NASA’s Hubble Examines Cloud-9, First of New Type of Object

Unveiling the Mysteries of Cloud-9: A Starless, Gas-Rich, Dark-Matter Cloud

The universe has long been shrouded in mystery, with many of its secrets waiting to be unraveled. Recently, a team of astronomers using NASA's Hubble Space Telescope has made a groundbreaking discovery that sheds light on the early universe and the nature of dark matter. Meet Cloud-9, a starless, gas-rich, dark-matter cloud that has left scientists in awe.

A Window into the Dark Universe

Cloud-9 is a Reionization-Limited H I Cloud (RELHIC), a type of object that has been theorized to exist but never directly observed until now. This cloud is a relic from the early universe, a fossil leftover that has not formed stars. The discovery of Cloud-9 provides a unique window into the intrinsic properties of dark matter clouds, which are difficult to study through traditional observations.

The Discovery of Cloud-9

Cloud-9 was discovered three years ago as part of a radio survey by the Five-hundred-meter Aperture Spherical Telescope (FAST) in Guizhou, China. The finding was later confirmed by the Green Bank Telescope and the Very Large Array facilities in the United States. However, it wasn't until the team turned Hubble toward the cloud that they could definitively determine that the failed galaxy contains no stars.

A Starless Galaxy

Cloud-9 is a small, compact, and highly spherical object, measuring about 4,900 light-years in diameter. The core of this object is composed of neutral hydrogen, with a mass of approximately one million times the mass of the Sun. Assuming that the gas pressure is balancing the dark matter cloud's gravity, which appears to be the case, researchers calculated Cloud-9's dark matter must be about five billion solar masses.

The Significance of Cloud-9

The discovery of Cloud-9 has significant implications for our understanding of the early universe and the nature of dark matter. Dark matter is a type of matter that does not emit, absorb, or reflect any electromagnetic radiation, making it invisible to our telescopes. However, its presence can be inferred through its gravitational effects on visible matter. Cloud-9 provides a unique opportunity to study the properties of dark matter in a starless galaxy.

The Future of Cloud-9

Cloud-9 may eventually form a galaxy in the future, provided it grows more massive. However, how that would occur is under speculation. If it were much bigger, say, more than 5 billion times the mass of our Sun, it would have collapsed, formed stars, and become a galaxy that would be no different than any other galaxy we see. If it were much smaller than that, the gas could have been dispersed and ionized and there wouldn't be much left.

The Hubble Space Telescope

The Hubble Space Telescope has been operating for more than three decades and continues to make groundbreaking discoveries that shape our fundamental understanding of the universe. Hubble is a project of international cooperation between NASA and the European Space Agency (ESA). NASA's Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope and mission operations. Lockheed Martin Space, based in Denver, also supports mission operations at Goddard. The Space Telescope Science Institute in Baltimore, which is operated by the Association of Universities for Research in Astronomy, conducts Hubble science operations for NASA.

Conclusion

The discovery of Cloud-9 is a significant milestone in our understanding of the universe. This starless, gas-rich, dark-matter cloud provides a unique window into the intrinsic properties of dark matter clouds. The implications of this discovery are far-reaching, and it has the potential to revolutionize our understanding of the early universe and the nature of dark matter. As we continue to explore the universe with the Hubble Space Telescope, we may uncover even more secrets and mysteries that will continue to shape our understanding of the cosmos.

Related Images & Videos

Cloud 9, Starless Gas Cloud: Magenta is radio data from the ground-based Very Large Array (VLA) showing the presence of Cloud-9. The dashed circle marks the area where researchers focused their search for stars. Hubble found no stars within Cloud-9. The few objects within its boundaries are background galaxies.
Cloud 9, Starless Gas Cloud Compass Image: This is an annotated composite image of Cloud-9, a Reionization-Limited H I Cloud (RELHIC), as captured by the Hubble Space Telescope's ACS (Advanced Camera for Surveys) and the ground-based Very Large Array (VLA) radio telescope.
Cloud 9, Starless Gas Cloud Video: This annotated video shows the location of Cloud-9 on the sky. As the video zooms into this gas-rich, dark-matter cloud, it becomes evident that there are no stars within it. Only background galaxies appear behind Cloud-9, which has survived since the universe's early days.

Details
- Last Updated: Jan 05, 2026
- Editor: Andrea Gianopoulos
- Location: NASA Goddard Space Flight Center
- Contact: Media
  - Claire Andreoli
  - Ann Jenkins, Christine Pulliam
Related Terms
- Hubble Space Telescope
- Astrophysics
- Astrophysics Division
- Dark Matter
- Galaxies
- Goddard Space Flight Center
Related Links and Documents
- Science Paper: "The First RELHIC? Cloud-9 is a Starless Gas Cloud" by G. Anand et al., PDF (15.34 MB)
- Release on ESA/Hubble website
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