Leavitt noticed that distant stars beamed from “bright” to “cold” at varying rates.

Sean Fanning has done it again. The Designer of the Year for 2016 converted Lamb’s Players’ stage into the Harvard Observatory.

Laura Gunderson’s Silent Sky begins early in the 20th Century. Harvard has the state-of-the-art telescope: the 15´ “Great Refractor.” Fanning creates the dome above it, dark, wood-paneled walls, and various arches (the dome, doorways, half of the circular floor). But no telescope. Where’s the vaunted Refractor? As the play proceeds, the omission becomes an apt choice.

Henrietta Swan Leavitt never got to see it either. When she worked at the observatory, Leavitt (1868–1921) discovered something few thought possible: the universe didn’t stop at the Milky Way — it went far beyond. Even more: the core of the Milky Way was not the center of the universe. Her discovery would make the third great leap in astronomy: from the Earth at the center of the universe and then the sun. She theorized an endless Out There — but couldn’t prove it. The telescope was off limits to women.

Silent Sky is the Hidden Figures of astronomy. In the movie, African-American women work, in a segregated area, as “computers” (“people who compute data”) for the space program. Katherine Johnson, math whiz, calculates the flight trajectories for Project Mercury. The women had two strikes against them: they were female and they were black. Levitt had two against her as well: she was a young woman and nearly deaf. Make that three: she trusted her instincts and spoke her mind.

Like Katherine Johnson, Henrietta Leavitt received little credit for her discovery. Prior to it, one could only measure nearby stars. Using a “spanker” — a square magnifying glass — she and other women studied photographic plates of more distant stars. Leavitt noticed that they beamed from “bright” to “cold” at varying rates. The differences let her calculate their distances from Earth. Problem solved. But male scientists took her findings without mentioning her work. In 1923, Edwin Hubble studied star V1 and proved the Andromeda Galaxy lay beyond the Milky Way.

In Silent Sky, Leavitt has a phobia for normalcy. Unlike her conventional sister, Margaret, who marries and raises a family back in Wisconsin, Henrietta dreams huge. Only the “exceptional” will do. Margaret repeatedly urges her sister to come down from the clouds — er, universe.

Which raises the question: has anyone ever thought bigger?

At Lamb’s, her hair coiffed like a turban, Rachael Van Wormer gives Henrietta grand emotional size. She takes the largest steps and often windmills her arms to express her aims. In a fine, fearless performance, Van Wormer rightly shows that, for Henrietta, even a theater is too confining.

It’s as if she were born into a trap. Henrietta rebels against every limit. Though she knows little of the world (not even how love feels) it’s not enough. Plus, she has “fundamental problems with the state of knowledge.”

Offered a work-for-free post at the observatory, she spends her dowry to attain it. Once there, she shares an office with other women studying minuscule dots on glass plates. In effect, they count and label a star’s relative brightness and must resist “the temptation to analyze.”

The other two women, Annie Cannon and Williamina Fleming — both famous in hindsight — accept restrictions (prissy Annie even abhors “bloomers” and “dancing”). Annie and Williamina just “bookkeep the stars,” while Henrietta, who combines an omnivorous hunger for truth with a sense of destiny, can’t resist temptation and shoots the known universe beyond the Milky Way.

Silent Sky has a strong first act, as Henrietta wrestles with balky evidence and male nay-sayers, and not much of a second. The climax, her breakthrough, takes place during the intermission. The much shorter Act Two plays like a denouement. It fills in loose ends and raises some important questions but with little build. The playwright uses the standard formula for theatrical biographies: move point by point and account for all the stages of a life. But few lives match that blueprint. This approach in Sky undercuts a sustained dramatic arc.

In a comic sub-plot, Sky spends a great deal of time with Peter Shaw’s bumbled attempts to woo Henrietta. These allow her heart to thaw but become predictable — even the surprise revelation in Act Two. As Shaw, Brian Mackey gets some well-earned laughs but must jump from ungainly oaf to Shaw’s bullish alter-ego — empowered male ablaze — and back. The leaps are too extreme. Starting with less cartoony choices might help.

One of the best parts of the play and production: how Henrietta’s colleagues grow to accept her. Talk about heading into a trap. Williamina Fleming (Deborah Gilmour Smyth) and Annie Cannon (Cynthia Gerber) are hyper-territorial. Like men in ankle-length dresses, they are the rules. As their respect for Henrietta increases, they open up, delightfully.

Leavitt died of cancer in 1921. In 1923, Hubble said she deserved the Nobel Prize. Eyebrows rose throughout the scientific community: Who? Wait — a woman? Highly respected Swedish mathematician Gosta Mittag-Leffler recommended her. Both were too late. The Nobel committee never awards the prize posthumously.

Silent Sky, by Lauren Gunderson.

Lamb’s Players Theatre, 1142 Orange Avenue, Coronado.

Directed by Robert Smyth; cast: Cynthia Gerber, Catie Grady, Brian Mackey, Deborah Gilmour Smyth, Rachael Van Wormer; scenic design, Sean Fanning, costumes, Jemima Dutra, lighting, Nathan Peirson, sound, Deborah Gilmour Smyth.

Playing through May 28; Tuesday through Thursday at 7:30 p.m. Friday and Saturday at 8:00 p.m. Matinee Wednesday at 4:00 p.m., Saturday and Sunday at 2:00 p.m.; lambsplayers.org.