Astronomy Cast Ep. 691: Jupiter’s Changing Red Spot by Fraser Cain & Dr. Pamela Gay Streamed live on Sep 25, 2023. Jupiter’s Great Red Spot is one of its most iconic features. First seen hundreds of years ago. Although it’s certainly long lasting, it’s been changing in size over the last few decades. Shrinking, changing in color. Is it fading away? And what can the changes tell us about storms on giant planets?