This Sunday, the 5th of August, at 2231 Pacific Daylight Time, the Curiosity rover is scheduled to land on the surface of Mars. The red planet, on average, is about 158 million miles away. That creates an interesting communication problem we don't experience here on terra firma. A radio signal--traveling at 186,000 miles per second--can circumnavigate the earth a little more than seven times in one second. The earth's circumference is about 25,000 miles, and geostationary satellites orbit at just short of that distance, or about 22,000 miles. Thus we earth-bound mortals do not notice any significant delay when we use phones or TVs. Rather, what I should say, is that any delay we do experience is not due to the speed of light. Even those large distances are nothing to an electromagnetic wave. But Mars is another story. Divide 158 million by 186,000 and you get 850 seconds, or about fourteen minutes. That's how long it will take a message from Curiosity to reach the army of scientists, engineers, technicians, and the rest of the people at NASA and the Jet Propulsion Laboratory. When the spacecraft descends from orbit into the Martian atmosphere, it will take about seven minutes for all the stages to be completed and the rover to be set upon the surface. That means it will be seven additional minutes before they will know if everything was OK at the start of the descent. Add another fourteen minutes before anyone will know if the landing worked and Curiosity is intact and able to complete its mission. And if they need to send a signal to make a correction or initiate a program, they won't know if it has been received for another 28 minutes.
What agony! After months of planning, preparation, construction, and testing, not to mention the almost two years of space flight required to get to our planetary neighbor, the radio delay has to be an exquisite kind of torture. The Mars Science Laboratory is an ambitious effort, being ten times larger than the other Mars rovers and requiring a more complex deployment procedure. Unmanned, robotic space exploration is far better for science than putting people up there. When you use humans you have to spend so much time and energy keeping them alive that very little actual work gets done. These missions, nonetheless, are daring, sophisticated enterprises that ought to inspire awe and excitement amongst the citizenry. Here's something Americans are doing together, with public entities and private enterprise collaborating and cooperating. It isn't about party politics, and all the various ways we can divide ourselves into tribes and holler at each other about words and symbols are mercifully absent. Instead, our fellow humans are reaching for the stars, daring to do mighty things that will benefit all of us regardless of nation or creed.
I think it's fantastic, and I hope they succeed brilliantly. Some day Americans will return to space to explore beyond earth orbit, adding the drama of actual astronauts out there risking their necks in pursuit of our collective dreams. Right now, though, the pathfinders are charting the course for us, showing us the hazards, and revealing the engineering solutions we need to make the possibilities real. The men and women at JPL may not leave their seats, or go too far from their computer screens, but they are sowing the seeds for a 21st century Magellan to reap. Here's to a homegrown Cook emerging in the next decade or two! I can't wait much longer than that, I want to be young enough to jump for joy when he or she makes it, unlike those great captains, all the way safely home.
It's all about the pitching - From ESPN:
4 days ago