Accessory to War: The Unspoken Alliance Between Astrophysics and the Military is the fifteenth book by American astrophysicist and science communicator Neil deGrasse Tyson which he co-wrote with researcher and writer Avis Lang.

[1] The book chronicles war and the use of space as a weapon going as far back as before the Ancient Greeks, and includes examples such as Christopher Columbus' use of his knowledge of a lunar eclipse and the use of satellite intelligence by the United States during the Gulf War.

[2][3] While speaking on the book, Tyson told National Geographic that he regards the collaboration between science and the military as a "two-way street.

"[4] Marcelo Gleiser wrote that the book "rings like a wake-up call, even if an uncomfortable one.

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