Your Last-Minute Lunar Eclipse Toolkit: How And When To See, Stream And Photograph Friday’s Longest Partial Eclipse Since 1440 When is the lunar eclipse 2021? Here's everything you need to know about the upcoming partial lunar eclipse that will see 97% of the full Moon turn a weird reddish color, from how to photograph the "Blood Moon" to where and when the eclipse will be both visible and streamed live on YouTube.