Showing posts with label Westerlund 2. Show all posts
Showing posts with label Westerlund 2. Show all posts

Saturday, March 21, 2026

Spring Collection: Spring Has Sprung in Space (As Always)

Westerlund 2 - NGC 346 - Cygnus OB3
Cat's Paw Nebula (NGC 6334) - Pelican Nebula (NGC 7000) - Flame Nebula (NGC 2024)

Visual Description: Spring Collection

This release features a series of composite images, each highlighting a different star-forming region, or "stellar nursery". The bright, colorful images are individually labeled, and presented in a three by two grid.

The first image, in the grid's upper left, features a young star cluster known as Westerlund 2. Here, scores of gleaming white specks ringed in neon pink are scattered across the image in a band that stretches from our lower right to our upper left, and beyond. The pink data represent stars seen with Chandra. Clouds of brick-orange dust enter the image from our lower left, and spread along the bottom edge of the frame.

Centered at the top of the grid is NGC 346, a star-forming region in the Small Magellanic Cloud. Here, tiny specks in golden orange, neon blue, and white, are scattered across a dark blue sky. Long streaks of hazy cloud coalesce on the left side of the image. A large, bright, neon pink X-ray cloud, seen with Chandra, hangs in the upper right.

In the upper right corner of the grid is Cygnus OB3, the most mature stellar nursery in the batch. Here, tiny white gleaming specks fill a black sky tinged with golden orange and silver haze. Several larger white spheres with faint outer rings in blues and greens dot the image, including a black hole and a massive star at the center of the frame.

In the second row of the grid, at our lower left, is a composite image of the Cat's Paw Nebula. Here, pockets of starry blue sky appear behind thick, overlapping rings of dark orange cloud. At the center of the image, tucked amongst the clouds, is a mottled patch of purple. This patch represents X-ray data gathered by Chandra. Centered at the bottom of the grid is the Pelican Nebula. Here, a hazy blue sky dotted with pink, white, and golden specks stretches across much of the frame. A dense, dark-orange cloud enters the composite image from lower right. Long, finger-like tendrils grow out of the cloud, as if reaching for distant baby stars.

And finally, at the lower righthand corner of the grid, is a composite image of the Flame Nebula. Here, a dense dusty-grey haze blankets the frame. Several dozen young stars light up the dust and gas cloud, white at the core with thick, neon purple-pink halos showing X-rays collected by Chandra.




  • This week, the Earth passes the point in its orbit when days in the northern hemisphere become longer than nights and spring begins.

  • This collection of spring-themed images is meant to celebrate the “flowering” that occurs throughout space.

  • There are six star-forming regions in these composite images, containing X-rays from Chandra and data from other telescopes.

  • The objects are NGC 7000 (aka, the Pelican Nebula), the Cat’s Paw Nebula, NGC 346, the Flame Nebula, Westerlund 2, and Cygnus OB3.



In the Northern Hemisphere this week, the calendar officially passes from winter into spring when the length of the day and the night become equal as the days become longer. Meanwhile, there are places in space where blooms of the stellar variety are always growing.

This collection of images from NASA’s Chandra X-ray Observatory and other telescopes contains regions where stars are forming. Often nicknamed “stellar nurseries,” they are cosmic gardens from which stars – not plants – emerge from the interstellar soil of gas and dust. X-rays are energetic enough that they can penetrate the gas and dust of these stellar nurseries, giving insight to the young stars and other high-energy phenomena that are happening within, including the effects of X-rays on any planets or planet-forming disks orbiting stars.

And, like gardens here on Earth, some stellar nurseries bloom before others. These images are listed roughly by their age, representing a span from “early” to “late spring,” cosmically speaking.

The Pelican Nebula (also known as NGC 7000) and the Cat’s Paw Nebula both contain stars that are mainly about a million years old. By comparison, the Sun is over 4.5 billion years old — or more than 4,000 times the age of these stars. In this new image of the Pelican Nebula, X-rays from Chandra (pink) are combined with an optical image from NASA’s Hubble Space Telescope (red, green, and blue). Meanwhile, the Cat’s Paw Nebula image has Chandra X-ray data (pink) overlaid on infrared data from NASA’s James Webb Space Telescope (red, orange, yellow, green, cyan and blue).

For stars that are slightly older — with ages between about one and three million years old — we look to NGC 346, the Flame Nebula, and Westerlund 2. For NGC 346, a star-forming region in the Small Magellanic Cloud, X-rays from Chandra (purple) are combined with an optical image from Hubble (red, green, and blue). In the Flame Nebula composite, Chandra’s X-rays (purple) are found throughout the gas and dust-filled landscape in infrared light seen by NASA’s James Webb Space Telescope (red, green, and blue). This Westerlund 2 image contains X-ray data from Chandra (purple) and infrared data from Webb (red, orange, green, cyan, and blue).

