230627 - M16 "Eagle" nebula
|
click image to enlarge
|
ASTRO:
type=Emission nebula mag=6.0 const=Serpens dist=5700 ly size=116 ly IMAGE: location=EB Driveway BrtlCls=4 moon=50% WxQtr exposure=CMOS OSC; 77x300s (6.4h), Gain125 (avg.) drizzle=2x palette=HOO EQUIPMENT: camera=ZWO ASI2600MC-Pro optics=ES102 w1.0x fltnr, F=714mm, f/7.0 filter=Radian Triad Ultra Quad NB mount=Celestron AVX guiding=Orion 60x240mm scope, ZWO ASi224MC camera SOFTWARE: acquisition=Stellarium, APT, PHD2, processing=PixInsight, <RCAstro>, <SetiAstro>, PhotoshopCC, <APF-R>, <Lumenzia>, LrC |
|
The Eagle Nebula, catalogued as Messier 16 (or M16) is a cloud of gas and dust inside our home galaxy, the Milky Way. It contains a very visible young open cluster of stars (NGC 6611) in the constellation Serpens, discovered by Jean-Philippe de Cheseaux in 1746. The "Eagle" refers to visual impressions of the bright silhouette near the center of the nebula, an area made famous for its "Pillars of Creation" imaged by the Hubble Space Telescope ("HST") in 1995. The nebula lies in the Sagittarius Arm of the Milky Way.
The NGC 6611 star cluster associated with the nebula contains appx 8100 stars, which are mostly concentrated in a gap of the associated molecular cloud to the north of the 'Pillars'. The brightest star (HD 168076) has an apparent magnitude of +8.24, easily visible with good binoculars; and, it is a binary star. This binary has a mass roughly 80 x that of our Sun, and a luminosity appx 1 million times that of our Sun. The cluster's age has been estimated to be very young (by astronomical standards) at 1.5 M years old, which is appx 7.5 x older than the Jurassic period of the dinosaurs here on Earth.
THE EAGLE NEBULA: HOLDS A STORY OF TRIUMPH OVER ADVERSITY...
When the HST was placed in orbit in April 1990, its first images retrieved by NASA were blurry and unusable for astronomical research. They were considered totally unacceptable for the purpose which the HST had been built. NASA determined, and then announced publicly that Hubble’s 7'10" primary mirror had an imperfection called 'spherical aberration', which affected the clarity of the telescope’s images. The curvature of the mirror was off by 2 microns, or about 1/50th the width of a human hair, making its images blurry. When the finger pointing began, it was quickly determined that a contractor who had ground the mirror into shape, had not ground enough of a curvature, leaving it too flat. It turns-out that because of receiving tremendous pressure from NASA Management to meet the launch schedule, that contractor ran out of time to complete test measurements, and had failed to find the error and correct it prior to launch. It was a $95M mistake (...roughly $195M in 2025 dollars). As NASA’s competency began to be called into question, NASA Director of Astrophysics, Charlie Pellerin stepped-up and took full responsibility.
After being publicly assailed for failing their primary mission, NASA project scientists, engineers and contractors rallied, literally picking themselves up from the floor by their bootstraps, and got busy developing a corrective plan for the failed telescope. One aspect that had originally helped justify the HST project was its coincidental development alongside the NASA Space Shuttle Program. While the 2 programs were not initially envisioned to intersect until much later, and only then for maintenance purposes, the timing of this HST “issue” turned-out to be very-well aligned with the current capabilities of the Space Shuttle initiative. It took 3½ years to plan and implement the ensuing "rescue" mission; all the while HST remained in orbit – utterly useless.
Then in December 1993, the crew of Space Shuttle Endeavor successfully docked with the HST in outer space. While anchored to the end of the Shuttle’s onboard mechanical arm, Astronauts Jeffrey Hoffman and Story Musgrave worked fearlessly on the HST from outside the shuttle payload compartment. While not the first "spacewalk" performed by NASA astronauts, this was the first time such an intricate and complex procedure had been performed in the open expanse of space. HST's faulty primary mirror had been ground very precisely, just to the wrong shape. This led to the design of new optical components with exactly the same error but in the opposite, off-setting sense. Ultimately, Hoffman & Musgrave were successful replacing the existing HST camera with a new one that was fitted with "glasses" to improve the telescope’s vision when paired with the faulty mirror.
