Friday, December 17, 2004, 6:16pm
Friday, December 17, 2004, 6:16pm
Passing through the night some random building construction has reached the naked light bulb stage. Rough lighting hangs throughout the framework for the benefit of those who will be finishing the interior. Until the final lighting system is installed and tested, these bare bulbs will be the only source of light apart from whatever stray light the sun can offer during the bleak days of winter.
Past the new BU hockey arena there is no obvious evidence of a game about to take place. In the dark of the night the place is just another building.
Then past the Allston freight yards we make good time below a crescent moon with a local lunar sunrise just about where Buzz and Neil once walked upon Mare Tranquilitis (or the Sea of Tranquility) appearing in the form of an ocean of darker basalt. Seen from space the twilight zone from night to day – from dark side to illuminated side – is called the planet’s terminator, and because of how longer shadows better define a landing site, its best to put one’s landing craft down just to the sunlit side of a terminator.
Soon humanity may see a brand new and even more spectacular terrain in a way hardly imaginable. The Casini spacecraft in orbit around Saturn is about to release its Huygiens probe for a one-way trek to the surface of Titan, the largest of Saturn’s family of moons. Titan is one of the very last mysteries of the relatively nearby solar system. Shrouded in photochemical fog, the surface has only recently been mapped to any reasonable degree by infrared imagers and radar aboard the Casini mother ship. But even with this, we have no clear idea what waits on the surface – frozen ice? Sticky tar-like hydrocarbons? Earthlike oceans full of liquid methane? The possibilities will only be understood by streaking into the atmosphere behind a protective heat shield, then drifting from a parachute for 90 minutes or more while sending results including photographs back to Casini for relay back to Earth. If we’re really lucky the probe might even survive long enough to send back a few images from the surface.
The usual exodus begins to queue at West Natick. This signals the end to the faster part of my rail excursion – except perhaps the last two miles between Framingham and Ashland where these trains often climb back to full track speed before crossing the Sudbury River and running fast into town behind the old Telechron clock factory. Alongside Homer Avenue we approach Main Street, blowing by John Stone’s Inn at 65 MPH, holding this speed another two hundred meters until the Cherry Street signals where engineers throttle back and coast the final mile into Ashland Station.
The moon is still with us, though soon enough it will set in the west like all things above and outside our present world. The moon’s orbit is in the same direction as the spinning Earth, and after billions of years spiraling away from us, the month of its orbit is now far longer than the near-geosynchronous orbit just after its formation. Yes, there was once an age when all the phases of the moon could be seen without interruption all in one day as the moon slowly drifted through the sky huge enough to clearly see its growing collection of craters without a telescope.
In our own time, the moon rises and sets roughly fifty minutes later each day slowly waxing and waning and waxing and waning. But that is not how the story ends. In another five to ten billion years the moon will have finally drained off all the rotational energy it can from our spinning planet. Then the days on Earth will be 50 present-days long with the moon locked high above some terrestrial locality never to set again.
Nothing alive will be here to witness the occasion, since by then the sun will have long since bloated into its red giant stage to boil away the oceans if they are still here and re-melt the crust if the planet isn’t destroyed outright, leaving the Earth/Moon system frozen cinders loosely orbiting the dead and frozen core of Helios – the Sun – a white dwarf slowly cooling and fading into the unfathomable ages to come. By then the only remaining record of humanity with be those spacecraft we’ve hurled deeply into the cosmos with the foresight of Carl Sagen to include a snapshot of who we were.
