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Margaret Hamilton was the director of Apollo’s onboard computer software programming, overseeing a team of one hundred e...
06/23/2026

Margaret Hamilton was the director of Apollo’s onboard computer software programming, overseeing a team of one hundred engineers. Developing the software for the Moon landings involved writing code by hand, transferring the code to punch cards, and then feeding the cards to a mainframe computer for compilation, which converted the code into machine-readable instructions. Computer printouts allowed Hamilton and her team to debug the code line-by-line. Because of her rigorous, extremely reliable code, no bugs were ever found in the onboard flight software. As she said, “There was no second chance.”

—Adapted from THE PROMISE OF A NATION, 1960s: "Age of Possibility" by Teasel Muir-Harmony, p. 252

Fun fact: Hamilton also coined the term "software engineering"! Read all about the Apollo 11 mission and what it meant to the people who watched and worked on it in THE PROMISE OF A NATION!

https://www.smithsonianbooks.com/store/smithsonian/the-promise-of-a-nation-commemorating-250-years-of-patriotism-resilience-and-aspirations-from-the-national-collection/

Image credit: Margaret Hamilton. Draper Laboratory, public domain, via Wikimedia Commons.

On June 18, 1976, scientists from the Smithsonian Astrophysical Observatory and NASA launched Gravity Probe A. The goal ...
06/18/2026

On June 18, 1976, scientists from the Smithsonian Astrophysical Observatory and NASA launched Gravity Probe A. The goal of the experiment was to test the equivalence principle, a central feature of Einstein's theory of relativity that predicts that space-time is "warped" or "curved" under the influence of massive gravitational bodies, and therefore time progresses at a different (faster) rate where gravity is weaker. This phenomenon is also known as gravitational redshift or time dilation.

GP-A was launched from Virginia into an elliptical flight path over the Atlantic, reaching a maximum altitude of 6,200 miles (10,00 km) over the course of almost two hours. It carried a hydrogen maser (Microwave Amplification by Stimulation Emission of Radiation), an atomic clock device used to measure time precisely at an extremely small scale. By comparing that maser's measurements transmitted over the course of its trip to those of an identical reference maser at the Kennedy Space Center, researchers were able to confirm slight changes to the clock's rate in lower gravity. In fact, the Gravity Probe A experiment confirmed scientists' expectations about the scale of the redshift effect to an accuracy of 0.02%.

A more complex experiment, Gravity Probe B, was launched to confirm and expand on these findings in 2004, among other experiments. However, the plot continues to thicken: modern quantum mechanics theories do often require the equivalence principle to be violated at some scale.

Photos:

1) Gravity Probe A payload of 1976 with designers Robert Vessot and Martin Levine of the Smithsonian Astrophysical Observatory. ©ESA, credit to https://einstein.stanford.edu

2) Courtesy of Benjamin Crowell via Wikimedia Commons, https://en.wikipedia.org/wiki/Gravity_Probe_A #/media/File:Benjamin_Crowell,_General_Relativity_(2009)_p17_GPA.gif , CC BY-SA 4.0, https://creativecommons.org/licenses/by-sa/4.0/

3) Courtesy of NASA, image credit to Paul Ehrensberger, Stanford University.

Sources: https://web.archive.org/web/20110918231727/http://funphysics.jpl.nasa.gov/technical/grp/grav-probea.html , https://www.npl.washington.edu/eotwash/equivalence-principle , https://einstein.stanford.edu/content/faqs/gpa1.html , https://www.esa.int/ESA_Multimedia/Images/2015/11/Gravity_Probe_A , https://images.nasa.gov/details/0400532

June 17th is National Eat Your Vegetables Day. An important message, to be sure—but no one ever said it had to be a chor...
06/17/2026

June 17th is National Eat Your Vegetables Day. An important message, to be sure—but no one ever said it had to be a chore! The SWEET HOME CAFÉ COOKBOOK provides plenty of options for getting your veggie vitamins in as deliciously as any dessert-y indulgence.

With 109 recipes, this sumptuous cookbook takes readers on a unique journey through the salads, sides, soups, snacks, sauces, main dishes, breads, and sweets that emerged in America as African, Caribbean, and European influences blended together. Featured recipes include Pea Tendril Salad, Fried Green Tomatoes, Hoppin' John, Sénégalaise Peanut Soup, Maryland Crab Cakes, Jamaican Grilled Jerk Chicken, Shrimp & Grits, Fried Chicken and Waffles, Pan Roasted Rainbow Trout, Hickory Smoked Pork Shoulder, Chow Chow, Banana Pudding, Chocolate Chess Pie, and much more.

Hungry yet? Buy your copy today and veg out in style!

https://www.smithsonianbooks.com/store/national-museum-african-american-history-and-cultu/sweet-home-cafe-cookbook-a-celebration-of-african-american-cooking/

Happy Pride Month! Our latest backlist pick is a fascinating exploration of q***r history and art: HIDE/SEEK.This collab...
06/16/2026

Happy Pride Month! Our latest backlist pick is a fascinating exploration of q***r history and art: HIDE/SEEK.

This collaboration with the National Portrait Gallery traces the defining presence of same-sex desire in American portraiture through a vibrant selection of more than 140 full-color illustrations, drawings, and portraits from leading American artists. Arcing from the turn of the twentieth century through the emergence of the modern gay liberation movement in 1969, the tragedies of the AIDS epidemic, and to the present, HIDE/SEEK considers the influence of gay and le***an artists in creating American modernism. Explore how questions of gender and sexual identity dramatically shaped the artistic practices of influential American artists such as Thomas Eakins, Romaine Brooks, Marsden Hartley, Georgia O'Keeffe, Charles Demuth, Jasper Johns, Robert Rauschenberg, Andrew Wyeth, Andy Warhol, Robert Mapplethorpe, and many more—in addition to artists of more recent works such as Felix Gonzalez-Torres, Glenn Ligon, Catherine Opie, and Cass Bird. You don't want to miss it!

https://www.smithsonianbooks.com/store/art-architecture/hideseek-difference-and-desire-in-american-portraiture/

June 15th is Nature Photography Day! Every October, the Natural History Museum, London, grants the Wildlife Photographer...
06/15/2026

June 15th is Nature Photography Day! Every October, the Natural History Museum, London, grants the Wildlife Photographer of the Year Award to around 17 category winners whose photographs astound us, amuse us, and help us to better understand a species's role in the natural world. It's the world's largest photography competition, with more than 60,000 annual entries.

Published in collaboration with the Natural History Museum, London, 60 YEARS OF WILDLIFE PHOTOGRAPHER OF THE YEAR showcases more than 230 of these intimate, otherworldly, and poignant moments—alongside fascinating commentary on the history of nature photography and insight into the photographers' artistic techniques and strategies.

https://www.smithsonianbooks.com/store/science-nature/60-years-of-wildlife-photographer-of-the-year-how-wildlife-photography-became-art/

Images shown, credit to the photographers:

1) Photo by Jean-Louis Klein and Marie-Luce Hubert, France, 1994

2) Photo by Bence Máté, Hungary, 2002

3) Photo by Zorica Kovacevic, Serbia/USA, 2019

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