John C. Barentine's Personal Website
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Astronomy

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These pages highlight some of my amateur astronomy work in recent years. I call my home observing site in Tucson, Arizona, the Silverado Hills Observatory. It is located on the traditional lands of the Tohono O'odham, O'odham Jewed, Hohokam and Sobaipuri peoples. They, too, were and are astronomers and carried out observations of the heavens from this place. I am humbled to merely walk in their footsteps and look in wonder at the same skies.
I am a primarily visual observer. My main instrument is a home-built 20 cm f/3.8 Newtonian telescope. I have also done some astrophotography but don't really consider myself an astrophotographer. The image at left is of the star Spica (α Virginis) made through my scope.
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Carbon Star List

This page contains a list of 164 carbon stars ranging in brightness from +4.5 (U Hydrae at maximum light) to +18.0 (SU Tauri at minimum light) that make for good targets with small telescopes. These stars often show intense colors through the eyepiece, ranging from pale pink to bright orange to deep, saturated red.
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The Bluest Hipparchos Stars

This list of 11 stars is the result of an experiment to try to visually detect the colors of the brightest, bluest stars I could find. After observing a number of carbon stars, which are among the visually reddest objects in the night sky, I started to wonder about the opposite end of the spectrum. But it turns out that there are very few stars that are blue enough, and bright enough, to convey a sense of intense, saturated color to the eye. 
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Astronomical Visibility

What is the faintest star one can see from a night sky of a given brightness with a telescope of a particular aperture? That is a surprisingly complex question whose answer touches on principles of both modern vision science and perceptual psychology. In this project, I came up with a method to test my visual threshold against the capabilities of my telescope and typical site conditions in order to make a better estimate than observing individual stars in isolation.
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Lunar Domes

As our nearest neighbor in space, the Moon is a rich and rewarding target for observations with small telescopes. Evidence of the Moon's past as a geologically active world takes many forms, including the presence of small volcanoes known as 'domes'. This page describes lunar domes in the context of the Moon's geologic history, provides tips and tricks for seeing these features and features a list of the top 10 best domes on the lunar nearside to observe with backyard telescopes.
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Beyond the Lunar 100

Just when you think you've seen every interesting lunar feature, you spot yet another that's both fascinating and more or less known. That was my feeling after completing the "Lunar 100" features of note, so I started compiling my own list. It contains a variety of features that illustrate captivating and often weird highlights of the Moon's geologic history. "Beyond the Lunar 100" offers Moon enthusiasts something new to look for.
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Astrophotography

Some astronomical images I have captured over 30+ years using equipment from film cameras to 4-meter-class telescopes.
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  • Home
  • Bio
  • CV
  • Media
  • Outreach
  • Photos
    • South Africa 2024
    • Austria 2024
    • Germany 2019
    • Hungary 2019
    • Taiwan 2018
    • New Zealand 2018
    • UK 2017
    • Wyoming Eclipse 2017
    • Catalonia 2017
    • Romania 2016
    • Japan 2016
    • Korea 2014
  • Astronomy
    • Carbon Star List
    • The Bluest Hipparchos Stars
    • Astronomical Visibility
    • Lunar Domes
    • Beyond The Lunar 100
    • Astrophotography
  • Research
    • Earthshine
    • Skyglow
    • Satellite Megaconstellations
    • Night Sky Photometers
    • SN 1006 Petroglyph
  • Papers
  • Books
    • Ashen Light of Venus
    • The Lost Constellations
    • Uncharted Constellations
  • Contact