View Single Post
  #1  
Old 10-06-2013, 04:36 AM
skysurfer's Avatar
skysurfer
Dark sky rules !

skysurfer is offline
 
Join Date: Dec 2011
Location: 33S 150E (AU holiday)
Posts: 1,181
Fantasy: travel to 1AU from Rigel

You all know Rigel, the topleft bluish white star of Orion ? It is actually one of the brightest stars in the sky, not only as we see it.
Its power output is 100 000 times that of the Sun mainly in the UV part of the spectrum.
Well, let's travel to it.
When I calculate on the known data and travel with a spaceship (how long would it take to travel 700 light years ...) until 1AU from Rigel, the spaceship won't survive.
At that distance, Rigel appears an an inimaginably bright ball with an angular diameter of 35º with magnitude of -38 !
From 1AU from the Sun we receive about 1000W / m2 of energy, which means 1000* 100 000 = 100 MW/m2 which means that an average living room wall of 10m2 receives the entire output of a (large) coal or nuclear power station.
Or 10kW / cm2 ! This means *every square cm* receives the energy of several times of a welding arc !
So even when the spaceship is made of the highest meltable solid (carbon) it will vaporize.
Even at 10AU (Sun-Saturn) it is still 100W / cm2 (=1MW / m2) which heats your spaceship's hull to white heat.

When we are able to look back, the Sun would be a starlet of +12.5 barely visible with a 10cm telescope and its ball measures 0.045 milliarcseconds and our Earth 0.4 microarcseconds ! This requires a telescope with a mirror diameter of at least 250km to see our Earth as a very little sphere !

Looking at the sky it is completely different. the brightest star is obviously Rigel B which still shines @ -14.5 brighter than the Full Moon from us and only a few bright stars seen from Earth can be seen as relatively bright stars, such as the three belt stars which are about as bright as from here.

Just fun to imagine this.
Reply With Quote