Astronomy 101 -- Worksheet #1Introduction and MOTIONS OF THE SKY1) Astronomy is ______________________________________ .2) Science involves the _____________ and _____________ of natural phenomena.3) The scientific method involves _______________________, ____________________, and____________________________________ .4) Most of what astronomers knowabout the Universe is learned through analyzing_______________________.5) Our daily,monthly,and annual calendars are based on observations of the _____________and _____________.6) WE ARE MADE FROM 100% RECYCLED _____________.7) The Earth rotates around its North-South axis in the period of time which we call one________________.8) Because of the rotation of the Earth on its axis, we see the regular______________________________ of the Sun, Moon, and stars.9) The SOLAR day has a length of __________, and is defined as _________________________________________________.10) The SIDEREAL day has a length of __________, and is defined as _________________________________________________.11) The celestial sphere is defined as ________________________________________________________.12) The extension of the Earth’sequator onto the skyisknown as the___________________________________.-2-13) The celestial poles are ___________________________________________________.14) The star which is located closest to the North Celestial Pole is known as _______________.This star appears to be unique because ___________________________________.15) Astronomers locate stars on the skywith a coordinate system which is equivalent to specify-ing the latitude and longitude of each location. The longitude-likecoordinate for stars is knownas _______________________. The latitude-likecoordinate for stars is known as_______________________.16) Right Ascension is measured in units of __________. The zero-point for this scale is the____________________, or equivalently,where the Sun is on ____________________. Thevalues for the Right Ascension coordinate range from __________ to __________.17) Declination is measured in units of __________. The zero-point for this scale is the____________________________. The values for the Declination coordinate range from__________ to __________.18) Right Ascension and Declination are fixed on the __________.19) The Right Ascension and Declination coordinates are also known as_____________________ coordinates. These are the coordinates which are used on your starcharts.20) Because each observer has a unique viewofthe sky, itissometimes useful for astronomersto define observer-dependent coordinates. In this system, the point directly overhead for a givenobserver is known as the __________.21) The horizon is defined to be _______________________________________________.22) The altitude of a star is defined to be the __________________________________.23) The azimuth of a star is defined to be the ___________________________________.24) For manyobservers on the Earth, there are some stars which neverappear to rise or set.These stars are known as