ASTEROID, METEORS, AND COMETS 
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Asteroids are unlikely to be fragmented planets because (you may
choose more than one) 
   $a)      the total mass of asteroids is small
   $b)      no known mechanism exists to disrupt a planet
    c)      asteroid orbits are in the ecliptic
    d)      asteroids are typically only a few kilometers across
    e)      asteroids can have different colors

Comets could be (and were) proven to be beyond the Moon by observing
    a)      a collision of one with the Moon
    b)      the relative size of the comet tail and the Moon
    c)      a parallax larger than the Moon's
   $d)      a parallax smaller than the Moon's

Holga and Hilda are 2 asteroids. They have the same size and shape
and are at the same distance from Sun.  Holga is icy with an albedo of
0.9. Hilda is rocky with and albedo of 0.1.  Which is brighter in
visible light? 
   $a) Holga
    b) Hilda
    c) Both same
Which is brighter in infrared light?
    a) Holga
   $b) Hilda
    c) Both same

Long-period comets have orbits
    a)      the same as the orbits of short-period comets
    b)      that are circular
    c)      always in the ecliptic
   $d)      randomly oriented with respect to the ecliptic
    e)      of low eccentricity

The location of the Oort cloud of comets is
    a)      near Pluto's orbit
    b)      between the orbits of Mars and Jupiter
   $c)      between 1/6 to 1/2 the distance to the nearest star
    d)      close to the nearest star
    e)      we have no idea since it has never been detected

On a given day, one is likely to see the most meteors "shooting stars")
   $a) after midnight
    b) before midnight
    c) during the afternoon
    d) it doesn't depend on the time of day

The tail of a comet is generally directed
  $a)  away from the Sun because of the solar wind and radiation pressure
   b)  opposite the direction of motion as the comet passes through
interplanetary matter
   c)  toward the Sun because of the Sun's gravitational force
   d)  along the comet's magnetic field lines

Which of the following could cause a meteor shower?
   a) A meteoroid hits a cloud in the atmosphere, and creates a
thunderstorm.
  $b) Earth crosses the debris-filled orbit of a comet.
   c) Asteroids in the same orbit as the Earth.
   d) A small constellation of dying stars disintegrates.

An experiment is done in the Earth's upper atmosphere in which two kinds
of micrometeorites are collected:  cometary and asteroidal particles.
Which of the following statements is true about these particles?
[Optional hint:  If you drop a ball from a height of 5 feet, will
it strike the ground with a faster or slower velocity than a ball
dropped from a height of 20 feet?]
    a)  All particles have about the same velocity.
    b)  Asteroidal particles typically move faster.
   $c)  Cometary particles typically move faster.
    d)  These particles are all moving slower than Earth's escape velocity.
    e)  Two of the above.

Which of of Jupiter's major satellites probably suffers from the
highest velocity impacts? 
   $a)  Io. (Mass 9x10^22 kg, Distance 421,600 km)
    b)  Europa. (Mass 4.80x10^22 kg, Distance 670,900 km)
    c)  Ganymede. (Mass 1.48x10^23 kg, Distance 1,070,000 km)
    d)  Callisto. (Mass 1.08x10^23 kg, Distance 1,883,000 km)
    e)  All suffer the same impact velocities.