Space Is the Place: A Galaxy of Far Out Words: Over The Moon: Planetary Vocabulary

Planets and their moons have complex relationships as they spin through space around the sun. These words describe their motions and relationships, and will help you understand the gravity of the situation.
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Full list of words from this list:

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  1. apogee
    the farthest point in an orbit around the Earth
    When the moon is far, it is at apogee.
    From the Greek apogaion, literally meaning "away from the Earth," apogee refers to the point in the moon's elliptical orbit that's farthest from the Earth.
  2. asteroid
    a small celestial body composed of rock and metal
    Last November Hayabuse2 finally left its orbit around the asteroid and began its one-year journey home.
    Aster is "star" in Greek, so an asteroid is a star-like object: a bright dot visible to the naked eye, but moving differently than the stars.
  3. atmosphere
    the envelope of gases surrounding any celestial body
    The presence of methane increases the amount of heat trapped in the atmosphere.
  4. axis
    the center around which something rotates
    This led to the recognition of regular changes in key astronomical parameters: the eccentricity of Earth’s orbit around the Sun, and the obliquity and precession of Earth’s rotational axis.
    Axis is Latin, and it's also the source of axle the rod around which a wheel rotates.
  5. crater
    a bowl-shaped geological formation at the top of a volcano
    The robotic explorer would be NASA’s fifth rover on Mars, and it is very similar to Curiosity, which is now exploring the Gale crater.
    In Ancient Greece, a crater was a bowl in which water and wine were mixed for drinking.
  6. eccentricity
    a circularity that deviates from a circular path
    This led to the recognition of regular changes in key astronomical parameters: the eccentricity of Earth’s orbit around the Sun, and the obliquity and precession of Earth’s rotational axis.
    An eccentric orbit is not circular. An eccentric person is odd, quirky, a little off-center.
  7. geocentric
    having the earth in the middle
    After all, the geocentric Ptolemaic theory of epicycles was mathematically appealing and its framework was broad enough to describe the motion of all planets on the sky.
  8. gibbous
    (used of the moon) more than half full
    It was the moon—a 93.6% waxing gibbous at time of writing.
    Gibbus means "bump" or "hump" in Latin, so a gibbous moon is one that's moving towards its full phase.
  9. heliocentric
    having the sun as or in the middle
    Based on Polish mathematician Nicolaus Copernicus’s model, this heliocentric description challenged the teaching that the Sun revolved around Earth.
  10. lunar
    of or relating to or associated with the moon
    “The prospect of deploying an advanced reactor to the lunar surface is as exciting as it is challenging.”
  11. meteor
    a mass that enters earth's atmosphere, becoming incandescent
    Often the gathering coincides with the Perseids, a spectacular meteor shower.
  12. orbit
    the path of a celestial body in its revolution about another
    In May 1962, Scott Carpenter became the second U.S. astronaut, after Glenn, to orbit Earth.
    Orbis means "spherical" in Latin; it's where we get orb from as well.
  13. perigee
    the nearest point in an orbit around the Earth
    The phenomenon happens when the celestial satellite reaches its closest point to Earth - known as a perigee - and is on the opposite side of Earth to the sun.
    The opposite of apogee, above.
  14. planetarium
    an apparatus or model for representing the solar systems
    If you’ve ever been to a planetarium, perhaps you remember seeing a vibrant representation of a night sky from the perspective of where you were sitting in that moment.
  15. pole
    either of the two endpoints of the Earth's axis of rotation
    He noted that E arth’s poles influence weather conditions far away, where hundreds of millions of people live.
  16. retrograde
    moving or directed or tending in a backward direction
    Jonathan Kaplan, a clinical psychologist in New York, recently noticed that more and more of his clients are referring to Mercury being in retrograde.
    Sometimes planets appear to move "backwards," that is in the opposite direction from their normal paths through the sky. It's just a function of the way the Earth's orbit and theirs line up sometimes. Retrograde can also be used to describe people, opinions, or legislation that are backwards or which seem intent on moving society in reverse.
  17. rotation
    the act of turning as if on an axis
    Litvinyuk is impressed by the measurements of the rotation of the clock hand.
  18. satellite
    any celestial body orbiting around a planet or star
    The pictures are the first released from the Solar Orbiter satellite mission, led by the European Space Agency.
  19. terrestrial
    of or relating to or characteristic of the planet Earth
    It was that the neutrinos were not making it to our terrestrial detectors—or rather they were changing en route.
  20. wax
    increase in phase
    Sunspot activity waxes and wanes, oscillating over an 11 year period.
    Wax is a Germanic word, and describes the moon growing larger each night as it becomes full.
  21. wane
    a gradual decline (in size or strength or power or number)
    In the following years, antitrust enforcement waxed or waned depending on the administration in office; but after 1980, it virtually disappeared.
    The opposite of wax: when the moon becomes thinner, moving towards new, or anything else that diminishes in intensity or force.
Created on Sun Aug 09 20:13:30 EDT 2020

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