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Stars of the Universe (January 17, 2003, Two)

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Program Summary

Everyone knows the name Albert Einstein. His theory of relativity changed our world forever. But few of us ever look beyond this famous genius to learn about the work of other bright lights without which Einstein could not have developed his revolutionary ideas. Nor does the world of cosmology end with Einstein. Astonishing discoveries, built on his body of work, continue to be made by scientists of every nation. Let’s look at some who may not be household names, but have made their mark on cosmology.

Born in an era when women rarely went to college, Henrietta Leavitt (1868–1921) not only did just that, she also chose to enter a field that is difficult for anyone. She volunteered at the Harvard College Observatory for seven years before she was finally hired at the rate of 30 cents an hour. Leavitt was not permitted to choose her projects; rather she had to research whatever the director told her to. She did become head of the photographic photometry department, which studied photos of stars to determine their magnitude. She also discovered 2,400 variable stars called Cepheids, the light from which intensifies and decreases on a regular basis. This led her to discover the correlation between the time it took a star to wax and wane to that star’s actual brightness, making it possible to measure the distance to it. Without this discovery, Edwin Hubble could never have done his groundbreaking work.

If that name sounds familiar, it’s because the Hubble telescope is named for him. Edwin Hubble (1889–1953) was an accomplished scholar who held an undergraduate degree in astronomy and in mathematics, a legal degree, and a Ph.D. in astronomy. He was also a Rhodes scholar. Working at the Mt. Wilson Observatory in California, Hubble discovered a Cepheid (variable star) in the Andromeda nebulae. Measuring the distance to that star (using Henrietta Leavitt’s system), Hubble realized that it was much farther away than previously thought and that the nebulae were not contained in our galaxy, but in another one outside the Milky Way. No one had ever imagined that other galaxies existed. The Universe had suddenly expanded. Hubble also discovered that galaxies were moving away from each other. Hubble’s Law states that these galaxies recede at a rate constant to the distance between them, and the further away they were, the faster they receded. He then calculated the point at which the expansion began, fixing it at about 2 billion years ago.

In contemporary times, Japanese-American Michio Kaku is known for being a co-founder of string theory (see below for more about string theory). Growing up in San Francisco, Kaku loved visiting the Japanese gardens, especially the koi pond, where he wondered if the fish knew there was another universe beyond their world of water. When the U.S. entered World War II, he and his parents were sent to an internment camp in the southwest for the duration of the war. Kaku graduated from Harvard, earned a Ph.D. from the University of California at Berkeley and has been a professor at New York University for 25 years. Kaku has dedicated his career to picking up where Einstein left off: finding a theory of all fundamental forces, or a “theory of everything.” He is a pioneer of superstring theory, a view of the universe in which all matter is composed of sub-atomic, vibrating strings in 10-dimensional space. When he hits the theoretical wall, Kaku likes to ice skate; out there, he says, “It’s just me and Isaac Newton.”

Neil deGrasse Tyson (1959– ), noted African-American astrophysicist, was born in the Bronx, New York, and became enthralled with the stars at a young age. Though he says his community expected African-American boys to become athletes, he preferred books and was determined to become an astronomer. He earned degrees from Harvard and University of Texas at Austin and a Ph.D. from Columbia University. In 1996, he was appointed director of the world-famous Hayden Planetarium at the American Museum of Natural History in New York City, the youngest person ever to be given that position. He is particularly interested in dwarf galaxies, exploding stars, and the evolution of the bulge in the Milky Way. His career has not always gone smoothly, however. Despite his education and position, he says he is still treated with the suspicion that his race can arouse in some Caucasians and that more is expected from him because he is African-American. “There’s an extra social tax I have to pay. It’s not a burden, I just pay the tax.”

Guests

Related Links and Resources

Astronomical Society of the Pacific: Women in Astronomy: An Introductory Resource Guide. A comprehensive list of well-known women astronomers.

University of Buffalo, Department of Mathematics: Who are the Black Astronomers and Astrophysicists? Excellent resource for researching African-American men and women in astronomy and cosmology.

PBS: NOVA Online/Einstein Revealed. For a fascinating story of Albert Einstein’s life and work.

The Official String Theory Web Site. Learn more about Michio Kaku’s work.

ABCNews.com, Nov. 22, 2000: Science or Sci Fi? Chris Wallace interviews Michio Kaku about wormholes, time travel, extraterrestrial life, and other subjects straight from “Star Trek.”

Me and Isaac Newton: Guide for Educators. This guide accompanies the HBO film by the same name, which follows Michio Kaku and six other contemporary scientists and records their work and thoughts.

For Discussion:

• Why do you think women used to be discouraged from pursuing an education?
• How have things changed in this country for women and minorities in the sciences? Do you think it’s still more difficult for them to succeed than for white males?
• Women and minorities are most visible in the area of space flight. Who was the first female astronaut? The first African-American astronaut? The first Asian-American astronaut? The first Hispanic-American astronaut? What were the years they first went into space?

Activities

Who’s who. Have students choose a pair of female or minority astronomers (one from the past, one from the present) to profile. Have them compare and contrast the pair’s experiences in getting an education and pursuing a career.

A different world. Students can visit the SEED People (Schlumberger Excellence in Educational Development) page, which contains interviews with men and women in science and technology of all races and ethnicities. Have them chose a female or minority scientist to write to about their experiences.

Use the search box below to perform a Google search within any of the specifc sites or general domains mentioned in this Activities section.

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