Mapping the cosmos with Cepheid stars. Strong aurorae dazzle astronauts on space station. Long trips to space linked to possible brain damage. First crewed Artemis Moon landing delayed until at least Gift ideas for astronomy lovers and stargazers — holiday gift guide. Snapshot : ALMA spots moon-forming disk around distant exoplanet. The first 'space hotel' plans to open in Cosmos: Origin and Fate of the Universe. Astronomy's Moon Globe. Galaxies by David Eicher. Astronomy Puzzles. Jon Lomberg Milky Way Posters.
Astronomy for Kids. Want to leave a comment? Only registered members of Astronomy. Registration is FREE and only takes a couple minutes. Login or Register now. Most recent Oldest to newest. How would a human body decompose on Mars? Elizabeth Howell is a contributing writer for Space.
She is the author or co-author of several books on space exploration. Elizabeth holds a Ph. She also holds a bachelor of journalism degree from Carleton University in Canada, where she began her space-writing career in Besides writing, Elizabeth teaches communications at the university and community college level, and for government training schools.
To see her latest projects, follow Elizabeth on Twitter at howellspace. Elizabeth Howell. Leavitt received an appointment as a research assistant at the Harvard College Observatory in Cambridge in This was a voluntary post; her assignment was to determine stars' magnitudes by consulting photographs of the heavens. Her work impressed the staff. She was given a permanent position in by Edward Pickering, a noted astronomer who was head of the Harvard College Observatory.
Her salary was 30 cents per hour. Leavitt was one of a group of women working at the observatory who were known as computers. It has been said that Pickering hired women in order to save money because he would have had to pay men with the same education greater salaries.
Other women in this group also became well-respected astronomers, including Annie Jump Cannon and Williamina Fleming. Leavitt was soon promoted as head of the photographic photometry department. Photometry, as its name implies, is the science of measuring stars' brightness. Employing photography in astronomy necessitated adjusting astronomers' magnitude scale to compensate for the way film registers light. This post did not give Leavitt time to indulge in theoretical work.
Actually, she was given no latitude in her choice of research. Pickering would typically assign work to Leavitt on topics that interested him. In her role in the photometry department, Leavitt was assigned to search photographic plates for variable stars in the Magellanic Clouds regions. According to Astronomy, "The technique for variable hunting was strikingly uncomplicated. Leavitt would simply overlay the positive plate of a region of sky on the negative plate taken on a different night.
If the positive and negative star images didn't match up, she would flag a potential variable. By she discovered more than variable stars using this method.
The following year that number grew to more than stars. This ranking would become a standard used by astronomers, known as the Harvard Standard.
Leavitt was interested in Cepheids. These variable stars become brighter, then dim in a regular cycle. Since these stars were all roughly the same distance away, and astronomers could measure their distance in the Magellanic Clouds, this meant that future astronomers were able to use the period-luminosity relationship to figure out the distance of places where these stars were found much farther away. The longer the star took to change brightness, the brighter the star.
It is worthy of notice that the brighter variables have the longer periods. During her career, Leavitt catalogued more than 2, variable stars—about half of the known total in her day, without ever looking through a telescope. She died later that year. These women deserve their rightful place in history.
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