The most mature stars in these spring-themed images is the region around Cygnus X-1, a binary system where a black hole is partnered with a massive star. In this image of the Cygnus OB3 region, X-rays from Chandra (blue) are combined with optical data from Kitt Peak National Observatory (red and blue).

The companion star to the black hole in Cygnus X-1 is particularly interesting. Because it more than 20 times more massive than the Sun, it is likely going to explode in a supernova in the future. This event would seed the area with new elements that will become the cosmic soil for the next generation of stars.

This process of supernova explosions sending essential elements out into space will happen to many of the most massive stars in these stellar nurseries, underscoring the similar rhythms between the cycle of life here on Earth and the cycle of the stars across space.

NASA's Marshall Space Flight Center in Huntsville, Alabama, manages the Chandra program. The Smithsonian Astrophysical Observatory's Chandra X-ray Center controls science operations from Cambridge, Massachusetts, and flight operations from Burlington, Massachusetts.




Visual Description:

This release features a series of composite images, each highlighting a different star-forming region, or "stellar nursery". The bright, colorful images are individually labeled, and presented in a three by two grid.

The first image, in the grid's upper left, features a young star cluster known a Westerlund 2. Here, scores of gleaming white specks ringed in neon pink are scattered across the image in a band that stretches from our lower right to our upper left, and beyond. The pink data represent stars seen with Chandra. Clouds of brick-orange dust enter the image from our lower left, and spread along the bottom edge of the frame.

Centered at the top of the grid is NGC 346, a star-forming region in the Small Magellanic Cloud. Here, tiny specks in golden orange, neon blue, and white, are scattered across a dark blue sky. Long streaks of hazy cloud coalesce on the left side of the image. A large, bright, neon pink X-ray cloud, seen with Chandra, hangs in the upper right.

In the upper right corner of the grid is Cygnus OB3, the most mature stellar nursery in the batch. Here, tiny white gleaming specks fill a black sky tinged with golden orange and silver haze. Several larger white spheres with faint outer rings in blues and greens dot the image, including a black hole and a massive star at the center of the frame.

In the second row of the grid, at our lower left, is a composite image of the Cat's Paw Nebula. Here, pockets of starry blue sky appear behind thick, overlapping rings of dark orange cloud. At the center of the image, tucked amongst the clouds, is a mottled patch of purple. This patch represents X-ray data gathered by Chandra.

Centered at the bottom of the grid is the Pelican Nebula. Here, a hazy blue sky dotted with pink, white, and golden specks stretches across much of the frame. A dense, dark-orange cloud enters the composite image from lower right. Long, finger-like tendrils grow out of the cloud, as if reaching for distant baby stars.

And finally, at the lower righthand corner of the grid, is a composite image of the Flame Nebula. Here, a dense dusty-grey haze blankets the frame. Several dozen young stars light up the dust and gas cloud, white at the core with thick, neon purple-pink halos showing X-rays collected by Chandra.



Fast Facts for Westerlund 2:

Credit: X-ray: NASA/CXC/SAO/Sejong Univ./Hur et al; Infrared: ESA/Webb, NASA & CSA, V. Almendros-Abad, M. Guarcello, K. Monsch, and the EWOCS team. Image Processing: NASA/CXC/SAO/L. Frattare and K. Arcand
Release Date: March 19, 2026
Scale: Image is about 2.1 arcmin (12 light-years) across.
Category: Normal Stars & Star Clusters
Coordinates (J2000): RA: 10h 23m 58.60s | Dec: -57° 44' 40.62"
Constellation: Carina
Observation Date(s): 3 pointings from Aug 2003 to Sep 2006
Observation Time: 37 hours and 30 minutes (1 day 13 hours 30 minutes)
Obs. IDs: 3501, 6410, 6411
Instrument: ACIS
Color Code: X-ray: purple; Infrared: red, orange, green, cyan, and blue
Distance Estimate: About 20,000 light-years from Earth



Fast Facts for NGC 346:

Credit: X-ray: NASA/CXC/SAO; Optical: ESA/Hubble and NASA, A. Nota, P. Massey, E. Sabbi, C. Murray, M. Zamani (ESA/Hubble); Image Processing: NASA/CXC/SAO/L. Frattare
Release Date: March 19, 2026
Scale: Image is about 3.8 arcmin (220 light-years) across.
Category: Normal Stars & Star Clusters
Coordinates (J2000): RA: 00h 59m 05.1s | Dec: -72° 10' 33.2"
Constellation: Tucana
Observation Date(s): May 15, 2001
Observation Time: 27 hours 25 minutes (1 days 3 hours 25 minutes)
Obs. IDs: 1881
Instrument: ACIS
Color Code: X-ray: purple; Optical: red, green, and blue
Distance Estimate: About 200,000 light-years from Earth



