Helium Discovery Day

Written by: Lisa Chang - (updated: August 17th, 2025 at 9:10AM)

Helium, the second-most abundant element in the universe, carries a captivating history that stretches back to the 18th century. While today it finds widespread use in everything from festive balloons to advanced medical imaging, the discovery of helium is credited to the pioneering efforts of French astronomer Pierre Janssen and British chemist Norman Lockyer. They first detected it on August 18, 1868, during a total solar eclipse in India—an event that has since been commemorated as Helium Discovery Day.

This remarkable discovery not only revolutionized scientific research but also paved the way for diverse industrial and medical applications. Let's delve deeper into the fascinating journey that led to this groundbreaking find.

Unraveling the Mystery of the Yellow Line

In the mid-19th century, scientists were still unraveling the complexities of sunlight. During a solar eclipse, the sun's corona, typically hidden by the sun’s brilliance, becomes visible, revealing its spectral lines. On that pivotal day in August 1868, Janssen and Lockyer, observing the eclipse from the city of Guntur in India, noticed an enigmatic yellow line in the solar spectrum—a phenomenon never before witnessed.

Intrigued by this spectral anomaly, they embarked on a quest to identify its source. After extensive research, they concluded that the yellow line was produced by an unknown element, which they named "helium," inspired by the Greek word "helios," meaning sun.

What Does Helium Mean for Our Daily Lives?

Helium, the gas that playfully lifts our balloons and humorously alters our voices, has evolved to become an indispensable component across various industries:

• Medical Imaging: Helium plays a critical role as a coolant in superconducting magnets, which are fundamental to the operation of Magnetic Resonance Imaging (MRI) machines, enabling non-invasive diagnostic imaging.
• Balloons and Celebrations: Its most delightful use is in inflating balloons, adding joy and buoyancy to our celebrations and events.
• Welding and Cutting: Helium serves as a shielding gas in welding and cutting processes, ensuring precision and high-quality finishes.
• Scientific Research: Helium is used in cryogenics, helping scientists reach ultra-low temperatures necessary for advanced research.

Celebrating Helium Discovery Day

As we commemorate the anniversary of Pierre Janssen and Norman Lockyer's groundbreaking discovery, we reflect on the myriad ways helium has enriched our lives. From advancing medical research and supporting industrial processes to simply adding a whimsical touch to our festivities, helium remains an integral part of our everyday world.

Let's take a moment to raise a (helium-filled) balloon in honor of the trailblazers who opened the door to this extraordinary discovery. Their legacy continues to inspire and fuel the curiosity of future generations of scientists and innovators.

Happy Helium Discovery Day!