Showing posts with label Triangulum Galaxy. Show all posts
Showing posts with label Triangulum Galaxy. Show all posts

Monday, March 11, 2024

Peering Into the Tendrils of NGC 604 with NASA's Webb

NGC 604 (NIRCam Image)
Credits: Image: NASA, ESA, CSA, STScI

NGC 604 (MIRI Image)
Credits: Image: NASA, ESA, CSA, STScI



The formation of stars and the chaotic environments they inhabit is one of the most well-studied, but also mystery-shrouded, areas of cosmic investigation. The intricacies of these processes are now being unveiled like never before by NASA’s James Webb Space Telescope.

Two new images from Webb’s NIRCam (Near-Infrared Camera) and MIRI (Mid-Infrared Instrument) showcase star-forming region NGC 604, located in the Triangulum galaxy (M33), 2.73 million light-years away from Earth. In these images, cavernous bubbles and stretched-out filaments of gas etch a more detailed and complete tapestry of star birth than seen in the past.

Sheltered among NGC 604’s dusty envelopes of gas are more than 200 of the hottest, most massive kinds of stars, all in the early stages of their lives. These types of stars are B-types and O-types, the latter of which can be more than 100 times the mass of our own Sun. It’s quite rare to find this concentration of them in the nearby universe. In fact, there’s no similar region within our own Milky Way galaxy.

This concentration of massive stars, combined with its relatively close distance, means NGC 604 gives astronomers an opportunity to study these objects at a fascinating time early in their life.

In Webb’s near-infrared NIRCam image, the most noticeable features are tendrils and clumps of emission that appear bright red, extending out from areas that look like clearings, or large bubbles in the nebula. Stellar winds from the brightest and hottest young stars have carved out these cavities, while ultraviolet radiation ionizes the surrounding gas. This ionized hydrogen appears as a white and blue ghostly glow.

The bright orange-colored streaks in the Webb near-infrared image signify the presence of carbon-based molecules known as polycyclic aromatic hydrocarbons, or PAHs. This material plays an important role in the interstellar medium and the formation of stars and planets, but its origin is a mystery. As you travel farther from the immediate clearings of dust, the deeper red signifies molecular hydrogen. This cooler gas is a prime environment for star formation.

Webb’s exquisite resolution also provides insights into features that previously appeared unrelated to the main cloud. For example, in Webb’s image, there are two bright, young stars carving out holes in dust above the central nebula, connected through diffuse red gas. In visible-light imaging from NASA’s Hubble Space Telescope, these appeared as separate splotches.

Webb’s view in mid-infrared wavelengths also illustrates a new perspective into the diverse and dynamic activity of this region. In the MIRI view of NGC 604, there are noticeably fewer stars. This is because hot stars emit much less light at these wavelengths, while the larger clouds of cooler gas and dust glow. Some of the stars seen in this image, belonging to the surrounding galaxy, are red supergiants – stars that are cool but very large, hundreds of times the diameter of our Sun. Additionally, some of the background galaxies that appeared in the NIRCam image also fade. In the MIRI image, the blue tendrils of material signify the presence of PAHs.

NGC 604 is estimated to be around 3.5 million years old. The cloud of glowing gases extends to some 1,300 light-years across.

The James Webb Space Telescope is the world's premier space science observatory. Webb is solving mysteries in our solar system, looking beyond to distant worlds around other stars, and probing the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and the Canadian Space Agency.




About This Release

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Media Contact:

Hannah Braun
Space Telescope Science Institute, Baltimore, Maryland

Christine Pulliam
Space Telescope Science Institute, Baltimore, Maryland

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Contact Us: Direct inquiries to the News Team.


Friday, November 19, 2021

Astronomical object found by amateur identified as new dwarf galaxy


The newly discovered dwarf galaxy may be a satellite of the Triangulum galaxy, which would reassure experts that their theories around how galaxies are formed are correct. Credit: Giuseppe Donatiello


Astrophysicists at the University of Surrey and the Instituto de Astrofísica de Andalucía have identified a speck in the sky found by an amateur astronomer as a ground-breaking new dwarf galaxy called Pisces VII/ Tri III.

