process hyg star database into a shapefile with shapely and fiona

hygxyz.py

import shapely
import fiona
from fiona import collection
import csv

star_csv = csv.reader(open('hygxyz.csv', 'rb'))

header = star_csv.next()

max_x = 10000000
min_x = -10000000
max_y = 10000000
min_y = -10000000

"""
x: 17
y: 18
"""

schema = {
    'geometry': 'Point',
    'properties': {
        'MAG': 'float',
        'COLOR': 'float',
        'NAME': 'str',
    }
}

world_width = 20037508.34 * 2

# Open a new sink for features, using the same format driver
# and coordinate reference system as the source.
with collection(
        "stars_4.shp", "w",
        crs = {
            "type": "name",
            "properties": {
                "name": "EPSG:900913"
            }
        },
        driver = "ESRI Shapefile",
        schema = schema) as sink:
    for row in star_csv:
        x = float(row[17])
        y = float(row[18])
        lon = ( ( (x - min_x) / (max_x - min_x) ) * world_width - (world_width / 2) )
        lat = ( ( (y - min_y) / (max_y - min_y) ) * world_width - (world_width / 2) )
        if row[16]:
            color_index = float(row[16])
        else:
            color_index = 0
        abs_magnitude = float(row[14])
        proper_name = row[6]
        f = {
                "properties": {
                    "MAG": abs_magnitude,
                    "NAME": proper_name,
                    "COLOR": color_index
                },
                "geometry": {
                    "type": "Point",
                    "coordinates": [lon, lat]
                }
        }
        sink.write(f)

style.mss

Map {
  background-color: #111;
}

#stars {
  marker-line-width:0;
  marker-allow-overlap:true;
  [COLOR <= 0] {
    marker-fill:#DDFFFC;
    }
  [COLOR > 0][COLOR <= 0.5] {
    marker-fill:#B9FFF9;
    }
  [COLOR > 0.5] {
    marker-fill:#FFEBA8;
    }
  [MAG < -8] { marker-width:1; }
  [MAG > -8][MAG < -6] { marker-width:2; }
  [MAG > -6][MAG < -4] { marker-width:3; }
  [MAG > -4][MAG < -2] { marker-width:4; }
  [MAG > -2][MAG < 0] { marker-width:5; }
  [MAG > 0][MAG < 0.5] { marker-width:6; }
  [MAG > 0.5][MAG < 1] { marker-width:6; }
  [MAG > 1][MAG < 3] { marker-width:7; }
  [MAG > 6] { marker-width:8; }
  [zoom > 5] {
    text-name:'[NAME]';
    text-face-name:'CMU Serif Roman';
    text-dy:15;
    text-size:12;
    text-fill:#EBEBEB;
    }
}

Finished product: http://tiles.mapbox.com/tmcw/map/map-bwmeglxc