Recent content by Ernie L

To determine the distance to NGC 4258 using water masers in the accretion disk around its central black hole, we have to rely on a) Geometry and Einstein's theory of General Relativity b) Geometry and Newton's Generalization of Kepler's Laws c) A calibration of the distance to the LMC d) A...

1. The obejct that causes the lensing effect in the case of gravitational lensing a) has to have large amounts of interstellar clouds so that refraction can occur b) has to have large amounts of interstellar clouds so that reflection can occur c) has to have a large mass d) has to be large in...

1.. HM Cancri is the binary with the shortest known period, of 5.4 minutes. What do you conclude? a. One component must be a white dwarf or neutron star. b. Both components must be a white dwarf or neutron star. c. The system must have undergone a common-envelope phase. d. [A and C] e. [B...