How do astronomers know that the luminous regions of active nuclei of active galaxies are very small?
a. Their nuclei are much brighter than expected.
b. The orbits of stars near the center of the galactic nuclei are faster than expected.
c. The luminosity of the nuclei varies over short times.
d. The color of the nuclei is different than expected.
Question 2
Synchrotron radiation is produced
a. in planetary nebulae.
b. by red dwarfs.
c. in massive stars as their iron core collapses.
d. in supernova.
e. by neutrinos.
Total fertility rates (TFRs) among major regions of the world.
Part of the Hubble Ultra-Deep Field image showing a typical section of space containing galaxies int
The functional regions of the cerebrum.
Regions of the Human Visual Cortex and Their Functions
The regions of the human X chromosome distinguished by its banding pattern
Functional Regions of the Human Brain