Appendix A -- Column Headings

CATALOG -- Messier Catalog number

COMMON NAME -- Common name given to object

TYPE -- OC: Open Cluster, PN: Planetary Nebula, BN: Bright or Emission Nebula GC: Globular Cluster, followed by roman numeral for Shapley and Sawyer classification, EG: Elliptical Galaxy, SG: Spiral Galaxy IG, IG: Irregular Galaxy, AS: Asterism

CONSTLN -- Constellation where the object is found, using the IAU three letter abbreviation

DISTANCE thousands of LY -- Distance from Earth expressed in thousands of light years. Distances were taken from Wikipedia articles of each object. Keeping track of this statistic taught me a lesson in perspective. Planetary nebula are our closest Messier neighbors. They are no doubt common throughout our galaxy and other galaxies, but they are so dim that only the closest ones can be observed from Earth. Bright or emission orreflection nebulae are brighter and can be seen at a greater distance. Open clusters can be seen much further out, probably only limited by the ability to resolve individual member stars. Globular clusters which tend to be found in  a halo around the core of the Milky Way are even further away, but still within our galaxy. Globulars have been observed in other galaxies of the Local Group, but were not detectable with the telescopes of Messier's day. Spiral, elliptical and irregular galaxies are the farthest Messier objects.

MAGNITUDE -- Relative brightness of each object. Data gathered from Sky & Telescope's Messier Card.

SIZE -- Apparent size of each object in arc seconds. Also from S & T Messier Card.  Magnitude and size data became invaluable to me, helping me to know "how big and how bright" was the object which I was looking for.

DATE -- Date of first observation of each object. Many of the objects have been revisited multiple times, but each listing is the first recorded observation.

TIME -- Time of observation. All times are Mountain Standard or Mountain Daylight time, regardless of the location of the observation.

LOCATION -- Observations were made at many different locations. Detailed information of each location can be found in Appendix B.

ELEVATION -- Elevation of location in feet above sea level. Data from www.freemaptools.com/elevation-finder.htm.

BORTLE -- The dark sky quality of each location measured by the Bortle Scale, with 1 being the darkest possible sky.  Bortle estimates gathered from http://darksitefinder.com/maps/world.html

CONDITIONS -- Subjective appraisal of cloud conditions.  Also unusual conditions such as smoke or dust.

SEEING -- Indication of atmospheric turbulence, bad to excellent. Data from www.cleardarksky.com, I used the chart closest to observation location.  This data is indicated on a scale of one to five, with 1 of 5 being bad and 5 of 5 being excellent. When this data was unavailable, subjective assesment made based on stellar scintillation and quality of planetary or lunar observations.

TRANSPARENCY -- Transparency of atmosphere from ground to space. Data from www.cleardarksky.com  is indicated on a scale of one to five, with 1 of 5 being poor and 5 of 5 being transparent. When this data was unavailable, subjective judgement of transparency was based on daytime observation of distant objects and limiting magnitude of dim stars.

HUMIDITY -- Factor in seeing and transparency. Lower humidity generally means better seeing conditions. Data from www.weather.gov, the National Weather Service website.  Addtional data from www.wunderground.com historical archives.

MOON% -- Percentage of Lunar illumination on date of observation. Data taken from http://www.aa.usno.mil/data/docs/RS_OneDay.php  (U.S. Naval Observatory Complete Sun and Moon Data for One Day). At remote locations, data is from closest major city. New=new moon.

RISE/SET -- Time (local time zone) of Moonrise or Mooset (R=rise, S=set) on the date of observation. Also from USNO website. New=new moon.

EQUIPMENT -- Telescope or binoculars and eyepiece(s) used for each observation.  Equipment details on this page.

MAGNIFICATION -- Magnification of binoculars or telescope/eyepiece combination.

FOV (degrees) -- Actual field of view, expressed in degrees.

COMMENTS -- My personal notes describing each object. Brief notes are taken from my observation journal. About halfway into the project I began using a digital voice recorder to document my observations, which were later transcribed intomy journal. I have not included my complete journal as it is nearly one hundred pages in length and includes Lunar, planetary, NGC and double star observations in addition to my Messier observations. I am currently in the process of putting my full journal online on my personal website. I will provide more detailed observation notes upon request.

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