The Pillars of Creation

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    By Gary J. Becker, MD, former ABR Executive Director

    Time for astrophotos. I really love to photograph the objects in this image. Each time I try to improve, and this time, I also wanted to use my newest telescope. I believe the result is the best I’ve obtained to date. I acquired the individual frames used to create the final image at my remote observatory in Benson, AZ between midnight and 4:30 a.m. on the mornings of April 25 & 26, 2020. Messier 16 (M16; the Eagle Nebula or the Star Queen Nebula) includes both the open star cluster (NGC 6611) and the emission nebula, star-forming region IC 4703. It can be found in the direction of the constellation Serpens Cauda (Tail of the Snake) in the spring and summer night skies of the Northern Hemisphere, at a approximately 6,500 light-years (38 quadrillion miles) from Earth. This is approximately one fourth as far as Earth’s distance from the Milky Way’s galactic nucleus.

    Each pillar is a stellar nursery, consisting of extremely cold, dense gas clouds and collectively, molecular clouds. The longest of the uniquely shaped pillars is approximately 9.5 light-years (56 trillion miles) tall. Here’s how star formation occurs inside molecular clouds: At 10-20oK (just above absolute zero), eventually the density of a cloud region exceeds a threshold and the cloud collapses under the force of its own gravity. This process drives up the temperature and pressure deep within the cloud, igniting nuclear fusion. Once fusion begins, the star formation process is underway. Most of the very large bluish white stars that form the open cluster NGC 6611 in the first image below are extremely hot, very young–5 million years old or less—and produced by this very process. Such stars also have a short lifespan (millions of years, instead of billions of years like our Sun) and emit very high-energy ultraviolet radiation that excites neutral hydrogen gas (HI, pronounced “H one”) to the ionized (HII, pronounced “H 2”) state. Upon return of the electrons to their lower energy state, a characteristic wavelength (656.3 nm) of red light is emitted, resulting in the red appearance of emission nebulas such as this one, IC 4703. My CCD camera connected to the telescope has a hydrogen-alpha filter to capture light of this wavelength. A few million years from now, any portion of the molecular cloud not already consumed in star formation will have been dispersed by the powerful stellar winds from the hot blue stars. When the molecular cloud is gone, only the open star cluster NGC 6611 will remain (albeit with the addition of some more new stars).

    In processing the image, I did some software manipulation to minimize the presence of the stars, both in size and number. This was for the purpose of accentuating the morphology of the molecular clouds (pillars).

    Emission nebula IC 4703 entered the popular culture as “The Pillars of Creation” in 2015, following the publication of an iconic HST (Hubble Space Telescope) image in conjunction with the 25th anniversary of the HST launch. The clarity of the Hubble image can’t be beat. After all, it is a space telescope unencumbered by the atmospheric distortion that plagues every ground-based device, including my amateur telescope. Nevertheless, my scope and camera manage to produce a very recognizable and satisfactory image of M 16. As far as the different colors in the Hubble image are concerned, the Hubble image represents predominantly infrared wavelengths of light. My telescope and camera setup does not image infrared, ultraviolet, x-ray, or radio- wavelengths. Rather, it “sees” only visible light. The other thing to keep in mind when you are viewing other professional astrophotos is that sometimes, false colors are used to represent wavelengths not ordinarily visible to the human eye. Usually, that is explained to the viewer/reader.

     

    For the Techno-Geeks:

    Paramount ME German Equatorial mount

    Celestron C14 telescope and Focal reducer, for effective f/6.7

    QSI 683 CCD Camera

    Focal length: 2365 mm

    Pixel size: 0.47 arcseconds per pixel

    FOV: 26.2’ Width x 19.6’ Height

    Astrodon filter set; each filter (Hydrogen Alpha, Red, Green, Blue, Luminance) utilized separately

    Total imaging acquisition time: 82 images x 180 sec per image: 4 hours, 06 minutes

    Binning: All R,G,B and H-alpha images binned 1×1

    Microtouch Automatic Focusing motor

    Autoguiding with Orion guidescope and Starlight Xpress Lodestar X2 camera

    Planning Software: CCD Navigator, Megastar, ACP Planner

    Remote access: Teamviewer and GoToMyPC

    Acquisition software: TheSkyX Pro, Maxim-DL6, FocusMax 4, ACP Observatory Control

    Image processing software: Pixinsight, Adobe Photoshop & Adobe Lightroom 2020

    RA Center: 18h 18m 52.3s

    Dec: -13o:47’:59”