A cosmic lion in space

NGC 2392 gets its nickname from its striking appearance. In images, the nebula resembles the face of a lion, surrounded by a hazy structure that looks like a mane.

Hubble photographed the nebula in visible light in 2000. Webb’s infrared observations now provide another perspective, allowing astronomers to see features that are difficult to detect in visible wavelengths.

Webb’s powerful infrared vision reveals compact clumps of dust, ionised gas and intricate shells surrounding the central star. These structures are the result of thousands of years of material being expelled from the dying star.

The death of a star created the Lion Nebula

Despite its dramatic appearance, the Lion Nebula is not the result of a massive supernova explosion.

Instead, NGC 2392 was created by a lower-mass star similar to the Sun.

As the star reached the final stages of its life, it could no longer maintain the nuclear reactions that had powered it for most of its existence. The star became unstable and began shedding its outer layers into space.

Those layers of gas and dust formed the expanding planetary nebula we see today.

At the centre of the nebula, the star’s extremely hot core remains behind as a white dwarf. Its intense radiation continues to energise the surrounding material and shape the nebula.

Webb reveals the nebula’s hidden structures

One of the most fascinating features visible in Webb’s images is the bright bubble of ionised gas surrounding the central white dwarf.

This expanding bubble forms much of the lion’s apparent “face.” As it moves outward, it interacts with and destroys dust in its path.

The nebula also contains a complex system of rings and shells. Astronomers are still working to understand exactly how these intricate structures formed and evolved.

The apparent “mane” surrounding the lion’s face is actually the interior of a dust shell illuminated by the central white dwarf.

Within this region are compact clumps of dust that have survived the star’s intense radiation. Some of these structures appear to have long, comet-like tails, creating the remarkable texture seen in Webb’s observations.

A planetary nebula won’t last forever

Although the Lion Nebula looks frozen in time in Webb’s images, it is actually changing continuously.

Gas and dust are moving away from the central white dwarf, causing the nebula to expand and evolve.

Astronomers estimate that NGC 2392 will eventually disperse into space in roughly 10,000 years.

That may sound like an extremely long time, but on astronomical timescales it is remarkably short.

The nebula therefore represents a temporary stage in the long life cycle of a star.

What Webb is teaching us

The Lion Nebula provides astronomers with an opportunity to study what happens when stars similar in mass to our Sun reach the end of their lives.

By observing the different layers of gas and dust at infrared wavelengths, Webb can help scientists understand how dying stars release material into space and how those materials become part of the interstellar environment.

These processes are also important to the broader story of the Universe. Stars at this stage contribute significant amounts of dust and other material back into space, helping enrich the environment from which future generations of stars and planetary systems can form.

A beautiful snapshot of stellar evolution

The new Webb observations of NGC 2392 show that the death of a star can create structures of extraordinary complexity and beauty.

What looks like a glowing lion floating in space is actually the expanding remains of a dying star, illuminated by the hot white dwarf at its centre.

Webb has effectively given astronomers a highly detailed snapshot of this transformation — capturing the Lion Nebula during one brief chapter in its evolution.

And like many of Webb’s observations, the image is more than just beautiful: it provides scientists with another opportunity to understand how stars live, die and return material to the cosmos.

The Lion Nebula is still changing, and in thousands of years, its beautiful structure will gradually fade away into interstellar space.

Image credit: NASA, ESA, CSA, STScI. Image processing: A. Pagan (STScI).