold gas and dust in the Milky Way, and much more. We have plenty of feedback for this episode, having a lot of fun with your mnemotechnic rules for "O B A F G K M", the standard stellar spectroscopic classification. For Space News Ángel brings again the famous red supergiant Betelgeuse, as it has continued dimming during the last couple of weeks. New research suggests that the current observed dimming (and also cooling, by 100 K) is consequence of the expansion of its huge atmosphere. It is expected that Betelgeuse reaches a minimum of brightness around late January - early February 2020, with an increasing of its brightness after that. Kirsten announces that she finished working at Sydney Observatory to focus on her PhD thesis at UNSW. She was in the public TV the other day (ABC's The Drum), where the name of "The Skyentists" was mentioned! For "What's Up" we invite everyone to look at the beautiful planet Venus (yes, in a dark place it casts shadows).