At the center of our Galaxy liesGroup of answer choicesa black hole of millions of solar masses.a huge emission nebula.the largest of all globular clusters.a quasar.an intensely bright visible superstar.

It now seems highly likely that in the center of most galaxies is to be foundGroup of answer choicesa super-massive black holea neutron stardusta stellar-mass black hole

The largest known black holesGroup of answer choicescan be no bigger than the earth, like white dwarfs.can be no more than 1.4 solar masses, according to Chandrasekhar.lie in the cores of the most massive galaxies.can be no bigger than a small city, just like neutron stars.create the dark nebulae in the plane of the Milky Way.

You are looking at an image from a space telescope and you see billions of stars revolving around a central location. What have you discovered?bd77bd293067382568bc14f56bb7be1d.webm128 KB aa black hole ba planetary nebula ca main sequence star da galaxy

Most of the mass of the Milky Way seems to exist in the form ofGroup of answer choicespopulation II stars in the Halo.the black hole in the Galactic Center.hydrogen gas in the disk and spiral arms.dark matter out in the Halo.population I stars in the disk.

Recall which of the following is made up of the Milky Way, the Andromeda galaxy and a few smaller galaxies. The Interstellar NeighbourhoodThe Local GroupThe Virgo SuperclusterThe universe