The Eagle Nebula (M16): Peering Into the Pillars Of Creation
A new look at the famous "Pillars of Creation" with NASA's Chandra X-ray Observatory has allowed astronomers to peer inside the dark columns of gas and dust. This penetrating view of the central region of the Eagle Nebula reveals how much star formation is happening inside these iconic structures.
The Chandra data shows bright X-ray so
A new look at the famous "Pillars of Creation" with NASA's Chandra X-ray Observatory has allowed astronomers to peer inside the dark columns of gas and dust. This penetrating view of the central region of the Eagle Nebula reveals how much star formation is happening inside these iconic structures.
The Chandra data shows bright X-ray so
urces in this field, most of which are young stars. In this image, red, green, and blue represent low, medium, and high energy X-rays. The Chandra data have been overlaid on the Hubble Space Telescope image to show the context of these X-ray data.
Very few X-ray sources are found in the pillars themselves. This suggests that the Eagle Nebula may be past its star-forming prime, since young stars are usually bright X-ray sources. However, there are two X-ray objects found near the tips of the pillars. One is a young star about 4 or 5 times as massive as the Sun, visible as the blue source near the tip of the pillar on the left. The other is a lower mass star near the top of the other pillar that is so faint it is not visible in the composite image.
The Chandra observations did not detect X-rays from any of the so-called evaporating gaseous globules, or EGGs. The EGGs are dense, compact pockets of interstellar gas where stars are believed to be forming. The lack of X-rays from these objects may mean that most of the EGGs do not contain enshrouded stars. However, infrared observations have shown that 11 of the 73 EGGs contain infant stellar objects and 4 of these are massive enough to form a star. The stars embedded in these 4 EGGs might be so young that they have not generated X-rays yet and one of them (E42) - estimated to have about the mass of the Sun - could represent one of the earliest stages of evolution of our nearest star. The Sun was likely born in a region like the Pillars of Creation.
The pillars and the few stars forming inside them are the last vestiges of star formation in the Eagle Nebula, also known as M16, which peaked several million years earlier. This contrasts strongly with the active star forming regions in other clusters such as NGC 2024, where Chandra sees a dense cluster of embedded young stars.
The results were published in the January 1st issue of The Astrophysical Journal and the research team, led by Jeffrey Linsky of the University of Colorado, includes Marc Gagne and Anna Mytyk (West Chester University), Mark McCaughrean (University of Exeter) and Morten Andersen (University of Arizona).
Fast Facts for The Eagle Nebula (M16):
Credit X-ray: NASA/CXC/U.Colorado/
Scale: Image is 2.5 arcmin across
Category Normal Stars & Star Clusters
Coordinates (J2000) RA 18h 18m 51.79s | Dec -13º 49' 54.93"
Constellation Serpens
Observation Date 30 Jul 01
Observation Time 22 hours
Obs. ID 978
Color Code X-ray: Red(0.5-1.5 keV); Green(1.5-2.5 keV); Blue(2.5-7.0 keV)
Instrument ACIS
References Linsky et al. (2007), ApJ, 654, 347
Distance Estimate About 7,000 light years
Release Date February 15, 2007
Very few X-ray sources are found in the pillars themselves. This suggests that the Eagle Nebula may be past its star-forming prime, since young stars are usually bright X-ray sources. However, there are two X-ray objects found near the tips of the pillars. One is a young star about 4 or 5 times as massive as the Sun, visible as the blue source near the tip of the pillar on the left. The other is a lower mass star near the top of the other pillar that is so faint it is not visible in the composite image.
The Chandra observations did not detect X-rays from any of the so-called evaporating gaseous globules, or EGGs. The EGGs are dense, compact pockets of interstellar gas where stars are believed to be forming. The lack of X-rays from these objects may mean that most of the EGGs do not contain enshrouded stars. However, infrared observations have shown that 11 of the 73 EGGs contain infant stellar objects and 4 of these are massive enough to form a star. The stars embedded in these 4 EGGs might be so young that they have not generated X-rays yet and one of them (E42) - estimated to have about the mass of the Sun - could represent one of the earliest stages of evolution of our nearest star. The Sun was likely born in a region like the Pillars of Creation.
