Stellar parenting: Making new stars by 'adopting' stray cosmic gases

January 27, 2016
This is a portrait of the massive globular cluster NGC 1783 in the Large Magellanic Cloud, taken by the Hubble Space Telescope. This dense swarm of stars is located about 160,000 light years from Earth and has the mass of about 170,000 Suns. A new study by astronomers from the Kavli Institute for Astronomy and Astrophysics at Peking University (KIAA), the National Astronomical Observatories of the Chinese Academy of Sciences (NAOC), Northwestern University and the Adler Planetarium suggests the globular cluster swept up stray gas and dust from outside the cluster to give birth to three different generations of stars. Credit: ESA/Hubble and NASA. Acknowledgement: Judy Schmidt (geckzilla.com)

Among the most striking objects in the universe are glittering, dense swarms of stars known as globular clusters. Astronomers had long thought globular clusters formed their millions of stars in bulk at around the same time, with each cluster's stars having very similar ages, much like twin brothers and sisters. Yet recent discoveries of young stars in old globular clusters have scrambled this tidy picture.

Instead of having all their stellar progeny at once, globular clusters can somehow bear second or even third sets of thousands of sibling stars. Now a new study led by researchers at the Kavli Institute for Astronomy and Astrophysics (KIAA) at Peking University, and including astronomers at Northwestern University, the Adler Planetarium and the National Astronomical Observatories of the Chinese Academy of Sciences (NAOC), might explain these puzzling, successive stellar generations.

Using observations by the Hubble Space Telescope, the research team has for the first time found young populations of stars within globular clusters that have apparently developed courtesy of star-forming gas flowing in from outside of the clusters themselves. This method stands in contrast to the conventional idea of the clusters' initial stars shedding gas as they age in order to spark future rounds of star birth.

The study will be published in the Jan. 28 issue of the journal Nature.

"This study offers new insight on the problem of multiple stellar populations in ," said study lead author Chengyuan Li, an astronomer at KIAA and NAOC who also is affiliated with the Chinese Academy of Sciences' Purple Mountain Observatory. "Our study suggests the gaseous fuel for these new stellar populations has an origin that is external to the cluster, rather than internal."

In a manner of speaking, globular clusters appear capable of "adopting" baby stars—or at least the material with which to form new stars—rather than creating more "biological" children as parents in a human family might choose to do.

"Our explanation that secondary stellar populations originate from gas accreted from the clusters' environments is the strongest alternative idea put forward to date," said Richard de Grijs, also an astronomer at KIAA and Chengyuan's Ph.D. advisor. "Globular clusters have turned out to be much more complex than we once thought."

Globular clusters are spherical, densely packed groups of stars orbiting the outskirts of galaxies. Our home galaxy, the Milky Way, hosts several hundred. Most of these local, massive clusters are quite old, however, so the KIAA-led research team turned their attention to young and intermediate-aged clusters found in two nearby dwarf galaxies, collectively called the Magellanic Clouds.

Specifically, the researchers used Hubble observations of the globular clusters NGC 1783 and NGC 1696 in the Large Magellanic Cloud, along with NGC 411 in the Small Magellanic Cloud. Scientists routinely infer the ages of stars by looking at their colors and brightnesses. Within NGC 1783, for example, Li, de Grijs and colleagues identified an initial population of stars aged 1.4 billion years, along with two newer populations that formed 890 million and 450 million years ago.

What is the most straightforward explanation for these unexpectedly differing stellar ages? Some globular clusters might retain enough gas and dust to crank out multiple generations of stars, but this seems unlikely, said study co-author Aaron M. Geller of Northwestern University and the Adler Planetarium in Chicago.

"Once the most massive stars form, they are like ticking time bombs, with only about 10 million years until they explode in powerful supernovae and clear out any remaining gas and dust," Geller said. "Afterwards, the lower-mass stars, which live longer and die in less violent ways, may allow the cluster to build up gas and dust once again."

The KIAA-led research team proposes that globular clusters can sweep up stray gas and dust they encounter while moving about their respective host galaxies. The theory of newborn stars arising in clusters as they "adopt" interstellar gases actually dates back to a 1952 paper. More than a half-century later, this once speculative idea suddenly has key evidence to support it.

In the study, the KIAA researchers analyzed Hubble observations of these star clusters, and then Geller and his Northwestern colleague Claude-André Faucher-Giguère carried out calculations that show this theoretical explanation is possible in the globular clusters this team studied.

"We have now finally shown that this idea of clusters forming new with accreted gas might actually work," de Grijs said, "and not just for the three clusters we observed for this study, but possibly for a whole slew of them."

Future studies will aim to extend the findings to other Magellanic Cloud as well as Milky Way .