Fast Facts for Cygnus OB3:

Credit: X-ray: NASA/CXC/SAO; Optical: T.A. Rector (University of Alaska Anchorage) and H. Schweiker (WIYN and NOIRLab/NSF/AURA). Image Processing: NASA/CXC/SAO/L. Frattare
Release Date: March 19, 2026
Scale: Image is about 26.5 arcmin (50 light-years) across.
Category: Normal Stars and Star Clusters & Black Holes
Coordinates (J2000): RA: 19h 58m 22s | Dec: +35° 12' 6"
Constellation: Cygnus
Observation Date(s): 3 observations from Jan 2002 to Apr 2003
Observation Time: 14 hours 18 minutes
Obs. IDs: 2742, 2743, 3814
Instrument: ACIS
Color Code: X-ray: blue; Optical: H-alpha: red, and Sulphur [S II]: blue
Distance Estimate: About 6,500 light-years from Earth



Fast Facts for Cat's Paw Nebula (NGC 6334):

Credit: X-ray: NASA/SAO/CXC; Infrared: NASA/ESA/CSA/STScI; Image Processing: NASA/CXC/SAO/J. Major
Release Date: March 19, 2026
Scale: Image is about 72 arcmin (91 light-years) across.
Category: Normal Stars and Star Clusters
Coordinates (J2000): RA: 5h 46m 45.8s | Dec: +0° 0′ 08.1"
Constellation: Scorpius
Observation Date(s): 10 observations from Aug 2002 to Jul 2016
Observation Time: 85 hours 28 minutes (3 days 13 hours 28 minutes)
Obs. IDs: 2573, 2574 ,3844, 4591, 8975, 12382, 13436, 18082, 18081, 18876
Instrument: ACIS
Color Code: X-ray: pink; Infrared: red, orange, yellow, green cyan, and blue
Distance Estimate: About 4,370 light-years from Earth



Fast Facts for Pelican Nebula (NGC 7000):

Credit: X-ray: NASA/CXC/SAO/F. Damiani; Optical: J. Bally/University of Colorado, B. Reipurth/University of Hawaii and NOIRLab/NSF/AURA; Image Processing: NASA/CXC/SAO/L. Frattare
Release Date: March 19, 2026
Scale: Image is about 19.3 arcmin (0.9 light-years) across.
Category: Normal Stars and Star Clusters
Coordinates (J2000): RA: 20h 50m 48s | Dec: +44° 21′ 0"
Constellation: Cygnus
Observation Date(s): 2 observations on Nov 20, 2012
Observation Time: 12 hours 6 minutes
Obs. IDs: 13647, 15592
Instrument: ACIS
Color Code:  X-ray: purple; Optical: red, green, and blue Distance Estimate: About 1,800 light-years from Earth



Fast Facts for Flame Nebula (NGC 2024):

Credit: X-ray: NASA/CXC/PSU/K. Getman, E. Feigelson, M. Kuhn & the MYStIX team; JWST Image: NASA, ESA, CSA,STScI, M. Meyer (University of Michigan), M. De Furio (UT Austin), M. Robberto (STScI), A. Pagan (STScI); Image Processing: NASA/CXC/SAO/L. Frattare

 

Release Date: March 19, 2026
Scale: Image is about 2.2 arcmin (1 light-years) across.
Category: Normal Stars and Star Clusters
Coordinates (J2000): RA: 05h 41m 46.30s | Dec: -01° 55′ 28.70"
Constellation: Orion
Observation Date(s): 1 observation Aug 2001
Observation Time: 20 hours 57 minutes
Obs. IDs: 1878
Instrument: ACIS
Color Code: X-ray: purple; Infrared: red, green, and blue
Distance Estimate: About 1,350 light-years from Earth


Saturday, January 24, 2026

Dwarf stars in a glittering sky

A cluster of stars inside a large nebula. The clouds of gas and dust are predominantly bright red in colour and wispy, akin to flames. They are clumped in the bottom-left corner. Other clouds, deeper in the cluster behind many of the stars, appear pale pink. The stars are concentrated in the top half of the image and are mostly small, bright white and six-pointed. They cast blue light over the nebula. Other stars with very long spikes surrounding them lie in the foreground. Credit: ESA/Webb, NASA & CSA, V. Almendros-Abad, M. Guarcello, K. Monsch, and the EWOCS team.



