Visualizing Size and Scale

Visualizing Size and Scale

For this assignment, you may work in pairs. Use the following estimates:

The Milky Way galaxy's disc has a radius of about 100,000 light years (LY).

The Earth's diameter is about 12,700 kilometers

The Sun's diameter is about 1,392,000 kilometers

The Radius of the star VV Cephei is about 1800 times that of the sun

It will turn out to be useful to notice that 1.8 meters is about 6 feet, thus 1800 millimeters or 180 centimeters is 6 feet.

Use Wikipedia to find the distance between the Earth and Sun, and search for any other facts (there shouldn't be many of them) you might need. Use Google Calculator if you wish, for conversions, and arithmetic. Hint: as of this writing (the entry does change over time) you can use the "Orbit and rotation" section of http://en.wikipedia.org/wiki/Earth to find the average Earth-to-Sun distance.

Earth and Sun

How many times larger than Earth's diameter is the Sun's diameter? ______.
If we round this to the nearest 10, the Sun is roughly ______ times the diameter of the Earth.
If instead if want just a rough estimate, then rounding to the nearest 100, we can say the Sun is roughly ______ times bigger than the Earth in Diameter
After finding out how far the Earth and Sun are, give a rough round figure for how many times bigger than the Sun's diamater this distance is: "The distance from the Sun to the Earth is about ______ times the diameter of the Sun". Rounded to the nearest 10: ______. Rounded to the nearest 100: ______.

Solve on scratch paper first, show only your Final draft clean, clear solution steps below:

Sun and VV Cephei

If the Sun were 1 millimeter in diameter (a spec whose width is that of the smallest "metric system" notches on your ruler) then VV Cephei would be a sphere whose diameter is _____ meters or about _____ feet.
If the Sun were 1 centimeter (just under a half an inch, or about a small marble) in diameter then VV Cephei would be a sphere whose diameter is _____ meters or about _____ feet.

Solve on scratch paper first, show only your Final draft clean, clear solution steps below:

Now suppose we want to scale things so that the Earth is the size of that marble: the Earth is 1 centimeter in diameter. Use the "rounded to the nearest 100" figures for how many times bigger the Sun's diameter is than Earth's, and how many Suns-diameter's worth correspond to the Earth-to-Sun distance. To give the corresponding size or length for:

How big the Sun would be in meters? ______ In feet ______.
How far away in feet would this (model of) the Earth be from our model of the Sun? ______ feet (or ______ (fraction) of a mile) (include fractions)
How big would the diameter of VV Cephei be? about ______ feet or about ______ miles

Solve on scratch paper first, show only your Final draft clean, clear solution steps below:

Suppose finally that we shrink the Milky Way down to the size of the Earth. The Earth is roughly spherical while the Milky Way is roughly a flat disk so we need to clarify the meaning: suppose we shrunk our Galaxy, the Milky Way, down so the diameter of it's disk (namely 100,000 light years) would become instead the same as the diameter of the Earth (or that the radius of the flat disk of the Galaxy would be the length of Earth's radius). You may wish to type "1 light year in kilometers" into Google.
1. How about the sun? ______.
  Solve on scratch paper first, show only your Final draft clean, clear solution steps below: