This is a truly special confluence of spookiness; a Halloween full moon visible for most time zones on Earth hasn’t happened since 1944, according to the Farmers’ Almanac. It won’t happen again until 2039.

But wait, there’s more: The Oct. 31 full moon also happens to be a “blue moon,” a designation for the second full moon to occur in a single calendar month. Blue moons are relatively rare as well, occurring on average just once every 2.5 years or so. We last saw one in March 2018. The next one is in August 2023.

You can watch the Halloween Blue Moon live online in a webcast from the Virtual Telescope today starting at 12:30 p.m. EDT (1630 GMT). Astrophysicist Gianluca Masi will webcast live views of the full moon as it rises over Rome, Italy. You can follow the webcast on  Virtual Telescope website here, and on YouTube. It will also be carried live on this page at start time.