Zhúlóng is an extremely massive
grand-design spiral galaxy located at a redshift distance of z=5.2 (12.8 Gly) in the
constellation
A constellation is an area on the celestial sphere in which a group of visible stars forms Asterism (astronomy), a perceived pattern or outline, typically representing an animal, mythological subject, or inanimate object.
The first constellati ...
of
Sextans
Sextans is a faint, minor constellation on the celestial equator which was introduced in 1687 by Polish astronomer Johannes Hevelius. Its name is Latin for the astronomical sextant, an instrument that Hevelius made frequent use of in his obs ...
. It is believed to be the most distant known grand design spiral galaxy. Spiral galaxies beyond red shift 3.0 are generally rare with only a few known.
The galaxy has well-defined
spiral arms
Spiral arms are a defining feature of spiral galaxies. They manifest as spiral-shaped regions of enhanced brightness within the galactic disc. Typically, spiral galaxies exhibit two or more spiral arms. The collective configuration of these arms ...
that have dense
star formation
Star formation is the process by which dense regions within molecular clouds in interstellar space—sometimes referred to as "stellar nurseries" or "star-forming regions"—Jeans instability, collapse and form stars. As a branch of astronomy, sta ...
regions while the core is quiescent. However the rate of star formation is low forming 66 solar masses of stars per year. The size of this galaxy is comparable to the
Milky Way galaxy
The Milky Way or Milky Way Galaxy is the galaxy that includes the Solar System, with the name describing the galaxy's appearance from Earth: a hazy band of light seen in the night sky formed from stars in other arms of the galaxy, which are ...
, being an estimated 62,000 light years in diameter.
It has a mass of around 100 billion solar masses.
Naming
The galaxy was named Zhúlóng meaning “Torch Dragon” in
Chinese mythology
Chinese mythology () is mythology that has been passed down in oral form or recorded in literature throughout the area now known as Greater China. Chinese mythology encompasses a diverse array of myths derived from regional and cultural tradit ...
. In the myth,
Zhúlóng is a powerful red solar dragon that creates day and night by opening and closing its eyes, symbolizing light and cosmic time.
Discovery
Zhúlóng was discovered by a team led by
Mengyuan Xiao, and announced in a paper submitted to
Astronomy & Astrophysics
''Astronomy & Astrophysics (A&A)'' is a monthly peer-reviewed scientific journal covering theoretical, observational, and instrumental astronomy and astrophysics. It is operated by an editorial team under the supervision of a board of directors re ...
on 17 December 2024, and published on 16 April 2025.
The discovery was surprising to astronomers, who had previously believed that spiral galaxies took billions of years to develop.
Image gallery
File:Zhúlóng - The most distant spiral galaxy (full).jpg, PANORAMIC Survey showing position of Zhúlóng, imaged by the James Webb Space Telescope
The James Webb Space Telescope (JWST) is a space telescope designed to conduct infrared astronomy. As the largest telescope in space, it is equipped with high-resolution and high-sensitivity instruments, allowing it to view objects too old, Lis ...
References
External links
{{Sextans
Sextans
Spiral galaxies
Astronomical objects discovered in 2024