Astronomy Basics
Define Zenith.
The point on the celestial sphere opposite the direction of gravity; point directly above the observer.
Which planet has the thinnest atmosphere? Why?
Mercury. There is not much that makes up the atmosphere.
How many planets make up the outer planets?
4
Our solar system composes of how many planets?
8
Define Geocentric.
A perspective that Earth was the center of the Universe.
Define Celestial Sphere
The apparent sphere of the sky; a sphere of large radius centered on the observer; directions of objects in the sky can be denoted by their position on the celestial sphere.
How many planets make up the Inner planets and why?
4. because they are closer to the sun.
Which planet spins at a 90 degree axis?
Uranus
How far is earth from the sun?
3rd Planet from the sun (93 million miles)
The dark spot on Jupiter is described as what?
Gaseous storms.
Define a year.
The period of revolution of Earth around the Sun.
Which planet has the thickest atmosphere and why?
Venus. It has a an atmosphere mostly composed of Carbon Dioxide.
The biggest outer planet is...
Jupiter
Orion's spur or arm.
How many of the outer planets have rings?
4. Jupiter, Saturn, Uranus, and Saturn.
Define Ecliptic.
The apparent annual path of the Sun on the celestial sphere.
Of the Inner planets which of the planets is the biggest?
Earth
What is a common theme as far as atmospheric composition of the outer planets?
Mostly Hydrogen and Helium.
What is at the center of our solar system?
The Sun.
Define a super cluster.
A group of galaxies, which themselves compose of clusters.
Define Horizon in Astronomy.
A great circle on the celestial sphere 90° from the zenith; more popularly, the circle around us where the dome of the sky meets Earth.
Which of the Inner planets is the hottest?
Venus
Which planets make up the outer planets? include the dwarf planet.
Jupiter, Saturn, Uranus, Neptune, and Pluto
The Virgo cluster is a part of what super cluster?
The Laniakea Super Cluster.
What is the measurement of a Astronomical Unit (AU)?
93 Million Miles. The distance of Earth from the Sun.