Deep imaging suggests isolated galaxy forms stars without signs of past mergers

-

 



Using the Two-meter Twin Telescope (TTT3), Spanish astronomers have conducted deep optical imaging of an isolated dwarf galaxy known as NGC 6789. Results of the new observations, presented November 10 on the arXiv preprint server, shed more light on the star formation process in this galaxy.

Isolated but forming stars

Discovered in 1883, NGC 6789 is a blue compact dwarf (BCD) galaxy located some 12 million light years away in the Local Void-a region of space with far fewer galaxies than its surroundings. However, despite its extreme isolation, NGC 6789 shows recent central star formation activity.

Previous observations of NGC 6789 have found that approximately 4% of its total stellar mass—about 100 million solar masses-formed within the past 600 million years. It turned out that the central star-forming region of this galaxy is embedded within an apparently undisturbed, redder elliptical outer structure.

One question remains unanswered

Therefore, what still baffles scientists is the source of the gas sustaining recent star formation in NGC 6789, given that the galaxy is isolated and showcases an undisturbed shape.

To address this question, a team of astronomers led by Ignacio Trujillo of the University of La Laguna in Spain, has employed TTT3 to perform deeper optical observations of NGC 6789 than previously conducted.

"We present substantially deeper multiband imaging of NGC 6789 to explore its outer regions and search for faint features that may reveal evidence of past minor mergers or gas accretion events capable of supplying the fuel required to build its star-forming core," the researchers explained.

The new observations found that NGC 6789 maintains its elliptical shape down to the brightness of about 30 mag/arcsec2 (in g-band), or to a radial distance of 1.5 arcminutes, and that it exhibits a significant color gradient due to its central star-forming region. Therefore, no evidence of tidal features or merger remnants was found.

Furthermore, the collected data allowed the astronomers to place an upper limit on the amount of stellar mass that could potentially surround NGC 6789 as a result of the disruption of any small satellite. This value was calculated to be approximately 200,000 solar masses.

The researchers underlined that the number of new stars in the central region of NGC 6789 is around 4 million solar masses. Thus, they assume that the absence of any visible stellar streams around the galaxy indicates that its central starburst is either internally originated or produced by the recent infall of pristine gas.

"Its recent central star formation was likely produced either by in-situ residual gas or by the accretion of external pristine gas not associated with a minor merging activity," the authors of the paper explained.

Website: ac.sciencefather.com

Nomination link:
https://academicawards.sciencefather.com/award-nomination/?ecategory=Awards&rcategory=Awardee

Contact us: academic@sciencefather.com

Get connected Here:

You Tube: http://www.youtube.com/@academicawards
Facebook: https://www.facebook.com/profile.php?id=100093671170511
Instagram: https://www.youtube.com/channel/UCM-OlZD0B3uvxFE2dEITMhg
Linkedin: https://www.linkedin.com/in/harita-r-1b9861224/
YouTube: https://www.youtube.com/channel/UCM-OlZD0B3uvxFE2dEITMhg

#sciencefather
#academicawards
#isolatedgalaxy
#starformation
#nomergers
#galaxyevolution
#astronomydiscovery
#cosmicstructure
#spaceobservations
#astrophysics
#universeexploration

Comments

Post a Comment

Popular posts from this blog

Using plasma technology to recycle CO₂ from steelmaking

-
Image
Plasma is all around us, comprising 99% of the visible universe, including the stars at night and the branch of lightning we see cracking open the sky. Researchers are using the power of this superheated matter for everything from making computer chips to healing wounds. And in Belgium, three companies are collaborating on a world-first technology: a plasma reactor that turns captured CO₂ into carbon monoxide (CO) for steel and chemical production. The process holds promise for decarbonizing steelmaking. The role of CO₂ recycling The steel sector creates more CO₂ than any other heavy industry and is considered challenging to electrify. This is because traditional steelmaking in blast furnaces uses coal as both a source of heat and, in the chemical process, as a reductant for converting iron ore to elemental (‘pig’) iron. While the sector looks to future-proof with technologies such as electric arc furnaces and direct reduction of iron ore with hydrogen, it is looking to CO₂ capture, ut...
Read more

US Technology Leaders Tap NVIDIA AI Software to Transform World’s Industries

-
Image
U.S. technology leaders tap NVIDIA AI software to transform industries worldwide. AT&T, Lowe’s, University of Florida Among First Organizations Using NVIDIA NeMo Accenture, Deloitte, Quantiphi, SoftServe Tap NVIDIA NeMo, NIM Microservices and NIM Agent Blueprints to Create Custom Generative AI Agents for Clients Cloudera, DataStax, Google Cloud, NetApp, SAP, ServiceNow, Teradata Advance Data and AI Platforms With NIM NVIDIA AI Summit — NVIDIA today announced it is teaming with U.S. technology leaders to help organizations create custom AI applications and transform the world’s industries using the latest NVIDIA NIM™ Agent Blueprints and NVIDIA NeMo™ and NVIDIA NIM microservices. Across industries, organizations like AT&T, Lowe’s and the University of Florida are using the microservices to create their own data-driven AI flywheels to power custom generative AI applications. U.S. technology consulting leaders Accenture, Deloitte, Quantiphi and SoftServe are adopting NVIDIA NIM Ag...
Read more

Astronomers prepare for once-in-a-lifetime event: A 'new star' in the night sky

-
Image
Stargazers and astronomers around the world continue to gaze toward the Corona Borealis constellation 3,000 light-years from Earth, where a long-dead star is expected to reignite in an explosion so powerful it will briefly rival the brilliance of Polaris, the North Star. The stellar corpse last turned on almost 80 years ago and will not reignite for another 80 years, making this a nearly once-in-a-lifetime experience . Already, the stellar remnant, a white dwarf called T Coronae Borealis that's feasting on material from a nearby red giant star, has revealed a tell-tale dip in brightness that "is right on top" of the one that preceded its previous outburst in 1946. Astronomers don't yet know for sure what's causing the dip, but they say it's just a matter of time before the nova satiates its hunger and explodes into a spectacular nova. "We know it's going to go off — it's very obvious," Edward Sion, a professor of astronomy and astrophysics at...
Read more