Explore further: Image: Hubble checks out a home for old stars

More information: Formation of new stellar populations from gas accreted by massive young star clusters, Nature, nature.com/articles/doi:10.1038/nature16493

Related Stories

Image: Hubble checks out a home for old stars

December 21, 2015

This image, taken with the Wide Field Planetary Camera 2 on board the NASA/ESA Hubble Space Telescope, shows the globular cluster Terzan 1. Lying around 20,000 light-years from us in the constellation of Scorpius (The Scorpion), ...

Image: Hubble sees a youthful cluster

August 31, 2015

Shown here in a new image taken with the Advanced Camera for Surveys (ACS) on board the NASA/ESA Hubble Space Telescope is the globular cluster NGC 1783. This is one of the biggest globular clusters in the Large Magellanic ...

Hubble views a galactic mega-merger

January 18, 2016

The subject of this NASA/ESA Hubble Space Telescope image is known as NGC 3597. It is the product of a collision between two good-sized galaxies, and is slowly evolving to become a giant elliptical galaxy. This type of galaxy ...

Fossil star clusters reveal their age

July 27, 2015

Using a new age-dating method, an international team of astronomers has determined that ancient star clusters formed in two distinct epochs – the first 12.5 billion years ago and the second 11.5 billion years ago.

Recommended for you

Astronomers search for signs of life on Wolf 1061 exoplanet

January 19, 2017

Is there anybody out there? The question of whether Earthlings are alone in the universe has puzzled everyone from biologists and physicists to philosophers and filmmakers. It's also the driving force behind San Francisco ...

18 comments

Adjust slider to filter visible comments by rank

Display comments: newest first

Tuxford
1.2 / 5 (9) Jan 27, 2016
Scientists routinely infer the ages of stars by looking at their colors and brightnesses.


Using routine mainstream assumptions for the ages of stars. So given that, the merger maniacs must squirm for an explanation. Hence, we see the patch herein.

What is the most straightforward explanation for these unexpectedly differing stellar ages? Some globular clusters might retain enough gas and dust to crank out multiple generations of stars, but this seems unlikely


The most straightforward explanation is that the new gas is indeed from within, not without, as SQK theory predicts. And that the young stars are not so young, but instead are older having grown larger and experienced more accelerated internal growth therein by forming new non-metal material therein at a very rapid pace, leading to an accelerated deficit of metal concentration therein.

Or squirm and patch. Long live the fantasy!
wduckss
1.9 / 5 (9) Jan 27, 2016
Reluctant to comment on these articles, but neither Democritus would not be jealous of this text.

By the way, the color and shine have nothing to do with determining the age of stars.
jonesdave
3.4 / 5 (5) Jan 27, 2016
...as SQK theory predicts....


WTF is that? Got a link for any of it? Scientific ones, please.
katesisco
1.4 / 5 (13) Jan 27, 2016
I have learned more about astroscience reading Milton/DeGrazie than any of current nonsense theory. In wondering why the cloaking of 50 years of electrical universe science I have thought that it is ---unfortunately---due to economic manipulations that decreed we must profit from the free electrical input by first funneling it thru nuclear power plants. Which --unfortunately--we have failed to produce but in our hubris have spread radioactive poison everywhere on planet Earth.
The spreading of the nonsense that radioactivity is harmless, even beneficial, is a media smoothie generated for the US for the depleted uranium bombed areas of Europe and the Middle East.
As the drumbeat now is for natural gas ---new markets for compressed natural gas--one might suspect that in the future the diminished intelligence might eventually be connected to multiples of higher levels of carbon dioxide from our cars and furnaces much as the leaded gas led to autism and learning disabilities.
Bigbangcon
1.9 / 5 (9) Jan 27, 2016
"Yet recent discoveries of young stars in old globular clusters have scrambled this tidy picture."

Astronomers will always have "scrambled picture" and will continue to have this as long as they stick to their divine mantra that the universe is finite and expanding; that all matter/energy was created in one bang; that no new matter/antimatter is being created from the virtual particles of the quantum vacuum, particularly where matter concentration already exists; that there is no cosmic antimatter remaining after the primordial bang etc. etc.

The "scrambled picture" is actually simple and realistic if one gives up math-fuelled fantasy and looks at the universe the way Heraclitus saw it. The universe is an infinite and eternal (dynamic) living being, where continuously old matter (in the form of elementary particles) goes out of existence and new ones are formed from the quantum vacuum. http://www.amazon...40414445
Solon
1 / 5 (9) Jan 27, 2016
There is no proof that all those objects in the cluster are stars. There is no proof that even the nearest stars to us are really stars.
Tuxford
1.5 / 5 (8) Jan 27, 2016
...as SQK theory predicts....


WTF is that? Got a link for any of it? Scientific ones, please.

