Double Stars greeting card by The Pattern Book

Adapted from Camille Flammarion’s 'The Marvels of the Heavens' (1870). While double stars often occur as binary pairs (two stars bound in gravitational orbit with one another) they can also form optical doubles, whereby two stars at great distance from one another align by chance in the line of sight of the observer. Multiple stars (three or more) are classed in the same way as doubles.

Image courtesy The Library of Congress. 170mm x 120mm (6 3/4" x 4 3/4"). Blank inside. Individually wrapped in a compostable bag with a 120gsm recycled kraft envelope. Printed with vegetable-based inks on a carbon neutral press using responsibly sourced, 300gsm Italian paper.