On October 28, 2021, the NASA/ESA Hubble Space Telescope shared a mesmerizing image of CW Leonis, a carbon star that looks like a glowing orange eye peering through a veil of cosmic dust. Situated about 300 light-years away in the constellation Leo, this star is a vivid reminder of the life cycles that govern our universe. The image captures the star's fiery hues and the thick clouds of soot surrounding it, presenting a hauntingly beautiful view just in time for Halloween.

When stars reach their twilight

CW Leonis is a type of red giant star known as a carbon star, characterized by its carbon-rich atmosphere. As stars evolve, they go through various stages, and in this phase, CW Leonis is shedding its outer layers, which creates the dense clouds of gas and dust we see in the image. This process is part of a star's natural life cycle, where, over millions of years, it exhausts its nuclear fuel and expands outward, eventually becoming a white dwarf surrounded by a nebula. Hubble's observation not only captures the beauty of this transition but also helps scientists understand more about stellar evolution.

What is a carbon star?

Carbon stars are a distinctive type of red giant that have a high abundance of carbon in their atmospheres. This carbon arises after the star has processed helium through nuclear fusion, leading to the formation of carbon compounds. Unlike typical stars that primarily fuse hydrogen into helium, carbon stars represent a late stage in stellar evolution, where the star's core has transformed and its outer layers are enriched with carbon. These stars are often surrounded by thick dust clouds, formed from the very materials they have expelled as they age.

Here are 3 fascinating insights about CW Leonis

1. CW Leonis is known to be one of the brightest carbon stars visible from Earth, making it a popular target for astronomers studying late-stage stellar evolution.

2. The dust surrounding CW Leonis is formed from carbon compounds that the star has shed, creating a rich, sooty environment that can obscure observations but also offers clues about the star's past.

3. As CW Leonis continues to shed its layers, it will eventually leave behind a white dwarf, and the expelled material will contribute to the interstellar medium, enriching future generations of stars and planets.

CW Leonis vs the Great Pyramid

To grasp the vastness of space, consider this: CW Leonis is about 300 light-years away from us. If you think of the Great Pyramid of Giza, which stands at about 481 feet tall, you can imagine needing to stack approximately 200,000 of these pyramids to reach the height of its atmosphere if it were to be scaled to our planet's dimensions. This comparison helps illustrate just how immense the distances in our universe truly are, emphasizing the incredible scale of stellar phenomena we observe.