The Milky Way
 
The outline 1 and shade 1 are based on the book 'Uranografia, Descrição do Céu', by R.R. de Freitas Mourão, a Brazilian astronomer. The equatorial coordinates were manually taken from his maps. Then, they were converted to galactic coordinates using Microsoft Excel and manually inserted onto a bitmap as black pixels over a white background. The bitmap dimensions were 450 by 3600 pixels, making each pixel correspond to 0.1 degree. The pixels were manually connected (and their connections smoothed) using Adobe Photoshop 3.0. That created the base for outline 1. Finally, the space between the two curves defining outline 1 was filled with black pixels, creating the base for shade 1.

The outlines and shades 2 to 5 are based on a photomosaic of the Milky Way created by the German astrophotographer Axel Mellinger. The original picture, dowloaded from his website (http://canopus.physik.uni-potsdam.de/~axm/astrophot.html), was 300 by 2400 pixels in size. It was expanded to 450 by 3600, using Adobe Photoshop. Still in Adobe Photoshop, an 1 pixel  'minimum' filter was applied to eliminate individual star images. After some adjustmests in brightness and contrast and conversion to a grayscale bitmap, a 2 pixels 'gaussian blur' filter was used to create a 'cloudy' aspect. Then, a 'trace contour' filter was applied in four brightness levels, creating the bases for outlines 2 to 5. These were filled with black pixels, creating the bases for shades 2 to 5.

Once the base bitmap files had been created, an application written in Microsoft Visual Basic 6.0 was used to scan the images, find black pixels, get their coordinates in pixels, convert them to galactic coordinates and then to equatorial coordinates which were sent to text files. These are the DAT files included in MWSMP6.ZIP. 

The average distance between each point in the outlines is 0.1° or 6'. For the shades, it is 0.4º or 24'.

José R. Vieira, Sao Paulo, Brazil, Feb/2000
