A Huge Cosmic Bubble of Gas and Dust

I was reviewing a MAT082 lecture note and I clicked the Astronomy Picture Of The Day hyperlink. The "Explanation" for the picture started as follows.

   "A cosmic bubble of gas and dust, RCW 79 has 
    grown to about 70 light-years in diameter."

Diameters... timely subject; therefore, let's look at NASA.gov:: RCW79.

Google.com:: define: light-year

A light-year approximates 5.88 trillion (5,880,000,000,000) miles. This number needs to be multiplied by 70 because the RCW79 cosmic bubble is 70 light-years in diameter. [Note: the .88 in 5.88 trillion represents 880 billion.]

   5.88 x 70 = 411.60

   70 light-years is 411.60 trillion miles.

   411.60 trillion is 411,600,000,000,000

   411,600,000,000,000 is 411.6 x 1012

   411.6 x 1012 is 411.6 x 10 x 10 x 10 x 10 x 10 x 10
                         x 10 x 10 x 10 x 10 x 10 x 10

   411.6 x 1012 is 4.116 x 1014

First returned Google hyperlink was to The Nine Planets Glossary at Arizona.edu.

A light-year is "the distance light travels in one year." The speed of light approximates 186,282 miles per second. One light-year is 63,239 AU, where AU is astronical unit (distance between earth and sun).

Wikipedia.org:: Speed of light

Creator: Gerald D. Thurman [gthurman@gmail.com]
Created: 15 April 2005

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An Approximation Observation

One of the definitions given by Google said a light-year was "approximately 5.8 trillion miles." The difference between 5.88 trillion and 5.8 trillion is .08 trillion which is 80 billion.

In some cases being off by plus-or-minus 80 billion is insignificant; however, in other cases, being off by one could cause problems.

The Friday, 15 April 2005, Arizona Republic had a short "News from home" article from Saginaw, Michigan, about a guy stuck with a bullet in his chest because it is only 5 millimeters away from his "aortal artery."

Google Search tells us 5 millimeters = 0.196850394 inch.

It is tough to save somebody when a bullet is two-tenths of an inch away from the body's main artery. [ view an inch]

From Speed of Light (SOL) To Slowing Light

To be completed.