The Helium in Macy's Thanksgiving Day Parade Balloons Could Power Some Sweet Science - Gizmodo

The annual Macy’s Thanksgiving Day Parade in New York City uses roughly 400,000 cubic feet of helium gas in total to inflate its iconic giant balloons.

Though volume varies among the balloons—the Macy’s stars are 25 feet wide and tall, while the Dragon Ball Z Goku is 70 feet long and 56 feet tall—on average each balloon is apparently filled with about 12,000 cubic feet of helium, a widely cited figure.

(15,000 cubic feet is also widely cited. Macy’s did not respond to Gizmodo’s request for hard numbers.) A standard party balloon contains about 0.4 cubic feet of helium, so you’d need about 30,000 of them to approach the amount of helium used by a single Macy’s balloon.

Helium has different volumes in different states; 1 liter of liquid helium is equivalent to 26.63 cubic feet of the gas at one atmosphere of pressure, according to one industrial gas supplier.

In 2009, the agency signed a five-year contract to spend $56.5 million for 12.5 million liters of liquid helium and 212 million cubic feet of gaseous helium, according to SpaceNews.

Since Macy’s began using balloons for its parade, they’ve always contained helium except once, in 1958, when a helium shortage required the company to resort to air-filled balloons, lifted down the avenues with cranes.

Correction: A previous version of this article stated that helium is a superconductor; actually, it’s used to cool metals down to superconducting temperatures