Shown below are parameters for our home galaxy, one of its small neighbors (the Small Magellanic Cloud), and the oxygen-poor galaxies discussed in the article. Solar values serve as the benchmark for the oxygen abundances, and masses are approximate to within a factor of 10. Although the dwarfs churn out fewer stars per year than the Milky Way (second row), they also have a lot less mass to work with (bottom). The Milky Way's gas mass here includes the disk and bulge. Small Magellanic Cloud 15% 0.04 I Zwicky 18 SBS 0335052W Leo P 2.6% 2.3% 2.6% 0.2 Leoncino Little Cub J0811+ 4730 1.8% 2.3% 1.7% 0.5 0.01 0.00004 0.001 0.0008 1011 1010 109 108 107 10 6 105 104 103 102 101 10 0 sk yandtelescope.com * A PR I L 2 018 27http://www.skyandtelescope.com