Nav: Home

Thousands of new globular clusters have formed over the last billion years

November 04, 2019

Globular clusters may contain hundreds of thousands of stars and may even have as many as ten million stars that essentially emerged at the same time. They are the oldest visible objects in the universe. Globular clusters come together in dense, spherical volumes with diameters hundreds of times smaller than the diameter of our galaxy. The Milky Way is surrounded by about 150 globular clusters, some of which are visible in the darkness of the night; but about ten or twenty thousand globular clusters can be found around the giant galaxies located at the centre of the galaxy clusters. Galaxy clusters contain hundreds or thousands of galaxies bound together by gravity and infused by hot gas (over ten times hotter than that at the Sun's core).

These globular clusters are thought to have formed shortly after the birth of the universe about 13,800 million years ago, at the same time or even before the first galaxies formed. Since then, they have remained largely unchanged apart from the ageing of all their stars and the gradual death of most of the remaining stars.

Nature Astronomy

Thomas Broadhurst, the Ikerbasque Research Professor at the UPV/EHU's Department of Theoretical Physics and History of Science, explained that "it is not fully understood why the brightest galaxies form in the centre of the galaxy clusters. The fact that they contain thousands of old globular clusters may be a point to take into consideration." A study led by Dr Lim of the University of Hong Kong and published by the prestigious journal Nature Astronomy, and in which Broadhurst collaborated, has found unexpected answers to the origin of some globular clusters located around the giant galaxies at the centre of galaxy clusters: "We discovered that thousands of new globular clusters have been forming over the last billion years out of a cool gas in the giant galaxy located in the centre of the Perseus galaxy cluster," explained Prof Broadhurst.

The younger globular clusters are closely associated with, and therefore formed from, a complex network of cool gas that extends to the outer reaches of the giant galaxy. This network of cool gas precipitates from the hot gas that infuses the entire Perseus galaxy cluster; in fact, the gas concentrates in the centre allowing it to cool faster and that leads to the creation of globular clusters. Once formed, these infant globular clusters do not remain in the network of cool gas and rain inwards onto the giant galaxy like raindrops falling from the clouds. "So," explained Broadhurst, "one could expect that the central galaxies of these clusters will grow in brightness over cosmic time as a result of the rain of globular clusters they receive from the gas that surrounds them".
-end-
Additional information

The study was led by Dr Lim and Emily Wong at the Department of Physics of the University of Hong Kong, and had the collaboration of the Ikerbasque Research Professor of the UPV/EHU Thomas Broadhurst, Dr Youichi Ohyama of the Institute of Astronomy and Astrophysics of Taiwan, and Dr Elinor Medezinski of the University of Princeton. Data provided by the Hubble Space Telescope were used for the study.

Bibliographical reference

Jeremy Lim, Emily Wong, Youichi Ohyama, Tom Broadhurst, Elinor Medezinski

Sustained formation of progenitor globular clusters in a giant elliptical Galaxy
Nature Astronomy (2019)
DOI: 10.1038/s41550-019-0909-6

University of the Basque Country

Related Globular Clusters Articles:

Small quake clusters can't hide from AI
A deep learning algorithm developed at Rice University analyzes data from a deadly landslide in Greenland to show how it may someday predict seismic events like earthquakes and volcanic eruptions.
Discovered: Remnant of ancient globular cluster that's "the last of its kind"
A team of astronomers discovered a stellar stream composed of the remnants of an ancient globular cluster that was torn apart by the Milky Way's gravity 2 billion years ago, when Earth's most-complex lifeforms were single-celled organisms.
Countries group into clusters as COVID-19 outbreak spreads
Mathematicians based in Australia and China have developed a method to analyze the large amount of data accumulated during the COVID-19 pandemic.
Exploring mass dependence in electron-hole clusters
A study published in EPJ B reveals that the behaviour of one type of three-particle cluster displays a distinct relationship with the ratio between the masses of its particles.
Age of NGC 6652 globular cluster specified
Senior Research Associate Margarita Sharina (Special Astrophysical Observatory) and Associate Professor Vladislav Shimansky (Kazan Federal University) studied the globular cluster NGC 6652.4.05957 and found out that its age is close to 13.6 billion years, which makes it one of the oldest objects in the Milky Way.
Study identifies regional malnutrition clusters across India
Childhood malnutrition in India remains a major problem. A new study shows that the problem is concentrated in specific geographic areas, which could help policymakers working to address the issue.
New aspects of globular glial tauopathy could help in the design of more effective drugs
This study, led by Dr. Isidre Ferrer, has described that protein inclusions that damage neurons and glial cells are responsible for the pathology showed by globular glial tauopathy patients.
How fruit flies flock together in orderly clusters
Opposing desires to congregate and maintain some personal space drive fruit flies to form orderly clusters, according to a study published today in eLife.
Clusters of gold atoms form peculiar pyramidal shape
Freestanding clusters of twenty gold atoms take the shape of a pyramid, researchers discovered.
HKU astronomy research team unveils one origin of globular clusters around giant galaxies
A study led by Dr Jeremy Lim and his Research Assistant, Miss Emily Wong, at the Department of Physics of The University of Hong Kong (HKU), utilizing data from the Hubble Space Telescope, has provided surprising answers to the origin of some globular clusters around giant galaxies at the centers of galaxy clusters.
More Globular Clusters News and Globular Clusters Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Debbie Millman: Designing Our Lives
From prehistoric cave art to today's social media feeds, to design is to be human. This hour, designer Debbie Millman guides us through a world made and remade–and helps us design our own paths.
Now Playing: Science for the People

#574 State of the Heart
This week we focus on heart disease, heart failure, what blood pressure is and why it's bad when it's high. Host Rachelle Saunders talks with physician, clinical researcher, and writer Haider Warraich about his book "State of the Heart: Exploring the History, Science, and Future of Cardiac Disease" and the ails of our hearts.
Now Playing: Radiolab

Insomnia Line
Coronasomnia is a not-so-surprising side-effect of the global pandemic. More and more of us are having trouble falling asleep. We wanted to find a way to get inside that nighttime world, to see why people are awake and what they are thinking about. So what'd Radiolab decide to do?  Open up the phone lines and talk to you. We created an insomnia hotline and on this week's experimental episode, we stayed up all night, taking hundreds of calls, spilling secrets, and at long last, watching the sunrise peek through.   This episode was produced by Lulu Miller with Rachael Cusick, Tracie Hunte, Tobin Low, Sarah Qari, Molly Webster, Pat Walters, Shima Oliaee, and Jonny Moens. Want more Radiolab in your life? Sign up for our newsletter! We share our latest favorites: articles, tv shows, funny Youtube videos, chocolate chip cookie recipes, and more. Support Radiolab by becoming a member today at Radiolab.org/donate.