Watch the Annual ‘Whale Wash’ at the American Museum of Natural History

Measuring 100 feet in length and weighing up to 400,000 pounds, the blue whale is the largest animal ever known to have existed.

To help people appreciate the truly gargantuan dimensions of this elusive oceangoer, the American Museum of Natural History (AMNH) unveiled an arching scale model of a blue whale in 1969. Suspended above the Milstein Hall of Ocean Life, the foam-and-fiberglass replica has become one of the most widely recognized museum displays in the world.

And on Wednesday morning, you can watch this iconic NYC resident get some much-needed TLC.

The AMNH whale's 94-foot-long, 21,000-pound frame has a huge surface area, just like the animal it emulates, which means it accumulates quite a lot of dust as the months roll by. To prevent it from getting too grody, a special cleaning crew assembles once a year to give the old girl a good wipedown with extendable vacuums and brushes.

A livestream of this annual "Whale Wash" will run from 11 AM to noon EST on September 7 at the below link. Museumgoers can check it out in person, as the Milstein Hall will remain open.

Livestream link to the Whale Wash. Video: American Museum of Natural History/YouTube

These yearly cleanings are not the only cosmetic upgrades that the AMNH blue whale has undergone since it was first put on display, 47 years ago. The model also received a major makeover in 2003, to make it more scientifically accurate. This was necessary partly because, when the replica was first being prepared and mounted in the late 1960s, wild blue whale sightings were incredibly rare: industrial whaling had killed hundreds of thousands of individual animals, seriously depleting the global population.

"Even though men had walked on the Moon, little was known about what blue whales looked like in their natural habitat," says ichthyologist Melanie Stiassny, the lead curator for the 2003 renovation, in an AMNH article.

Because curators had never seen wild whales, they based the AMNH model on the body of a dead female blue whale found in 1925. Accordingly, the eyes were painted to be large and bulbous and its skin was grey instead of blue, but that was only because it was "modeled on a corpse," Stiassny said.

The new incarnation has less googly eyes, befitting of a normal alive whale, along with a belly button to reflect the mammalian heritage it shares with humans. Its fins and fluke were adjusted, and its macabre grey coloring was painted over with 25 gallons of cobalt and cerulean blue.

Now you can watch on as museum staff makes this relatively fresh coat of paint shimmer and shine again for yet another year, to dazzle new visitors and serve as a constant reminder to protect the spectacular creature it represents.

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