Old, but relevant: The universe is not expanding (1986).

http://cdsads.u-s...f4e25584

More Recent:

http://starburstf...l_G.html

And others, but only if truly interested. I think most prefer the fantasy. Be happy!

http://starburstf...archive/
Tuxford
1.1 / 5 (8) Jan 27, 2016
And here is a very recent paper which took LaViolette over 30 years to get published. It suggests the ice ages were triggered by a cosmic superwave event, emanating from our galactic core, and now illuminating the Crab nebula. Evidence was found from extraterrestrial deposits in the ice core record.

http://www.scienc...15006614

or

http://www.starbu...dust.pdf
jonesdave
3.9 / 5 (11) Jan 27, 2016
Ahh, La Violette! Stopped reading there. Thank you. Pseudoscientist. When I say links, I mean to something actually scientific. Proof would be good. Otherwise you are no further forward than the idiot Don Scott. And nobody takes him seriously.
jonesdave
4.1 / 5 (13) Jan 27, 2016
There is no proof that all those objects in the cluster are stars. There is no proof that even the nearest stars to us are really stars.


So they shouldn't have spectra that are anything like stars, yes? Would you mind providing a link to this particular nonsense; please? Or, like all EU devotees, are you just making sh*t up again?
jonesdave
3.9 / 5 (11) Jan 27, 2016
There is no proof that all those objects in the cluster are stars. There is no proof that even the nearest stars to us are really stars.


So they shouldn't have spectra that are anything like stars, yes? Would you mind providing a link to this particular nonsense; please? Or, like all EU devotees, are you just making sh*t up again?

ETA: Perhaps it's time to ask who these EU 'experts' are? Please lay it out. Who are they? What is their previous work? Where can we read it? Preferably in a scientific journal. Peer reviewed.
Otherwise, here's a thought; STFU.
Tuxford
1.6 / 5 (7) Jan 27, 2016
Ahh, La Violette! Stopped reading there. Thank you. Pseudoscientist. When I say links, I mean to something actually scientific. Proof would be good. Otherwise you are no further forward than the idiot Don Scott. And nobody takes him seriously.


So the Astrophysical Journal is not scientific?

So the International Journal of General Systems is not scientific?

So the Advances in Space Research is not scientific?

Whew. That was close! Back to the fantasy!

Pretend what you can't understand is not scientific, because otherwise, you would not be intellectually superior. Good going. Be happy! I won't be tempted by you again.
Phys1
4.3 / 5 (11) Jan 28, 2016
LaV refers to "Future discovery of these events in ice cores at other locations".
No decent referee should let that pass especially in an abstract.
Phys1
4.1 / 5 (13) Jan 28, 2016
There is no proof that all those objects in the cluster are stars. There is no proof that even the nearest stars to us are really stars.

Wow that is amazing!
Wait, you must be a crackpot.
joel in oakland
2.8 / 5 (4) Jan 28, 2016
"Adoption" seems like an odd metaphor. If one wants to trivialize the report in the name of being folksy, "scavenge" or "steal" quickly come to mind as better. Oh, but that might be disturbing, and we must be cutesy and folksy so that people aren't put off by that sciencey, complicated stuff. Awww - they're adopting. Isn't that cute?

Ugh.
Phys1
3 / 5 (6) Jan 28, 2016
@jio
What about "smoking stray cosmic gases"?
That could inspire the dudes !
Steelwolf
1.8 / 5 (5) Jan 31, 2016
So sorry that jonesdave and all of his alts have so much egg on their face. Seeing as how not only have some of La Violette's theories have been shown to be real and proven, as seen in articles too numerous to cite, but are here, in This Publication.

They support the idea that there is Plenty of 'Mass/Energy in the Universe, the Universe is Truly Infinite, which means that there is an Infinite amount of mass and we see only a very thin slice with things that were expected to exist at the quantum level Only can be seen as fractal iteration of what is going on in in matter from the quantum to the Cosmic levels, are starting to come in regularly now, if one takes off the blinders and just SEES what the evidence in front of them is pointing towards, taking all sources into consideration and removing those that are either too extreme or too intransigently 'conservative' in their modality of theoretical study to look outside of their own pressure cooker.

Degree? Einstein failed Math!
Vietvet
5 / 5 (4) Jan 31, 2016
"Einstein laughed. "I never failed in mathematics," he replied, correctly. "Before I was fifteen I had mastered differential and integral calculus." In primary school, he was at the top of his class and "far above the school requirements" in math. By age 12, his sister recalled, "he already had a predilection for solving complicated problems in applied arithmetic," and he decided to see if he could jump ahead by learning geometry and algebra on his own. His parents bought him the textbooks in advance so that he could master them over summer vacation. Not only did he learn the proofs in the books, he also tackled the new theories by trying to prove them on his own. He even came up on his own with a way to prove the Pythagorean theory."
http://content.ti...,00.html

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.