The pillars and the few stars forming inside them are the last vestiges of star formation in the Eagle Nebula, also known as M16, which peaked several million years earlier. This contrasts strongly with the active star forming regions in other clusters such as NGC 2024, where Chandra sees a dense cluster of embedded young stars.
The results were published in the January 1st issue of The Astrophysical Journal and the research team, led by Jeffrey Linsky of the University of Colorado, includes Marc Gagne and Anna Mytyk (West Chester University), Mark McCaughrean (University of Exeter) and Morten Andersen (University of Arizona).
Fast Facts for The Eagle Nebula (M16):
Credit X-ray: NASA/CXC/U.Colorado/
Scale: Image is 2.5 arcmin across
Category Normal Stars & Star Clusters
Coordinates (J2000) RA 18h 18m 51.79s | Dec -13º 49' 54.93"
Constellation Serpens
Observation Date 30 Jul 01
Observation Time 22 hours
Obs. ID 978
Color Code X-ray: Red(0.5-1.5 keV); Green(1.5-2.5 keV); Blue(2.5-7.0 keV)
Instrument ACIS
References Linsky et al. (2007), ApJ, 654, 347
Distance Estimate About 7,000 light years
Release Date February 15, 2007
Cygnus OB2: Probing a Nearby Stellar Cradle
Cygnus OB2 is a star cluster in the Milky Way that contains many hot, massive young stars.
This composite image of Cygnus OB2 contains X-rays from Chandra (blue), infrared data from Spitzer (red), and optical data from the Isaac Newton Telescope (orange).
Astronomers would like to better understand how this and other star factories like it form and evolve.
A deep Chandra observation of Cygnus OB2 has found almost 1,500 stars emitting X-rays.
The Milky Way and other galaxies in the universe harbor many young star clusters and associations that each contain hundreds to thousands of hot, massive, young stars known as O and B stars. The star cluster Cygnus OB2 contains more than 60 O-type stars and about a thousand B-type stars. At a relatively nearby distance to Earth of about 5,000 light years, Cygnus OB2 is the closest massive cluster. Deep observations with NASA's Chandra X-ray Observatory of Cygnus OB2 have been used to detect the X-ray emission from the hot outer atmospheres, or coronas, of young stars in the cluster and to probe how these great star factories form and evolve. About 1,700 X-ray sources were detected, including about 1,450 thought to be stars in the cluster. In this image, X-rays from Chandra (blue) have been combined with infrared data from NASA's Spitzer Space Telescope (red) and optical data from the Isaac Newton Telescope (orange).
Young stars ranging in age from one million to seven million years were detected. The infrared data indicates that a very low fraction of the stars have circumstellar disks of dust and gas. Even fewer disks were found close to the massive OB stars, betraying the corrosive power of their intense radiation that leads to early destruction of their disks. Evidence is also seen that the older population of stars has lost its most massive members because of supernova explosions. Finally, a total mass of about 30,000 times the mass of the sun is derived for Cygnus OB2, similar to that of the most massive star forming regions in our Galaxy.
Fast Facts for Cygnus OB2:
Credit X-ray: NASA/CXC/SAO/J.Drake et al, Optical: Univ. of Hertfordshire/INT/IPHAS, Infrared: NASA/JPL-Caltech
Release Date : November 7, 2012
Scale Image is 11.8 arcmin across (16 light years)
Category: Normal Stars & Star Clusters
Coordinates (J2000) RA 20h 37m 11.00s | Dec +38° 41' 52.00"
Constellation: Cygnus
Observation Date: 39 pointings between January 2004 and March 2010
Observation Tim : 341 hours 40 min (14 days 5 hours 40 min)
Obs. ID 4501, 4511, 10939-10974, 12099
Instrument: ACIS
Color Code X-ray (Blue), Optical (Yellow), Infrared (Red)
Distance Estimate: About 4,700 light year
Cygnus OB2 is a star cluster in the Milky Way that contains many hot, massive young stars.