Then in April 1995, an image produced by Professors Jeff Hester and Paul Scowen of the Arizona State University School of Astronomy, using exposures gathered from the HST, demonstrated just how greatly improved the "New Hubble" really was. They released their now famous image of the "Pillars of Creation", which are located in the heart of the Eagle Nebula, and depicting the large, iconic columnar regions of star formation.
Now, drawing the opposite of the dread and shame of 5 years earlier, the image brought widespread international acclaim to Hester & Scowen, to the Hubble Space Telescope, and to the NASA Space Shuttle program. It is a remarkable story of triumph over adversity. The image is noted for its global cultural impact. National Geographic Magazine cited in its 20th anniversary edition that the image had been featured in thousands of news reports around the world and had captured the imagination of a large segment of the World's population. In addition to the news reports, the image was showcased in merchandising efforts including everything from "coffee-mugs to T-shirts". Not since Neil Armstrong walked on the Moon in July of 1969 had the American Space Program influenced the imaginations of so many, so dramatically.
These 'Pillars' – which resemble stalagmites protruding from the floor of a cavern – are composed of interstellar dust and hydrogen gas. They stand appx four (4) light-years tall. Calculating through the math, it would take more than 3600 of our solar systems stacked in a vertical row to span them. The columns act as incubators for new stars. Inside the columns and on their surfaces, scientists have found "knots", or globules of denser gas, and have affectionately named them, "EGG's" ("Evaporating Gaseous Globules") where stars are being formed and borne from within.
Today, almost three (3) decades after Hester & Cowan's monumental achievement, the James Webb Space Telescope (or JWST) has paid another visit to The Pillars and provided significant improvements to both images captured of the region, and our understanding of star formation. Here is NASA's newest image captured in October of 2022. This image results from using the Near Infrared (or NIR) camera of JWST, which is capable of seeing deeply into the internal structures of the columns. There, we are witnessing in amazing detail the actual birthing of new, young stars, and the fundamentals of God's creation actually taking place!!
In April each year and from North America, the Eagle first becomes visible in the early morning hours (just before sunrise), then progresses to full evening views beginning in June and continuing through August. It then retreats into the dusk of evening sunsets in October and finally disappears in November, not to return until the early mornings of the following April.
In the amateur image included here, the Pillars of Creation are clearly visible within the heart of the nebula. In addition to the above heroic story, they stand as a testament to recent technological advancements in astronomical science, both within the ranks of the professional astro-scientific community, but also among amateur astronomical enthusiasts. The Pillars represent a "pinnacle" in photographic excellence for many aspiring astrophotographers as they seek to develop their craft.
The NGC 6611 star cluster associated with the nebula contains appx 8100 stars, which are mostly concentrated in a gap of the associated molecular cloud to the north of the 'Pillars'. The brightest star (HD 168076) has an apparent magnitude of +8.24, easily visible with good binoculars; and, it is a binary star. This binary has a mass roughly 80 x that of our Sun, and a luminosity appx 1 million times that of our Sun. The cluster's age has been estimated to be very young (by astronomical standards) at 1.5 M years old, which is appx 7.5 x older than the Jurassic period of the dinosaurs here on Earth.
THE EAGLE NEBULA: HOLDS A STORY OF TRIUMPH OVER ADVERSITY...
When the HST was placed in orbit in April 1990, its first images retrieved by NASA were blurry and unusable for astronomical research. They were considered totally unacceptable for the purpose which the HST had been built. NASA determined, and then announced publicly that Hubble’s 7'10" primary mirror had an imperfection called 'spherical aberration', which affected the clarity of the telescope’s images. The curvature of the mirror was off by 2 microns, or about 1/50th the width of a human hair, making its images blurry. When the finger pointing began, it was quickly determined that a contractor who had ground the mirror into shape, had not ground enough of a curvature, leaving it too flat. It turns-out that because of receiving tremendous pressure from NASA Management to meet the launch schedule, that contractor ran out of time to complete test measurements, and had failed to find the error and correct it prior to launch. It was a $95M mistake (...roughly $195M in 2025 dollars). As NASA’s competency began to be called into question, NASA Director of Astrophysics, Charlie Pellerin stepped-up and took full responsibility.
