ASP Knowledge 4

Question 1

What is the term for the point in a planet's orbit when it is closest to the Sun?

Accepted Answer

Perihelion

Answer

Perihelion is the orbital point closest to the Sun; Earth reaches perihelion in early January each year.

Question 2

Which spectral class of stars is hottest and appears bluish-white?

Accepted Answer

O

Answer

O-type stars are the hottest stars (surface temperatures above 30,000 K) and appear blue-white in color.

Question 3

What are the dark areas on the Sun's surface caused by concentrated magnetic field regions called?

Accepted Answer

Sunspots

Answer

Sunspots are temporarily cooler, darker areas on the photosphere where strong magnetic fields inhibit convection.

Question 4

What is the name of the force that keeps planets in orbit around the Sun?

Accepted Answer

Gravity

Answer

Gravity, described by Newton's law of universal gravitation and refined by Einstein's general relativity, keeps planets in their orbits.

Question 5

The Milky Way galaxy is classified as what type of galaxy?

Accepted Answer

Barred spiral

Answer

The Milky Way is a barred spiral galaxy with a central bar-shaped structure of stars from which spiral arms extend.

ASP - Astronomical Society of the Pacific Exam Practice Test