Enthusiast Giuseppe Donatiello spotted the galaxy while scrutinising publicly available data and his finding was investigated by professional astrophysicists, led by Dr. David Martinez-Delgado from the Instituto de Astrofisica de Andalucia, who used deeper images taken with the Telescopio Nazionale Galileo. By processing the data and performing photometric calibration, they confirmed the finding is a new dwarf galaxy, but they need further images from even more powerful telescopes to confirm its precise location and significance.

Their analysis has identified Pisces VII/ Tri III as one of two things, either of which would make it an important astrophysical discovery. The team’s calculations show it is either an isolated dwarf galaxy, or it is a satellite of the Triangulum galaxy (M33). If it is isolated, it is thought to be the faintest field galaxy ever detected. If it is a satellite of M33, it could reassure experts that their theories around how galaxies are formed are correct.

Emily Charles, a PhD student at the University of Surrey who worked on the project, said:

“Theoretical knowledge about galaxy formation means we’d expect to see many more little galaxies orbiting the Triangulum galaxy, M33. However, so far it only has one known satellite. If this newly identified galaxy does belong to M33, it might imply that there are many more that haven’t been uncovered yet as they are too faint to show up in previous surveys of the system. M33 currently challenges astrophysicists’ assumptions, but this new finding starts reassuring us that our theories are correct.”

In order to confirm whether Pisces VII/ Tri III is isolated or an M33 satellite, the team needs to accurately measure the distance to the galaxy and see how it is moving compared to M33. Both require further imaging using other telescopes.

Noushin Karim, another PhD student at the University of Surrey who helped identify Pisces VII/ Tri III, said:

“Deep imaging from Hubble would allow us to reach fainter stars which act as more robust distance estimators, as they have a standard brightness. To confirm the new galaxy’s movement, we need imaging from an 8m or 10m telescope, like Keck or Gemini.”

A paper explaining their work and how they came to their conclusions is published in the peer-reviewed journal, Monthly Notices of the Royal Astronomical Society (MNRAS). Next the team will apply for access to other telescopes in order to continue their analysis.

Read the full paper: “Pisces VII: discovery of a possible satellite of Messier 33 in the DESI legacy imaging surveys” Monthly Notices of the Royal Astronomical Society, Volume 509, Issue 1, January 2022, https://doi.org/10.1093/mnras/stab2797




Monday, February 11, 2019

Gaia clocks new speeds for Milky Way Andromeda collision

Copyright Orbits: E. Patel, G. Besla (University of Arizona), R. van der Marel (STScI);
Images: ESA (Milky Way); ESA/Gaia/DPAC (M31, M33) 

ESA’s Gaia satellite has looked beyond our Galaxy and explored two nearby galaxies to reveal the stellar motions within them and how they will one day interact and collide with the Milky Way – with surprising results. 

Our Milky Way belongs to a large gathering of galaxies known as the Local Group and, along with the Andromeda and Triangulum galaxies – also referred to as M31 and M33, respectively – makes up the majority of the group’s mass. 

Astronomers have long suspected that Andromeda will one day collide with the Milky Way, completely reshaping our cosmic neighbourhood. However, the three-dimensional movements of the Local Group galaxies remained unclear, painting an uncertain picture of the Milky Way’s future.


Copyright: ESA/Gaia/DPAC, CC BY-SA 3.0 IGO
 
“We needed to explore the galaxies’ motions in 3D to uncover how they have grown and evolved, and what creates and influences their features and behaviour,” says lead author Roeland van der Marel of the Space Telescope Science Institute in Baltimore, USA.  

“We were able to do this using the second package of high-quality data released by Gaia.”

Gaia is currently building the most precise 3D map of the stars in the nearby Universe, and is releasing its data in stages. The data from the second release, made in April 2018, was used in this research. 

Previous studies of the Local Group have combined observations from telescopes including the NASA/ESA Hubble Space Telescope and the ground-based Very Long Baseline Array to figure out how the orbits of Andromeda and Triangulum have changed over time. The two disc-shaped spiral galaxies are located between 2.5 and 3 million light-years from us, and are close enough to one another that they may be interacting. 

Two possibilities emerged: either Triangulum is on an incredibly long six-billion-year orbit around Andromeda but has already fallen into it in the past, or it is currently on its very first infall. Each scenario reflects a different orbital path, and thus a different formation history and future for each galaxy.