The final ESA/Webb Picture of the Month feature for 2025 showcases a festive-looking region filled with glowing clouds of gas and thousands of sparkling stars. This star cluster, known as Westerlund 2, resides in a stellar breeding ground known as Gum 29, located 20,000 light-years away from Earth in the constellation Carina (the Keel).

This image of Westerlund 2 uses data from Webb’s Near-InfraRed Camera (NIRCam) and Mid-InfraRed Instrument (MIRI). The cluster measures between 6 light-years and 13 light-years across, and is host to some of our Milky Way galaxy's hottest, brightest, and most massive stars. It was also the feature of Hubble’s 25th anniversary image in 2015.

;: This new Webb image captures the bright, brilliant cluster near the top that is packed with young, massive stars whose intense light shapes the entire scene. Below and around them, swirls of orange and red gas form sculpted walls and tangled clouds - material that is being pushed, eroded, and illuminated by the cluster’s powerful radiation. Threaded throughout the view are countless tiny stars just beginning to shine, some still surrounded by the gas and dust from which they formed. The soft blues and pinks are wisps of thinner material drifting between the denser clouds. Scattered across the field are also many bright stars much closer to us, whose sharp, star-shaped patterns are created by Webb’s optics. The result is a vivid portrait of a stellar nursery in action, where intense energy from newborn stars carves dramatic shapes into the surrounding nebula and drives the ongoing cycle of star formation.

These new Webb observations of Westerlund 2 have revealed, for the first time, the full population of brown dwarfs in this extremely massive young star cluster, including objects as small as about 10 times the mass of Jupiter. This data is allowing astronomers to find several hundred stars with discs in various evolutionary states to facilitate our understanding of how discs evolve and how planets form in such massive young clusters. This image was developed using data from Webb’s programme #3523 (M. Guarcello) as part of the Extended Westerlund 1 and 2 Open Clusters Survey (EWOCS).




Links


Monday, July 19, 2021

First Clear View of a Boiling Cauldron Where Stars are Born


The RCW 49 galactic nebula pictured above is one of the brightest star-forming regions in the Milky Way. By analyzing the movement of carbon atoms in an expanding bubble of gas surrounding the Westerlund 2 star cluster within RCW 49, a UMD-led team of researchers have created the clearest image to date of a stellar-wind driven bubble where stars are born. Image Credit: NASA/JPL-Caltec/E.Churchwell (University of Wisconsin).



A team led by UMD Astronomers created the first clear image of an expanding bubble of stellar gas where stars are born using data from NASA’s SOFIA telescope on board a heavily modified 747 jet. Artist Rendering by Marc Pound/UMD.

UMD-led team used NASA’s SOFIA telescope to capture high-resolution details of a star nursery in the Milky Way

University of Maryland researchers created the first high-resolution image of an expanding bubble of hot plasma and ionized gas where stars are born. Previous low-resolution images did not clearly show the bubble or reveal how it expanded into the surrounding gas.

The researchers used data collected by the Stratospheric Observatory for Infrared Astronomy (SOFIA) telescope to analyze one of the brightest, most massive star-forming regions in the Milky Way galaxy. Their analysis showed that a single, expanding bubble of warm gas surrounds the Westerlund 2 star cluster and disproved earlier studies suggesting there may be two bubbles surrounding Westerlund 2. The researchers also identified the source of the bubble and the energy driving its expansion. Their results were published in The Astrophysical Journal on June 23, 2021.

“When massive stars form, they blow off much stronger ejections of protons, electrons and atoms of heavy metal, compared to our sun,” said Maitraiyee Tiwari, a postdoctoral associate in the UMD Department of Astronomy and lead author of the study. “These ejections are called stellar winds, and extreme stellar winds are capable of blowing and shaping bubbles in the surrounding clouds of cold, dense gas. We observed just such a bubble centered around the brightest cluster of stars in this region of the galaxy, and we were able to measure its radius, mass and the speed at which it is expanding.”

The surfaces of these expanding bubbles are made of a dense gas of ionized carbon, and they form a kind of outer shell around the bubbles. New stars are believed to form within these shells. But like soup in a boiling cauldron, the bubbles enclosing these star clusters overlap and intermingle with clouds of surrounding gas, making it hard to distinguish the surfaces of individual bubbles.

Tiwari and her colleagues created a clearer picture of the bubble surrounding Westerlund 2 by measuring the radiation emitted from the cluster across the entire electromagnetic spectrum, from high-energy X-rays to low-energy radio waves. Previous studies, which only radio and submillimeter wavelength data, had produced low-resolution images and did not show the bubble. Among the most important measurements was a far-infrared wavelength emitted by a specific ion of carbon in the shell.

