Wednesday, December 7, 2011

Putting it in perspective

I went to a pub quiz last night and the first question that was asked was how much was a light-year in miles.  A light-year, for those uninitiated, is the distance light travels in a year.

The three choices were:
  • approximately 6 million miles
  • approximately 6 billion miles
  • approximately 6 trillion miles
..and the answer was (drum roll):  6 trillion miles.

To put that in perspective, a single beam of light takes, on average, about 8 minutes to travel from the Sun to the Earth. For the closest galaxy from us, light takes about 1.4 million years to travel to Earth or about 8.6 million trillion miles.

The time it takes a passenger plane to travel from Sydney to Los Angeles (7497.06 miles) is about 13 hours.  If that passenger plane were to try and travel the equivalent distance to the Sun, it would take about 18 years.  To the closest neighboring galaxy, it would take about 1.7 trillion years.

Certainly puts things in perspective, doesn't it?