A) To take pictures of the moon.
B) To gather and focus light.
C) To magnify objects directly.
D) To track satellites.

A) The diameter of the objective lens or mirror.
B) The length of the telescope tube.
C) The weight of the telescope.
D) The magnification power of the eyepiece.

A) Radio telescope.
B) Catadioptric telescope.
C) Refracting telescope.
D) Reflecting telescope.

A) Reflecting telescope.
B) Refracting telescope.
C) Radio telescope.
D) Catadioptric telescope.

A) The width of the lens/mirror.
B) The distance between the lens/mirror and the focal point.
C) The magnification of the telescope.
D) The length of the telescope tube.

A) To gather light from distant objects.
B) To magnify the image formed by the objective.
C) To focus light into the telescope.
D) To filter out unwanted light.

A) Focal length of objective / Focal length of eyepiece.
B) Focal length of eyepiece / Focal length of objective.
C) Focal length of objective * Focal length of eyepiece.
D) Focal length of objective + Focal length of eyepiece.

A) The steadiness of the atmosphere.
B) The clarity of the telescope lens.
C) The observer's eyesight.
D) The brightness of the target object.

A) The aurora borealis.
B) The natural light emitted by stars.
C) The reflection of sunlight off the moon.
D) Excessive artificial light that obscures the night sky.

A) Equatorial mount.
B) Lens mount.
C) Eyepiece mount.
D) Mirror mount.

A) Allows the telescope to rotate horizontally only.
B) Keeps the telescope perfectly still.
C) Tracks celestial objects as the Earth rotates.
D) Allows the telescope to move up and down only.

A) Nebula.
B) Planets.
C) The Moon's craters.
D) Double stars.

A) Planets.
B) Star clusters.
C) Nebula.
D) Galaxies.

A) Polishing the telescope lens.
B) Calculating the telescope's magnification.
C) Attaching the telescope to the mount.
D) Aligning the optical elements of a telescope.

A) To achieve the sharpest possible image.
B) To make the telescope easier to carry.
C) To protect the telescope from dust.
D) To increase the telescope's magnification.

A) Helps you locate objects in the sky.
B) Magnifies the image more than the eyepiece.
C) Automatically tracks stars.
D) Filters out light pollution.

A) Color filter.
B) Moon filter.
C) Light pollution filter.
D) Solar filter.

A) Look at a bright star.
B) Look directly at the Sun.
C) Look at a planet.
D) Look at the Moon.

A) To make the telescope more stable.
B) To prevent dew from forming on the lens.
C) To protect the telescope from rain.
D) To block out light pollution.

A) During the day.
B) After the sky is completely dark.
C) During twilight.
D) As soon as the sun sets.

A) Traveling between different star systems.
B) Observing shooting stars.
C) Using a star chart to find faint objects.
D) Observing stars with a binocular.

A) Parsecs.
B) Astronomical Units (AU).
C) Millimeters or Inches.
D) Light-years.

A) Huygenian eyepiece.
B) Plossl eyepiece.
C) Wide-field eyepiece.
D) Orthoscopic eyepiece.

A) Schmidt-Cassegrain telescope.
B) Dobsonian telescope.
C) Newtonian telescope.
D) Maksutov-Cassegrain telescope.

A) Use your breath and a clean shirt.
B) Use regular household cleaner.
C) Use a specialized lens cleaning solution and cloth.
D) Use a paper towel.

A) The maximum magnification of the telescope.
B) The brightest star visible through the telescope.
C) The distance the telescope can see.
D) The faintest star visible through the telescope.

A) Electromagnetic radiation.
B) Gravitational waves.
C) Atmospheric turbulence.
D) Solar flares.

A) Drawing pictures of celestial objects.
B) Measuring the positions of stars.
C) Taking pictures of celestial objects.
D) Studying the chemical composition of stars.

A) To prevent the telescope from drifting.
B) To measure the speed of stars.
C) To find the North Star.
D) To accurately align an equatorial mount.

A) Light pollution filter.
B) Solar filter.
C) Moon filter.
D) Hydrogen-alpha filter.