Home Alone

Most people who think about today, December 7th, will probably think about it as the 70th anniversary of the Japanese attack on Pearl Harbor that drove the United States into World War II. There is, however, another important thing that happened on this date 31 years after that ... but we'll get to that in a minute.

Two interesting things happened this week that give me cause for reflection. The first is that astronomers have discovered a planet, named Kepler 22-B, that seems to be the most earth-like planet yet found, located in the habitable ("Goldilocks") zone around its parent star, and with abundant surface water and an estimated surface temperature of about 72 degrees Fahrenheit. Scientists are still studying the data, but it looks as if we may have found a sister world capable of supporting life as we know it.

The second thing that happened this week is that NASA's Voyager 1 spacecraft has nearly reached the farthest edge of the solar system - 11 billion miles from the sun. It is the farthest any man-made object has traveled, and it is still - 34 years after its launch in 1977 - sending back information about its surroundings. Voyager will soon enter the so-called "stagnation zone," where the solar winds cast off by the sun are cancelled out by the interstellar winds coming from ... well ... out there.

In 1990, Voyager 1 took one of the most famous photographs ever taken. At the urging of the late astronomer Carl Sagan, mission controllers turned Voyager 1 around and snapped a photograph of earth from a distance of some 3.7 billion miles. This became the "Pale Blue Dot" photo which shows a tiny and insignificant Earth as a speck of pale blue against the black of the endless universe. This is the picture ... Earth is the speck about halfway along the brown band on the right side of the image:

Thirty-nine years ago today, astronauts on board the Apollo 17 moon mission took another famous photo of the earth from a distance of about 28,000 miles, which became known as the "Blue Marble" photo ...

This was the last full photograph ever taken of earth from space by a human being ... every similar photo since has been taken by an unmanned spacecraft.

These things coming together in the same week gives me pause for thought. It's humbling to think that everything we are, everything we have ever known, and everything that is yet to come, is taking place on this pale blue dot circling in the Goldilocks Zone of a very average star in a remote corner of a very average galaxy. We've found other planets that might be habitable, but they're so far away that we'll never visit them in our lifetimes, if ever. We've never seen an unambiguous indication that there is any other civilization out there. Star Trek may be the dream, but Kepler 22-B - 600 light-years away - is the reality. There may be life on Kepler 22-B, but since it would take us millions of years to get there, chances are we'll never know it.

Are we home alone? Is there anyone else out there marveling at their own Pale Blue Dot photo? Whether there is or there isn't, it's awesomely humbling.

It may not be a bad idea to think about the possibly one-of-a-kind nature of our Pale Blue Dot as we think about climate change, carbon footprints, greenhouse gases, pollution, and other bad stuff. This may not be a perfect world, but it's the only one we have. It's worth protecting.

Have a good day. More thoughts tomorrow.

Bilbo