Copyright: NASA, ESA, and M. Durbin, J. Dalcanton, and B. F. Williams (University of Washington); CC BY 4.0

While Hubble has obtained the sharpest view ever of both Andromeda and Triangulum, Gaia measures the individual position and motion of many of their stars with unprecedented accuracy.
“We combed through the Gaia data to identify thousands of individual stars in both galaxies, and studied how these stars moved within their galactic homes,” adds co-author Mark Fardal, also of Space Telescope Science Institute. 

“While Gaia primarily aims to study the Milky Way, it’s powerful enough to spot especially massive and bright stars within nearby star-forming regions – even in galaxies beyond our own.” 

The stellar motions measured by Gaia not only reveal how each of the galaxies moves through space, but also how each rotates around its own spin axis. 

A century ago, when astronomers were first trying to understand the nature of galaxies, these spin measurements were much sought-after, but could not be successfully completed with the telescopes available at the time.

Copyright: ESA/Gaia (star motions); NASA/Galex (background image); R. van der Marel, M. Fardal, J. Sahlmann (STScI)
“It took an observatory as advanced as Gaia to finally do so,” says Roeland.

“For the first time, we’ve measured how M31 and M33 rotate on the sky. Astronomers used to see galaxies as clustered worlds that couldn’t possibly be separate ‘islands’, but we now know otherwise.
“It has taken 100 years and Gaia to finally measure the true, tiny, rotation rate of our nearest large galactic neighbour, M31. This will help us to understand more about the nature of galaxies.” 

By combining existing observations with the new data release from Gaia, the researchers determined how Andromeda and Triangulum are each moving across the sky, and calculated the orbital path for each galaxy both backwards and forwards in timefor billions of years. 
 
“The velocities we found show that M33 cannot be on a long orbit around M31,” says co-author Ekta Patel of the University of Arizona, USA. “Our models unanimously imply that M33 must be on its first infall into M31.” 

While the Milky Way and Andromeda are still destined to collide and merge, both the timing and destructiveness of the interaction are also likely to be different than expected.  

As Andromeda’s motion differs somewhat from previous estimates, the galaxy is likely to deliver more of a glancing blow to the Milky Way than a head-on collision. This will take place not in 3.9 billion years’ time, but in 4.5 billion – some 600 million years later than anticipated.

Copyright:  NASA, ESA, J. Dalcanton (University of Washington, USA), B. F. Williams (University of Washington, USA), L. C. Johnson (University of Washington, USA), the PHAT team, and R. Gendler.

“This finding is crucial to our understanding of how galaxies evolve and interact,” says Timo Prusti, ESA Gaia Project Scientist.

“We see unusual features in both M31 and M33, such as warped streams and tails of gas and stars. If the galaxies haven’t come together before, these can’t have been created by the forces felt during a merger. Perhaps they formed via interactions with other galaxies, or by gas dynamics within the galaxies themselves. 

“Gaia was designed primarily for mapping stars within the Milky Way — but this new study shows that the satellite is exceeding expectations, and can provide unique insights into the structure and dynamics of galaxies beyond the realm of our own. The longer Gaia watches the tiny movements of these galaxies across the sky, the more precise our measurements will become.”



Notes for Editors

First Gaia Dynamics of the Andromeda System: DR2 Proper Motions, Orbits, and Rotation of M31 and M33” by R. P. van der Marel et al. is published in Astrophysical Journal

ESA’s Gaia satellite was launched in 2013 to create the most precise three-dimensional map of one billion of the stars within the Milky Way. The mission has released two lots of data so far: Gaia Data Release 1 on 14 September 2016, and Gaia Data Release 2 on 25 April 2018 (the latter of which was used in this study). More releases will follow in coming years.