“We can use spectroscopy to actually tell how fast this carbon is moving either towards or away from us,” said Ramsey Karim (M.S. ’19, astronomy), a Ph.D. student in astronomy at UMD and a co-author of the study. “This technique uses the Doppler effect, the same effect that causes a train's horn to change pitch as it passes you. In our case, the color changes slightly depending on the velocity of the carbon ions.”

By determining whether the carbon ions were moving toward or away from Earth and combining that information with measurements from the rest of the electromagnetic spectrum, Tiwari and Karim were able to create a 3D view of the expanding stellar-wind bubble surrounding Westerlund 2.

In addition to finding a single, stellar wind-driven bubble around Westerlund 2, they found evidence of new stars forming in the shell region of this bubble. Their analysis also suggests that as the bubble expanded, it broke open on one side, releasing hot plasma and slowing expansion of the shell roughly a million years ago. But then, about 200,000 or 300,000 years ago, another bright star in Westerlund 2 evolved, and its energy re-invigorated the expansion of the Westerlund 2 shell.

“We saw that the expansion of the bubble surrounding Westerlund 2 was reaccelerated by  winds from another very massive star, and that started the process of expansion and star formation all over again,” Tiwari said. “This suggests stars will continue to be born in this shell for a long time, but as this process goes on, the new stars will become less and less massive.”

Tiwari and her colleagues will now apply their method to other bright star clusters and warm gas bubbles to better understand these star-forming regions of the galaxy. The work is part of a multi-year NASA-supported program called FEEDBACK

* * *

Additional co-authors of the research paper from UMD’s Department of Astronomy include Research Scientists Marc Pound and Mark Wolfire and Adjunct Professor Alexander Tielens.

This work was supported by the NASA-funded FEEDBACK project (Award No. SOF070077). The content of this article does not necessarily reflect the views of this organization.

The research paper"SOFIA FEEDBACK Survey: Exploring the Dynamics of the Stellar-wind-driven Shell of RCW 49" by Tiwari, M., Karim, R., Pound, M. W., Wolfire, M., Jacob, A., Buchbender, C., Güsten, R., Guevara, C., Higgins, R. D., Kabanovic, S., Pabst, C., Ricken, O., Schneider, N., Simon, R., Stutzki, J., Tielens, A. G. G. M., was published on June 23, 2021, in The Astrophysical Journal.

Media Relations Contact: 

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Saturday, May 30, 2020

Hubble Finds that "Distance" From the Brightest Stars is Key to Preserving Primordial Discs

The star cluster Westerlund 2
Westerlund 2 — Hubble’s 25th anniversary image

Wide-field image of Westerlund 2 (ground-based image)



Videos

Pan across Westerlund 2
Pan across Westerlund 2

Flight through star cluster Westerlund 2 - slow
Flight through star cluster Westerlund 2 - slow


The NASA/ESA Hubble Space Telescope was used to conduct a three-year study of the crowded, massive and young star cluster Westerlund 2. The research found that the material encircling stars near the cluster’s centre is mysteriously devoid of the large, dense clouds of dust that would be expected to become planets in a few million years. Their absence is caused by the cluster’s most massive and brightest stars that erode and disperse the discs of gas and dust of neighbouring stars. This is the first time that astronomers have analysed an extremely dense star cluster to study which environments are favourable to planet formation.

This time-domain study from 2016 to 2019 sought to investigate the properties of stars during their early evolutionary phases and to trace the evolution of their circumstellar environments [1]. Such studies had previously been confined to the nearest, low-density, star-forming regions. Astronomers have now used the Hubble Space Telescope to extend this research to the centre of one of the few young massive clusters in the Milky Way, Westerlund 2, for the first time.

Astronomers have now found that planets have a tough time forming in this central region of the cluster. The observations also reveal that stars on the cluster’s periphery do have immense planet-forming dust clouds embedded in their discs. To explain why some stars in Westerlund 2 have a difficult time forming planets while others do not, researchers suggest this is largely due to location. The most massive and brightest stars in the cluster congregate in the core. Westerlund 2 contains at least 37 extremely massive stars, some weighing up to 100 solar masses. Their blistering ultraviolet radiation and hurricane-like stellar winds act like blowtorches and erode the discs around neighbouring stars, dispersing the giant dust clouds.

“Basically, if you have monster stars, their energy is going to alter the properties of the discs,” explained lead researcher Elena Sabbi, of the Space Telescope Science Institute in Baltimore, USA. “You may still have a disc, but the stars change the composition of the dust in the discs, so it’s harder to create stable structures that will eventually lead to planets. We think the dust either evaporates away in 1 million years, or it changes in composition and size so dramatically that planets don’t have the building blocks to form.”

