“Our planet is a lonely speck in the great enveloping cosmic dark. In our obscurity – in all this vastness – there is no hint that help will come from elsewhere to save us from ourselves. It is up to us.” –Carl Sagan
Here on our planet, this is the one day that we take out of the year to stop and appreciate just how amazing the natural world really is, and how fortunate we are to have the Earth that we have. A wonderful but sad reminder of how fragile it is, and how quickly and easily we can affect it, comes through John Prine‘s great song,
Here on our planet, there are countless ways to celebrate what we have. But what if you weren’t here on Earth; what if you were a distant space traveler, headed towards our Solar System for the first time?
(Image credit: SKY-MAP / WikiSKY.)
You’d see a rather unspectacular, whitish star. It would appear bright only because you were close to it. Even from our nearest star, Alpha Centauri, the Sun would only be the 5th brightest star in the night sky. If you knew the proper techniques, you could tell that there were gas giant planets around it, and — if your tools were excellent — some smaller, inner rocky worlds, too.
But unless you journeyed into the Oort Cloud, and then in past the Kuiper Belt, only at this point would it be easy for you to see Earth.
(Image credit: NASA / JPL.)
And even then, from 6 billion kilometers (4 billion miles) away, we&…