Which of these stars lies closest to the north celestial pole on the celestial sphere?
A) Deneb
B) Alpha Centauri
C) Spica
D) Sirius
Question 2
Which of the following best explains why the Moon's orbital period and rotation period are the same?
A) The Moon once rotated faster, but tidal friction slowed the rotation period until it matched the orbital period.
B) The Moon was once closer to Earth, but the force of gravity got weaker as the Moon moved farther away.
C) The law of conservation of angular momentum ensured that the Moon must have the same amount of rotational angular momentum as it has of orbital angular momentum.
D) The equality of the Moon's orbital and rotation periods is an extraordinary astronomical coincidence.
Species richness of birds in North America.
Charles Darwin may be dead and gone but a recent write-in campaign has pitted him against Republican
Major trunk lines carrying long-distance traffic crisscrossed the area east of the Mississippi. The
Richmond, Virginia, lies in ruins in April 1865 at the time of Lincoln’s visit—and a few days before
Black and White Out-Migration from Virginia and North and South Carolina, 1870–1940 (in thousands)
Major Topographic Divisions of the North Atlantic Ocean