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; 37x300s (3.1h) 
     palette=HOO
EQUIPMENT:
​     optics=ES102CF APO / Stellarvue 1.0x fld-fltnr, FL=714mm, f/7.0
     camera=ZWO ASI2600MC-Pro
     filter=Optolong L-eXtreme Duo NB
     mount=Celestron AVX
     guiding=Orion 60x240mm scope, ZWO ASi224MC camera
SOFTWARE:
     acquisition=Stellarium, NINA, PHD2,
     processing=PixInsight (RCAstro, SetiAstro), Photoshop (APF-R, Lumenzia), LrC

Arguably the most iconic object in our nighttime skies, 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" as first imaged by the Hubble Space Telescope   ("HST") during its maiden operations 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 +8.2, 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 1½ M years old, which is appx 7½ x older than the Jurassic period of the dinosaurs here on Earth.

IMAGER'S COMMENTSThe cavity that exists in the center of the 'Eagle', and encompassing the 'Pillars' is indicative of a type of 'sectioned open-bowl', or segmented shape, made popular in the design of Christmas Tree ornaments; where a ball-shaped ornament has been cut, or sectioned to reveal an inner portion of the ornament.  Only when viewed from a front-on perspective does the open-bowl reveal the beauty to be found within.  It is this "sectioned Christmas ornament" aspect that makes the Eagle so very popular, while also being highly sought-after by amateur astrophotographers as they seek to improve their skills.  This same aspect can be found in many other DSO's, including M42 "Orion", M8 "Lagoon", M17 "Omega", C49 "Rosette", Sh2-86 "Pillars of Vulpecula", Sh2-284 "Smiling Cat", Sh2-142 "Wizard", IC1805 "Heart", and IC1848 "Soul" nebulae.   M17 "Omega", Sh2-86 "Pillars of Vulpecula" and Sh2-142 "Wizard" are oriented so-as to present only a side-on view; so, we do not get to see their inner beauty directly.  But thanks to analysis by scientists around the world who closely study them and their associated star clusters, their shape and 'open-bowls' are still known to exist.  Your host theorizes that the process of formation of these uniquely beautiful shapes occurs when a large group of stars are 'borne' into existence as an open cluster, but embedded deep inside an extra-large nebula cloud, such as within an H-II region molecular cloud.  When the new-born stars reach a maturity and strength that can no longer be contained, their combined stellar winds 'pop the bubble' and the stars 'break free' outward into outer space.  Only the thick, most heavy formations of interstellar dust and gas, held together by surface-tension-like gravity, remain as pillars, thickened remnant wall segments, and Bok globules; not unlike the shredded walls of a popped balloon.  These remnants then further erode under a constant barrage of stellar winds from new, young stars that continue to form within the depths of these remnants.  

THE EAGLE NEBULA:  HOLDS A REMARKABLE 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 the telescope's 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 failed to find the error and report it.   So, the poor decision was linked directly to the managerial pressure applied prior to launch.   It was a $95M mistake (...roughly $209M in 2026 dollars).    As NASA’s competency began to be called into question, NASA Director of Astrophysics, Charlie Pellerin stepped-up and took full responsibility.

But then, 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 envisioned to intersect until much later, and even then only for routine maintenance, 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, schedule 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 while in orbit above the Earth.   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, ...it was 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 system with a new one that was fitted with a lens assembly having this intentional off-setting error ("glasses" if you will) 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 Arizona State University's School of Astronomy, using exposures gathered from this, now maiden operation of 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 human triumph over adversity; being a trademark for which NASA is widely known.  The image has been 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 all 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" (...being an acronym for "Evaporating Gaseous Globules") where stars are being formed and borne from within.

Today, almost three (3) decades after Hester & Scowan'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.

IMAGER'S COMMENTS:
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 iconic 'Pillars' represent a "pinnacle" in photographic excellence for many aspiring astrophotographers as they seek to develop their craft.  

260620 - M16 "Eagle" nebula