This composite image of Cygnus OB2 contains X-rays from Chandra (blue), infrared data from Spitzer (red), and optical data from the Isaac Newton Telescope (orange).
Astronomers would like to better understand how this and other star factories like it form and evolve.
A deep Chandra observation of Cygnus OB2 has found almost 1,500 stars emitting X-rays.
The Milky Way and other galaxies in the universe harbor many young star clusters and associations that each contain hundreds to thousands of hot, massive, young stars known as O and B stars. The star cluster Cygnus OB2 contains more than 60 O-type stars and about a thousand B-type stars. At a relatively nearby distance to Earth of about 5,000 light years, Cygnus OB2 is the closest massive cluster. Deep observations with NASA's Chandra X-ray Observatory of Cygnus OB2 have been used to detect the X-ray emission from the hot outer atmospheres, or coronas, of young stars in the cluster and to probe how these great star factories form and evolve. About 1,700 X-ray sources were detected, including about 1,450 thought to be stars in the cluster. In this image, X-rays from Chandra (blue) have been combined with infrared data from NASA's Spitzer Space Telescope (red) and optical data from the Isaac Newton Telescope (orange).
Young stars ranging in age from one million to seven million years were detected. The infrared data indicates that a very low fraction of the stars have circumstellar disks of dust and gas. Even fewer disks were found close to the massive OB stars, betraying the corrosive power of their intense radiation that leads to early destruction of their disks. Evidence is also seen that the older population of stars has lost its most massive members because of supernova explosions. Finally, a total mass of about 30,000 times the mass of the sun is derived for Cygnus OB2, similar to that of the most massive star forming regions in our Galaxy.
Fast Facts for Cygnus OB2:
Credit X-ray: NASA/CXC/SAO/J.Drake et al, Optical: Univ. of Hertfordshire/INT/IPHAS, Infrared: NASA/JPL-Caltech
Release Date : November 7, 2012
Scale Image is 11.8 arcmin across (16 light years)
Category: Normal Stars & Star Clusters
Coordinates (J2000) RA 20h 37m 11.00s | Dec +38° 41' 52.00"
Constellation: Cygnus
Observation Date: 39 pointings between January 2004 and March 2010
Observation Tim : 341 hours 40 min (14 days 5 hours 40 min)
Obs. ID 4501, 4511, 10939-10974, 12099
Instrument: ACIS
Color Code X-ray (Blue), Optical (Yellow), Infrared (Red)
Distance Estimate: About 4,700 light year
Stellar Evolution with Type 1a Supernova Remnant
This tableau illustrates the ongoing drama of stellar evolution, and how the rate of evolution and the ultimate fate of a star depends on its weight, or mass. (Illustration:
This graphic gives a summary of our best current understanding of the evolution of stars, showing their birth, middle age and eventual demise. The lowest mass stars are shown
This tableau illustrates the ongoing drama of stellar evolution, and how the rate of evolution and the ultimate fate of a star depends on its weight, or mass. (Illustration:
This graphic gives a summary of our best current understanding of the evolution of stars, showing their birth, middle age and eventual demise. The lowest mass stars are shown
at the bottom and the highest mass stars at the top. The very top line is a relatively recent addition compelled by the detection of SN 2006gy, that describes the evolution of the most massive stars in the universe. Observational evidence for the special type of explosion shown here - which is incredibly bright and obliterates the star rather than producing a black hole - was lacking until SN 2006gy was found.
Pelican Nebula Close-up
The prominent ridge of emission featured in this vivid skyscape is designated IC 5067. Part of a larger emission nebula with a distinctive shape, popularly called The Pelican Nebula, the ridge spans about 10 light-years and follows the curve of the cosmic pelican's head and neck. Fantastic, dark shapes inhabiting the view are clouds of cool gas and dust sculpted by energe
tic radiation from hot, massive stars. But stars are also forming within the dark shapes. In fact, twin jets emerging from the tip of the central, dark tendril are the telltale signs of an embedded protostar cataloged as Herbig-Haro 555. The Pelican Nebula itself, also known as IC 5070, is about 2,000 light-years away. To find it, look northeast of bright star Deneb in the high flying constellation Cygnus.
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