Dark Matter
In 2008 a study was published that appeared to show that M94 had very little or no dark matter present. The study analyzed the rotation curves of the galaxy's stars and the density of hydrogen gas and found that ordinary luminous matter appeared to account for all of the galaxy's mass. This result was unusual and somewhat controversial, as current models don't indicate how a galaxy could form without a dark matter halo or how a galaxy could lose its dark matter. Other explanations for galactic rotation curves, such as MOND, also have difficulty explaining this galaxy. This result has yet to be confirmed or accepted by other research groups, however, and has not actually been tested against the predictions of standard galaxy formation models.
Read more about this topic: Messier 94
Famous quotes containing the words dark and/or matter:
“No matter how deep and dark your pit, how dank your shroud,
Their heads are heroically unbloody and unbowed.”
—Ogden Nash (1902–1971)
“But no matter how they make you feel, you should always watch elders carefully. They were you and you will be them. You carry the seeds of your old age in you at this very moment, and they hear the echoes of their childhood each time they see you.”
—Kent Nerburn (20th century)