Westerlund 2 is a unique laboratory in which to study stellar evolutionary processes because it’s relatively nearby, is quite young, and contains a rich stellar population. The cluster resides in a stellar breeding ground known as Gum 29, located roughly 14 000 light-years away in the constellation of Carina (The Ship’s Keel). The stellar nursery is difficult to observe because it is surrounded by dust, but Hubble’s Wide Field Camera 3 can peer through the dusty veil in near-infrared light, giving astronomers a clear view of the cluster. Hubble’s sharp vision was used to resolve and study the dense concentration of stars in the central cluster.

“With an age of less than about two million years, Westerlund 2 harbours some of the most massive, and hottest, young stars in the Milky Way,” said team member Danny Lennon of the Instituto de Astrofísica de Canarias and the Universidad de La Laguna. “The ambient environment of this cluster is therefore constantly bombarded by strong stellar winds and ultraviolet radiation from these giants that have masses of up to 100 times that of the Sun.”

Sabbi and her team found that of the nearly 5000 stars in Westerlund 2 with masses between 0.1 and 5 times the Sun’s mass, 1500 of them show dramatic fluctuations in their luminosity, which is commonly accepted as being due to the presence of large dusty structures and planetesimals. Orbiting material would temporarily block some of the starlight, causing fluctuations in brightness. However, Hubble only detected the signature of dust particles around stars outside the central region. They did not detect these dips in brightness in stars residing within four light-years of the centre. 

“We think they are planetesimals or structures in formation,” Sabbi explained. “These could be the seeds that eventually lead to planets in more evolved systems. These are the systems we don’t see close to very  massive stars. We see them only in systems outside the centre.”

Thanks to Hubble, astronomers can now see how stars are accreting in environments that are like the early Universe, where clusters were dominated by monster stars. So far, the best known nearby stellar environment that contains massive stars is the starbirth region in the Orion Nebula. However, Westerlund 2 is a richer target because of its larger stellar population. 

“Westerlund 2 gives us much better statistics on how mass affects the evolution of  stars, how rapidly they evolve, and we see the evolution of stellar discs and the importance of stellar feedback in modifying the properties of these systems,” said Sabbi. “We can use all of this information to inform models of planet formation and stellar evolution.”

This cluster will also be an excellent target for follow-up observations with the upcoming NASA/ESA/CSA James Webb Space Telescope, an infrared observatory. Hubble has helped astronomers identify the stars that have possible planetary structures. With the Webb telescope, researchers will be able to study which discs around stars are not accreting material and which discs still have material that could build up into planets. Webb will also study the chemistry of the discs in different evolutionary phases and watch how they change, to help astronomers determine what role the environment plays in their evolution.

“A major conclusion of this work is that the powerful ultraviolet radiation of massive stars alters the discs around neighbouring stars,” said Lennon. “If this is confirmed with measurements by the James Webb Space Telescope, this result may also explain why planetary systems are rare in old massive globular clusters.”



Notes

[1] These observations were made under Hubble observing programs #14087, #15362, and #15514.



More Information

The Hubble Space Telescope is a project of international cooperation between ESA and NASA.

The international team of astronomers in this study consists of E. Sabbi, M. Gennaro, J. Anderson, V. Bajaj, N. Bastian, J. S. Gallagher, III, M. Gieles, D. J. Lennon, A. Nota, K. C. Sahu, and P. Zeidler.

Image credit: NASA, ESA, the Hubble Heritage Team (STScI/AURA), A. Nota (ESA/STScI), and the Westerlund 2 Science Team




Links

Elena Sabbi
Space Telescope Science Institute
Baltimore, MD, USA
Email:
sabbi@stsci.edu

Bethany Downer
ESA/Hubble, Public Information Officer
Garching, Germany
Email:
Bethany.Downer@partner.eso.org



Monday, October 17, 2016

Discovering the Treasures in Chandra’s Archives

Each year, NASA’s Chandra X-ray Observatory helps celebrate American Archive Month by releasing a collection of images using X-ray data in its archive.

The Chandra Data Archive is a sophisticated digital system that ultimately contains all of the data obtained by the telescope since its launch into space in 1999. Chandra’s archive is a resource that makes these data available to the scientific community and the general public for years after they were originally obtained.

