International Observe the Moon Night is an annual worldwide public event that encourages observation, appreciation, and understanding of our Moon and its connection to NASA planetary science and exploration. On October 16, 2021, everyone on Earth is invited to join the celebration through hosting or attending a public or private event and/or by registering as an individual observer. Participation in International Observe the Moon Night has steadily grown over the past 11 years. The estimated participation in 2020 was 500,000 individuals worldwide. Events and observers participated on seven continents in 104 countries, all 50 US States, Puerto Rico, Guam, Washington DC, and the US Virgin Islands. In 2020, over one third of registered events were held virtually. In 2020 the International Observe the Moon Night team hosted its first ever live stream produced simultaneously for YouTube Live, Twitch, and NASA TV’s channel. We invite the scientific community to join and support the celebration this year by hosting events, serving as guest speakers for events, participating in the 2021 live stream, and by participating as an individual observer. Learn more and register an event https://moon.nasa.gov/observe-the-moon-night/.