After being publicly assailed for failing their primary mission, NASA project scientists, engineers and contractors rallied, literally picking themselves up from the floor by their bootstraps, and got busy developing a corrective plan for the failed telescope. One aspect that had originally helped justify the HST project was its coincidental development alongside the NASA Space Shuttle Program. While the 2 programs were not initially envisioned to intersect until much later, and only then for maintenance purposes, the timing of this HST “issue” turned-out to be very-well aligned with the current capabilities of the Space Shuttle initiative. It took 3½ years to plan and implement the ensuing "rescue" mission; all the while HST remained in orbit – utterly useless.
Then in December 1993, the crew of Space Shuttle Endeavor successfully docked with the HST in outer space. While anchored to the end of the Shuttle’s onboard mechanical arm, Astronauts Jeffrey Hoffman and Story Musgrave worked fearlessly on the HST from outside the shuttle payload compartment. While not the first "spacewalk" performed by NASA astronauts, this was the first time such an intricate and complex procedure had been performed in the open expanse of space. HST's faulty primary mirror had been ground very precisely, just to the wrong shape. This led to the design of new optical components with exactly the same error but in the opposite, off-setting sense. Ultimately, Hoffman & Musgrave were successful replacing the existing HST camera with a new one that was fitted with "glasses" to improve the telescope’s vision when paired with the faulty mirror.
Then in April 1995, an image produced by Professors Jeff Hester and Paul Scowen of the Arizona State University School of Astronomy, using exposures gathered from the HST, demonstrated just how greatly improved the "New Hubble" really was. They released their now famous image of the "Pillars of Creation", which are located in the heart of the Eagle Nebula, and depicting the large, iconic columnar regions of star formation.
Now, drawing the opposite of the dread and shame of 5 years earlier, the image brought widespread international acclaim to Hester & Scowen, to the Hubble Space Telescope, and to the NASA Space Shuttle program. It is a remarkable story of triumph over adversity. The image is noted for its global cultural impact. National Geographic Magazine cited in its 20th anniversary edition that the image had been featured in thousands of news reports around the world and had captured the imagination of a large segment of the World's population. In addition to the news reports, the image was showcased in merchandising efforts including everything from "coffee-mugs to T-shirts". Not since Neil Armstrong walked on the Moon in July of 1969 had the American Space Program influenced the imaginations of so many, so dramatically.
These 'Pillars' – which resemble stalagmites protruding from the floor of a cavern – are composed of interstellar dust and hydrogen gas. They stand appx four (4) light-years tall. Calculating through the math, it would take more than 3600 of our solar systems stacked in a vertical row to span them. The columns act as incubators for new stars. Inside the columns and on their surfaces, scientists have found "knots", or globules of denser gas, and have affectionately named them, "EGG's" ("Evaporating Gaseous Globules") where stars are being formed and borne from within.
Today, almost three (3) decades after Hester & Cowan's monumental achievement, the James Webb Space Telescope (or JWST) has paid another visit to The Pillars and provided significant improvements to both images captured of the region, and our understanding of star formation. Here is NASA's newest image captured in October of 2022. This image results from using the Near Infrared (or NIR) camera of JWST, which is capable of seeing deeply into the internal structures of the columns. There, we are witnessing in amazing detail the actual birthing of new, young stars, and the fundamentals of God's creation actually taking place!!
In April each year and from North America, the Eagle first becomes visible in the early morning hours (just before sunrise), then progresses to full evening views beginning in June and continuing through August. It then retreats into the dusk of evening sunsets in October and finally disappears in November, not to return until the early mornings of the following April.
In the amateur image included here, the Pillars of Creation are clearly visible within the heart of the nebula. In addition to the above heroic story, they stand as a testament to recent technological advancements in astronomical science, both within the ranks of the professional astro-scientific community, but also among amateur astronomical enthusiasts. The Pillars represent a "pinnacle" in photographic excellence for many aspiring astrophotographers as they seek to develop their craft.