Each of these six new images also includes data from telescopes covering other parts of the electromagnetic spectrum, such as visible and infrared light. This collection of images represents just a small fraction of the treasures that reside in Chandra’s unique X-ray archive.
From left to right, starting on the top row, the objects are:

 Westerlund 2, 3C31, PSR J1509-5850, Abell 665, RX J0603.3+4214 and CTB 37A


Westerlund 2: A cluster of young stars – about one to two million years old – located about 20,000 light years from Earth.  Data in visible light from the Hubble Space Telescope (green and blue) reveal thick clouds where the stars are forming. High-energy radiation in the form of X-rays, however, can penetrate this cosmic haze, and are detected by Chandra (purple).

3C31: X-rays from the radio galaxy 3C31 (blue), located 240 million light years from Earth, allow astronomers to probe the density, temperature, and pressure of this galaxy, long known to be a powerful emitter of radio waves. The Chandra data also reveal a jet blasting away from one side of the central galaxy, which also is known as NGC 383.  Here, the Chandra X-ray image has been combined with Hubble’s visible light data (yellow).

PSR J1509-5850: Pulsars were first discovered in 1967 and today astronomers know of over a thousand such objects. The pulsar, PSR J1509-5850, located about 12,000 light years from Earth and appearing as the bright white spot in the center of this image, has generated a long tail of X-ray emission trailing behind it, as seen in the lower part of the image. This pulsar has also generated an outflow of particles in approximately the opposite direction. In this image, X-rays detected by Chandra (blue) and radio emission (pink) have been overlaid on a visible light image from the Digitized Sky Survey of the field of view.

Abell 665: Merging galaxy clusters can generate enormous shock waves, similar to cold fronts in weather on Earth. This system, known as Abell 665, has an extremely powerful shockwave, second only to the famous Bullet Cluster. Here, X-rays from Chandra (blue) show hot gas in the cluster. The bow wave shape of the shock is shown by the large white region near the center of the image. The Chandra image has been added to radio emission (purple) and visible light data from the Sloan Digital Sky Survey showing galaxies and stars (white).

RX J0603.3+4214: The phenomenon of pareidolia is when people see familiar shapes in images. This galaxy cluster has invoked the nickname of the “Toothbrush Cluster” because of its resemblance to the dental tool. In fact, the stem of the brush is due to radio waves (green) while the diffuse emission where the toothpaste would go is produced by X-rays observed by Chandra (purple). Visible light data from the Subaru telescope show galaxies and stars (white) and a map from gravitational lensing (blue) shows the concentration of the mass, which is mostly (about 80%) dark matter.

CTB 37A: Astronomers estimate that a supernova explosion should occur about every 50 years on average in the Milky Way galaxy. The object known as CTB 37A is a supernova remnant located in our Galaxy about 20,000 light years from Earth. This image shows that the debris field glowing in X-rays (blue) and radio waves (pink) may be expanding into a cooler cloud of gas and dust seen in infrared light (orange).

NASA's Marshall Space Flight Center in Huntsville, Alabama, manages the Chandra program for NASA's Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory in Cambridge, Massachusetts, controls Chandra's science and flight operations. 


Read More from NASA's Chandra X-ray Observatory.


For more Chandra images, multimedia and related materials, visit: http://www.nasa.gov/chandra


Molly Porter
Marshall Space Flight Center, Huntsville, Ala.
256-544-0034

molly.a.porter@nasa.gov

Megan Watzke
Chandra X-ray Center, Cambridge, Mass.
617-496-7998

mwatzke@cfa.harvard.edu

Editor: Lee Mohon

Friday, April 24, 2015

Celestial fireworks celebrate Hubble’s 25th anniversary

Westerlund 2 — Hubble’s 25th anniversary image

Wide-field image of Westerlund 2 (ground-based image)

The star cluster Westerlund 2

Star-forming region Gum 29

Pillars around Westerlund 2

New stars around Westerlund 2 

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VIDEOS

Hubblecast Episode 84: A starry snapshot for Hubble’s 25th
Hubblecast Episode 84: A starry snapshot for Hubble’s 25th

Zoom into Westerlund 2
Zoom into Westerlund 2

Westerlund 2 for fulldome
Westerlund 2 for fulldome

Pan across Westerlund 2
Pan across Westerlund 2

Flight through star cluster Westerlund 2 — fast
Flight through star cluster Westerlund 2 — fast

Flight through star cluster Westerlund 2 - slow
Flight through star cluster Westerlund 2 - slow


The glittering tapestry of young stars flaring to life in this new NASA/ESA Hubble Space Telescope image aptly resembles an exploding shell in a fireworks display. This vibrant image of the star cluster Westerlund 2 has been released to celebrate Hubble’s 25th year in orbit and a quarter of a century of new discoveries, stunning images and outstanding science.

