Going, Going, Gone?

Look up at the sky—it’s a bird! It’s a plane! It’s Snoopy, Pikachu, and Sonic the Hedgehog! Seeing these characters floating overhead can mean just one thing—it’s the Macy’s Thanksgiving Day Parade! The annual New York City event rings in the holiday season with floats, performers, and giant balloons.

To pull off the parade, it takes hundreds of people, plus one special substance: helium. Helium gas is less dense, or has less matter in a given space, than air. That’s what allows it to lift up balloons. Helium also has important uses in medicine, technology, and more (see Beyond Balloons).

But helium is a nonrenewable resource. That means there is a limited amount of it on Earth. Helium is found in cracks in rocks underground. Mining it is difficult and expensive. At times in recent years, there hasn’t been enough helium available to meet the world’s demand. That has some people worried: Is the world running out of this very special gas?

Look up at the sky. It’s a bird! It’s a plane! It’s Snoopy, Pikachu, and Sonic the Hedgehog! These characters are floating overhead. That can mean just one thing. It’s the Macy’s Thanksgiving Day Parade! The event takes place in New York City each year. It rings in the holiday season with floats, performers, and giant balloons.

It takes hundreds of people to pull off the parade. It also takes one special substance—helium. Helium gas is less dense than air. That means it has less matter in a given space. That’s what allows it to lift balloons. Helium also has important uses in medicine, technology, and more (see Beyond Balloons).

But there’s a limited amount of helium on Earth. Helium is found in cracks in rocks underground. Mining it is difficult and costly. There hasn’t been enough helium at times in recent years. Suppliers couldn’t meet the world’s demand. That has some people worried. Is the world running out of this very special gas?

Helium is one of 118 known elements in the universe. Elements are the building blocks of everything from germs to giant stars. Each element has different properties. Some are magnetic, while others glow. Helium is the second-lightest element. That’s why people use it to fill blimps and balloons (see Lighter Than Air). Helium’s other properties make it useful too. It has a very low condensation point. That’s the temperature at which it turns from gas to liquid. The temperature, -269°C (-452°F), can be reached on Earth only by using special machines.

Because liquid helium is so cold, it is often used to keep machines from overheating. For example, the MRI machines that doctors sometimes use to look at the insides of a person’s body can produce a lot of heat. Sending cold liquid helium through these machines keeps them from getting too hot and shutting down.

Helium is also useful because it doesn’t easily react with other elements. Chemical reactions cause substances with new properties to form. The stability of helium “makes it safe to use for all kinds of purposes,” says Maosheng Miao. He’s a physicist from California State University, Northridge.

Helium is one of 118 known elements in the universe. Elements are the building blocks of everything from germs to giant stars. Each element has different properties. Some are magnetic. Others glow.

Helium is the second-lightest element. That’s why people use it to fill blimps and balloons (see Lighter Than Air). Helium’s other properties also make it useful. It has a very low condensation point. That’s the temperature at which it turns from gas to liquid. The super-cold temperature, -269°C (-452°F), can be reached only by using special machines.  

Helium stays in liquid form when cooled. It’s often used to keep machines from overheating. Doctors use MRI machines to look at the insides of a person’s body. These machines produce a lot of heat. Liquid helium is sent through the devices. This keeps them from getting too hot and shutting down.

Helium also doesn’t easily react with other elements. Chemical reactions cause substances with new properties to form. Helium is very stable. That “makes it safe to use for all kinds of purposes,” says Maosheng Miao. He’s a physicist at California State University, Northridge. 

The U.S. produces more helium than any other country in the world (see Top Helium Sources). The gas used in the Macy’s parade is mined in Kansas. How does it get to New York City streets?

To mine helium, a machine drills into the ground until it hits a pocket of gas. The gas is collected into a machine that cools it down. That cold temperature causes the helium to change forms, transforming into a liquid. This allows it to be separated from other gases that may have been collected.

Liquid helium is transported in containers. It’s turned back into a gas before it gets to New York City. Staff fill the giant balloons the day before the parade. “At first, the balloons look like flattened pancakes,” says Matt Kaprielian, assistant balloon manager at Macy’s Parade Studio. “As the balloons fill up, they take shape and begin to float.”

After the parade, the balloons are packed away to “hibernate” until next year, says Kaprielian. The helium is released into the air. The superlight gas floats up and into the atmosphere.

The U.S. produces more helium than any other country in the world (see Top Helium Sources). The gas used in the Macy’s parade is mined in Kansas. How does it get to New York City streets? 

A machine drills into the ground to mine helium. It digs down until it hits a pocket of gas. The gas is collected into a machine that cools the gas. That cold temperature causes the helium to change forms. It turns from a gas to a liquid. This allows it to be separated from other gases that may have been collected. 

Liquid helium is shipped in containers. It’s turned back into a gas before it gets to New York City. Staff fill the giant balloons the day before the parade. “At first, the balloons look like flattened pancakes,” says Matt Kaprielian. He works as the assistant balloon manager at Macy’s Parade Studio. “As the balloons fill up, they take shape and begin to float.” 

The balloons are packed away after the parade. They “hibernate” until next year, says Kaprielian. The helium is released into the air. The superlight gas floats up into the atmosphere.  

But is all that helium too precious to release? In recent years, the element has sometimes been hard for industries to get. Because helium is so expensive to mine, companies often charge high prices for it. Wars and other conflicts can cut off supply and cause the price to increase. Some scientists have had to shut down machines because they don’t have helium to keep them running.

Luckily, there is still plenty of helium on Earth, says Allison Sandoval. She works for the U.S. Bureau of Land Management, which manages the U.S. helium supply. “There are about 80 years of known helium reserves underground in Wyoming alone,” she says.

As companies mine the known helium sources, they are also searching for more of the gas in the ground. Industries that rely on the element are also finding ways to conserve it. Scientists are collecting helium after it’s used in experiments. Macy’s parade organizers are looking for ways to recycle the helium they use for balloons.

With these efforts, experts believe helium will be around to fill parade balloons for decades to come. “People worry about important natural resources running out,” says Sandoval. “Fortunately, helium is not one of those things.”

But is all that helium too precious to release? The element has sometimes been hard for industries to get in recent years. Helium is expensive to mine. So companies often charge high prices for it. Wars and other conflicts can cut off supply. That can cause the price to rise. Some scientists have had to shut down their machines. They don’t have helium to keep them running. 

Luckily, there is still plenty of helium on Earth, says Allison Sandoval. She works for the U.S. Bureau of Land Management. It manages the U.S. helium supply. “There are about 80 years of known helium reserves underground in Wyoming alone,” she says. 

Companies continue to mine known helium sources. And they are also searching for more of the gas in the ground. Many industries that rely on the element are finding ways to conserve it. Scientists reuse helium after experiments. Macy’s parade organizers are looking for ways to recycle the helium they use for balloons.

Experts believe these efforts will help. Helium will be around to fill parade balloons for decades to come. “People worry about important natural resources running out,” says Sandoval. “Fortunately, helium is not one of those things.”