In less than a month, a mammoth alligator head will appear in Biscayne Bay. A laser beam will shoot from downtown to Miami Beach. And a stretch of sand will become a doomed lunar landscape.

Don’t call the authorities. It’s all art.

The worldwide draw known as Art Basel Miami Beach — plus more than 20 satellite fairs, a brand new music and art festival and untold numbers of private exhibits, events, parties and large-scale installations — arrive for a packed week in early December.

In its 11th year, the main event, which runs from Dec. 6-9, will continue to expand beyond the Miami Beach Convention Center. Art Basel director Marc Spiegler said the outdoor activities known as “Art Public” in Collins Park will include more projects and performances.

“One of the things we really wanted to do was recapture the outdoor aspect,” he said. In addition to the happenings in the park, the fair will show a film from sundown on Dec. 8 through sunrise the next day on the outside wall of the New World Center.

Another outdoor project — with details still sketchy — comes from artist duo Kolkoz, which will recreate the landing area of the Apollo 11 mission that first brought man to the moon. The site will then, according to Spiegler, be destroyed by beach soccer games.

“These are the exciting things we think are going to extend the show beyond the halls,” he said.

The activities timed to coincide with Art Basel will extend even farther beyond the halls.

Brand new, the two-day UR1 Music & Art Festival will move into Bayfront Park Dec. 8 and 9 with performances from a range of musical genres (think Kanye West, Jane’s Addiction and Keane) and an art section featuring 40 installations and exhibits — including from 20 local artists.

“I think Miami’s kind of unique where it’s really prepared to offer an acculturated version of such a festival with a strong legitimate art component,” said David Glass, the festival’s art production director.

UR1 co-founder Alex Omes, who is also a co-founder of Ultra Music Festival, said he is not concerned that all the other events in town at the same time will detract from the festival.

“When things like this happen, that’s when the big shows are most successful,” he said.

Tickets for two-day admission cost $99 or $149, depending on what time you want to arrive, and are required to see the art and music at the festival. But one installation will be free and unavoidable to anyone in the surrounding area.

In a collaboration, KIWI Arts Group, LaserNet and Andy Warhol contemporary Ultra Violet will send a continuous laser beam from Bayfront Park to Miami Beach every night Dec. 5-9.

“If you’re in downtown, going over the causeway bridge, in certain areas of South Beach, you’ll be able to see that laser,” Glass said.

Also visible at various points around Biscayne Bay: a 90-foot long, 30-foot wide alligator head made of steel and floating on a barge. Floating Tile Art: Gator in the Bay is scheduled to appear in Miami waters by Dec. 5.

“It’s going to look like this magical gator literally just popping its head up out of the water,” said project coordinator Cesar A. Becerra, a Miami native and South Florida historian.

Lead artist Lloyd Goradesky is at work on the project now in West Broward. The steel structure will be covered in fabric and resin and crafted to look like real skin.