On 24 April 1990 the NASA/ESA Hubble Space Telescope was sent into orbit aboard the space shuttle Discovery as the first space telescope of its kind. It offered a new view of the Universe and has, for 25 years, reached and surpassed all expectations, beaming back data and images that have changed scientists’ understanding of the Universe and the public’s perception of it.

In this image, the sparkling centrepiece of Hubble’s silver anniversary fireworks is a giant cluster of about 3000 stars called Westerlund 2 [1][2]. The cluster resides in a raucous stellar breeding ground known as Gum 29, located 20 000 light-years away in the constellation Carina.

The stellar nursery is difficult to observe because it is surrounded by dust, but Hubble’s Wide Field Camera 3 peered through the dusty veil in near-infrared light, giving astronomers a clear view of the cluster. Hubble’s sharp vision resolves the dense concentration of stars in the central cluster, which measures only about 10 light-years across.

The giant star cluster is only about two million years old, but contains some of the brightest, hottest and most massive stars ever discovered. Some of the heftiest stars are carving deep cavities in the surrounding material by unleashing torrents of ultraviolet light and high speed streams of charged particles, known as stellar winds. These are etching away the enveloping hydrogen gas cloud in which the stars were born and are responsible for the weird and wonderful shapes of the clouds of gas and dust in the image.

The pillars in the image are composed of dense gas and dust, and are resisting erosion from the fierce radiation and powerful winds. These gaseous monoliths are a few light-years tall and point to the central cluster. Other dense regions surround the pillars, including dark filaments of dust and gas.

Besides sculpting the gaseous terrain, the brilliant stars can also help create a succeeding generation of offspring. When the stellar winds hit dense walls of gas, they create shocks, which generate a new wave of star birth along the wall of the cavity. The red dots scattered throughout the landscape are a rich population of forming stars that are still wrapped in their gas and dust cocoons. These stellar foetuses have not yet ignited the hydrogen in their cores to light-up as stars. However, Hubble’s near-infrared vision allows astronomers to identify these fledglings. The brilliant blue stars seen throughout the image are mostly in the foreground.

The image’s central region, containing the star cluster, blends visible-light data taken by the Advanced Camera for Surveys and near-infrared exposures taken by the Wide Field Camera 3. The surrounding region is composed of visible-light observations taken by the Advanced Camera for Surveys.

This image is a testament to Hubble’s observational power and demonstrates that, even with 25 years of operations under its belt, Hubble’s story is by no means over. Hubble has set the stage for its companion the James Webb Space Telescope — scheduled for launch in 2018 — but will not be immediately replaced by this new feat of engineering, instead working alongside it. Now, 25 years after launch, is the time to celebrate Hubble’s future potential as well as its remarkable history.


Notes

[1] A new anniversary image is released every year; last year Hubble snapped the ethereal Monkey Head Nebula (heic1406). The year 2013 saw the release of a strikingly delicate view of the Horsehead Nebula (heic1307), and Hubble’s 22nd year was marked by a huge mosaic of a celestial spider (heic1206)! Other images include a multicoloured view of Saturn (opo9818a), a Tolkien-esque shot of the Carina Nebula (heic1007a), and a beautiful cosmic rose made up of merging galaxies (heic1107a). More anniversary images can be seen here.

[2] Westerlund 2 is named after Swedish astronomer Bengt Westerlund, who discovered the grouping in the 1960s.


Notes for Editors

The Hubble Space Telescope is a project of international cooperation between ESA and NASA.


More Information

Image credit: NASA, ESA, the Hubble Heritage Team (STScI/AURA), A. Nota (ESA/STScI), and the Westerlund 2 Science Team

The original observations of Westerlund 2 were obtained by the science team: Antonella Nota (ESA/STScI), Elena Sabbi (STScI), Eva Grebel and Peter Zeidler (Astronomisches Rechen-Institut Heidelberg), Monica Tosi (INAF, Osservatorio Astronomico di Bologna), Alceste Bonanos (National Observatory of Athens, Astronomical Institute), Carol Christian (STScI/AURA) and Selma de Mink (University of Amsterdam). Follow-up observations were made by the Hubble Heritage team: Zoltan Levay (STScI), Max Mutchler, Jennifer Mack, Lisa Frattare, Shelly Meyett, Mario Livio, Carol Christian (STScI/AURA), and Keith Noll (NASA/GSFC).


Links

Contacts

Georgia Bladon
ESA/Hubble, Public Information Officer
Garching, Germany
Cell: +44 7816291261
Email:
gbladon@partner.eso.org

Ray Villard
Space Telescope Science Institute
Baltimore, USA
Tel: +1-410-338-4514
Email:
villard@stsci.edu