Parallel Worlds by Michio Kaku Page B

bastards any way you
look at them." He was incensed that he was passed over when the Nobel
Prize was awarded to someone else for the discovery of the neutron star.)
    In 1962, the
curious problem with galactic motion was rediscovered by astronomer Vera
Rubin. She studied the rotation of the Milky Way galaxy and found the same
problem; she, too, received a cold shoulder from the astronomy community.
Normally, the farther a planet is from the Sun, the slower it travels. The
closer it is, the faster it moves. That's why Mercury is named after the god of
speed, because it is so close to the Sun, and why Pluto's velocity is ten times
slower than Mercury's, because it is the farthest from the Sun. However, when
Vera Rubin analyzed the blue stars in our galaxy, she found that the stars
rotated around the galaxy at the same rate, independent of their distance from
the galactic center (which is called a flat rotation curve), thereby violating
the precepts of Newtonian mechanics. In fact, she found that the Milky Way
galaxy was rotating so fast that, by rights, it should fly apart. But the
galaxy has been quite stable for about 10 billion years; it was a mystery why
the rotation curve was flat. To keep the galaxy from disintegrating, it had to
be ten times heavier than scientists currently imagined. Apparently, 90 percent
of the mass of the Milky Way galaxy was missing!
    Vera Rubin was
ignored, in part because she was a woman. With a certain amount of pain, she
recalls that, when she applied to Swarthmore College as a science major and
casually told the admissions officer that she liked to paint, the interviewer
said, "Have you ever considered a career in which you paint pictures of
astronomical objects?" She recalled, "That became a tag line in my
family: for many years, whenever anything went wrong for anyone, we said, 'Have
you ever considered a career in which you paint pictures of astronomical
objects?' " When she told her high school physics teacher that she got
accepted to Vassar, he replied, "You should do okay as long as you stay
away from science." She would later recall, "It takes an enormous
amount of self-esteem to listen to things like that and not be
demolished."
    After she
graduated, she applied and was accepted to Harvard, but she declined because
she got married and followed her husband, a chemist, to Cornell. (She got a
letter back from Harvard, with the handwritten words written on the bottom,
"Damn you women. Every time I get a good one ready, she goes off and gets
married.") Recently, she attended an astronomy conference in Japan, and
she was the only woman there. "I really couldn't tell that story for a
long time without weeping, because certainly in one generation . . . not an
awful lot has changed," she confessed.
    Nevertheless,
the sheer weight of her careful work, and the work of others, slowly began to
convince the astronomical community of the missing mass problem. By 1978, Rubin
and her colleagues had examined eleven spiral galaxies; all of them were
spinning too fast to stay together, according to the laws of Newton. That same
year, Dutch radio astronomer Albert Bosma published the most complete analysis
of dozens of spiral galaxies yet; almost all of them exhibited the same
anomalous behavior. This finally seemed to convince the astronomical community
that dark matter did indeed exist.
    The simplest
solution to this distressing problem was to assume that the galaxies were
surrounded by an invisible halo that contained ten times more matter than the
stars themselves. Since that time other, more sophisticated means have been
developed to measure the presence of this invisible matter. One of the most
impressive is to measure the distortion of starlight as it travels through
invisible matter. Like the lens of your glasses, dark matter can bend light
(because of its enormous mass and hence gravitational pull). Recently, by
carefully analyzing the photographs of the Hubble space telescope with a
computer,