The angular measurement in hours, minutes, and seconds from the celestial prime meridian eastward is known as  _______________.

The estimated number of stars in the Milky Way is about how many billion?

The majority of stars are small, cool, type-M stars called ____________________.

The observation of parallax was experimental proof that the Earth is _______________ around the Sun.

This planet resembles the Earth in several ways – they have similar average density, mass, size and surface gravity.

This drawing can be used to show what?

The name given to the point of a planet’s orbit that is closest to the Sun is _____________.

Kepler’s first law states that the orbits of the planets around the Sun are ____________

The terrestrial planets have ______________________.

The bronze doors of the Abbey Church of Saint Michael (10.27) were commissioned by _______.