When Is Earth Day 2021?

This coming Thursday marks the 51st edition of Earth Day, the annual celebration of environmental protection.

While Earth Day falls on April 22, a three-day celebration including events, debates and discussions will kick off on Tuesday. A complete list of events planned for this year's celebration can be found on Earth Day's official website.

Here's all you need to know.

When is Earth Day 2021?

Earth Day falls on Thursday, April 22 this year.

What is Earth Day?

First held on April 22, 1970, Earth Day is an annual celebration supporting environmental protection with a different theme each year.

What is the theme of Earth Day 2021?

This year's theme is Restore Our Earth, with a particular focus on how to restore the world's ecosystems through natural processes, green technologies and innovative thinking.

"Climate change and other environmental degradations have broken our natural systems, leading to new and fatal diseases as well as a breakdown of the global economy," a statement on Earth Day's official website reads.

"But just as climate change and coronavirus painfully remind us of the harm we've caused, Restore Our Earth reminds us of the opportunities that lay ahead.

"We must Restore Our Earth not just because we care about the natural world, but because we live on it. Every one of us needs a healthy Earth to support our jobs, livelihoods, health and survival, and happiness. A healthy planet is not an option—it is a necessity."

Several events are planned around the world but, as was the case last year, most of them will take place virtually to comply with coronavirus restrictions.

On April 20, youth climate activists including Greta Thunberg, Alexandria Villaseñor, and Licypriya Kangujam will headline a global youth climate summit led by Earth Uprising. The event will kick off at 2:30 p.m. ET and will mark the start of three days worth of celebrations and debates, spanning several different countries.

The following day, Education International will lead the "Teach for the Planet: Global Education Summit", beginning at 7 a.m. ET.

On April 22, meanwhile, Earth Day Live will begin at 2 p.m. ET. The event will include and/or feature contributions from world climate leaders, grassroots activists, industry leaders, artists, musicians and influencers.

All events are available for live stream via Earth Day's official website.

Earth Day
Cypriot marine ecologist Louis Hadjioannou, 38, dives to photograph the coral, as he monitors the impact of climate change on the delicate fauna in the crystal clear waters of Glyko Nero in Ayia Napa, off the island's southeastern shore. - For the past nine years, Hadjioannou has systematically recorded the effect of rising sea temperatures of the corals near Cape Greko and is striving to raise awareness to save the marine diversity of the Cypriot waters for the next generation of islanders. Emily Irving-Swift/AFP/Getty Images