Contacts

Roeland P. van der Marel
Space Telescope Science Institute
Baltimore, USA
Email: marel@stsci.edu

Mark Fardal
Space Telescope Science Institute
Baltimore, USA
Email: fardal@stsci.edu

Ekta Patel
Steward Observatory
University of Arizona, USA
Email: ektapatel@email.arizona.edu

Timo Prusti
ESA Gaia Project Scientist
Email: tprusti@cosmos.esa.int

Markus Bauer
ESA Science Programme Communication Officer
Tel: +31 71 565 6799
Mob: +31 61 594 3 954
Email: markus.bauer@esa.int

Source: ESA/GAIA


Tuesday, January 08, 2019

Hubble takes gigantic image of the Triangulum Galaxy

The sharpest view ever of the Triangulum Galaxy

NGC 604 — a gigantic gas cloud in the Triangulum Galaxy

NGC 595 — a diffuse nebula in the Triangulum Galaxy

Stellar association IC 142

Wide-field view of the Triangulum Galaxy showing the extent of the survey

Area around the Triangulum Galaxy (ground-based image)



Videos

Hubblecast 115 Light: Triangulum Galaxy in unrivalled detail
Hubblecast 115 Light: Triangulum Galaxy in unrivalled detail

Zooming in on the Triangulum Galaxy
Zooming in on the Triangulum Galaxy

A close-up look at the Triangulum Galaxy
A close-up look at the Triangulum Galaxy



The NASA/ESA Hubble Space Telescope has captured the most detailed image yet of a close neighbour of the Milky Way — the Triangulum Galaxy, a spiral galaxy located at a distance of only three million light-years. This panoramic survey of the third-largest galaxy in our Local Group of galaxies provides a mesmerising view of the 40 billion stars that make up one of the most distant objects visible to the naked eye.

This new image of the Triangulum Galaxy — also known as Messier 33 or NGC 598 — has a staggering 665 million pixels and showcases the central region of the galaxy and its inner spiral arms. To stitch together this gigantic mosaic, Hubble’s Advanced Camera for Surveys needed to create 54 separate images.

Under excellent dark-sky conditions, the Triangulum Galaxy can be seen with the naked eye as a faint, blurry object in the constellation of Triangulum (the Triangle), where its ethereal glow is an exciting target for amateur astronomers.

At only three million light-years from Earth, the Triangulum Galaxy is a notable member of the Local Group — it is the group’s third-largest galaxy, but also the smallest spiral galaxy in the group [1]. It measures only about 60 000 light-years across, compared to the 200 000 light-years of the Andromeda Galaxy; the Milky Way lies between these extremes at about 100 000 light-years in diameter [2].

The Triangulum Galaxy is not only surpassed in size by the other two spirals, but by the multitude of stars they contain. The Triangulum Galaxy has at least an order of magnitude less stars than the Milky Way and two orders of magnitude less than Andromeda. These numbers are hard to grasp when already in this image 10 to 15 million individual stars are visible.

In contrast to the two larger spirals, the Triangulum Galaxy doesn’t have a bright bulge at its centre and it also lacks a bar connecting its spiral arms to the centre. It does, however, contain a huge amount of gas and dust, giving rise to rapid star formation. New stars form at a rate of approximately one solar mass every two years.

The abundance of gas clouds in the Triangulum Galaxy is precisely what drew astronomers to conduct this detailed survey. When stars are born, they use up material in these clouds of gas and dust, leaving less fuel for new stars to emerge. Hubble’s image shows two of the four brightest of these regions in the galaxy: NGC 595 and NGC 604. The latter is the second most luminous region of ionised hydrogen within the Local Group and it is also among the largest known star formation regions in the Local Group.

These detailed observations of the Triangulum Galaxy have tremendous legacy value — combined with those of the Milky Way, the Andromeda Galaxy and the irregular Magellanic Cloud galaxies, they will help astronomers to better understand star formation and stellar evolution.



Notes

[1] Our galaxy, the Milky Way, is part of the Local Group, an assembly of more than 50 galaxies bound together by gravity. Its largest member is the Andromeda Galaxy — also known as Messier 31 — followed by the Milky Way and the Triangulum Galaxy. The remaining members of the Local Group are dwarf galaxies, each orbiting one of the three larger ones. 


[2] The much bigger Andromeda Galaxy was mapped by Hubble in 2015, creating the sharpest and largest image of this galaxy and the largest Hubble image ever (heic1502).



Links



Contact 

Mathias Jäger
ESA/Hubble, Public Information Officer
Garching, Germany
Tel: +49 176 62397500
Email:
mjaeger@partner.eso.org

Source: ESA/Hubble/News