Sunday, August 26, 2012

Bon Voyage Neil Armstrong

The first man to walk on the moon has passed on to his next great journey. Neil Armstrong passed away yesterday at the age of 82 due to complications with coronary surgery. Not only was Mr. Armstrong the first man to step onto the moon's surface, but it was he was the lunar module's (LEM's) pilot, who took over control of the LEM's automatic landing program during the final approach in order to avoid a field of car-sized boulders and thus avoid the first extra-terrestrial space disaster.

Before joining the space program, he was a test pilot. He was also an engineer. He was one of the few pilots to fly the X-15. After joining the space program, he flew on the Gemini 8 mission, rendezvousing and docking (another first) with an Agena booster in low earth orbit. He was an exemplary pilot with nerves of steel, but in person a retiring person, averse to being in the spotlight. Fame did not suit him.

Like so many others, I would've liked to have met him. But who wouldn't? I have met a few of the Apollo astronauts in passing. But there are fewer and fewer left these days. Eight of the original twelve moonwalkers are still with us, but they are all in their 80s. The time may come when no-one on Earth will be left who has been on the moon, or any other celestial body for that matter. If that time comes, who will inspire our kids to be the next bunch of explorers to inspire future generations?

Farewell Mr. Armstrong. Godspeed wherever you have gone.

Wednesday, August 08, 2012

Mars Science Laboratory is a "Curiosity" on Mars

I'm sure any potential Martians were quite surprised when the car-sized "Curiosity" rover (a. k. a. Mars Science Laboratory) landed on Mars. Congratulations to JPL for an extraordinary job well done. The picture above was taken by the still functioning Mars Reconnaissance Orbiter as Curiosity descended under parachute. I don't know what is more remarkable -- that one Mars mission took pictures of another Mars mission's arrival or that Curiosity landed in one piece.
At first glance, the proposed landing technique for the rover seemed insane. Its supposed to work this way: The rover and all of its landing paraphernalia enters the Martian atmosphere behind its heat shield at very high speed. After the heat shield has done its job and the rover has slowed down enough, the heat shield is ejected and the main parachute is deployed (see picture above). (NOTE: Since the martian atmosphere is quite thin, parachutes don't provide the same braking power as we Earth-dwellers enjoy. In the case of Curiosity, its speed was reduced from Mach 2.2 (about 1400 mph) to about 220 mph. This is why Mars landing craft need rocket breaking to land on Mars in one piece.) Somewhere in the process "floating" down towards the martian surface by parachute the rover prepares its wheels and such for surface operations and then lowers itself several meters by cable to end up suspended below a rocket powered platform. This is called the "sky crane" configuration. In the last few seconds, the rockets on the platform fire and bring the rover to a gentle stop on the Martian surface. At about the same time as the rover touches down, the cables holding the rover to the rocket platform are cut and the rocket platform flies off somewhere other than on top of the Curiosity rover. A better explanation for this process can be found here. So congratulations to NASA and to the engineer who came up with this bold landing plan!

Congrats to SpaceX for Successful Dragon ISS Meet-up.

This post is long overdue, but I feel that I must at least say something. On May 31st, the first commercial flight to ISS concluded with a successful splash landing into the Pacific Ocean off of Baja California. The capsule was successfully recovered. This event topped off a flawless first flight to ISS. More images from the flight are available at the SpaceX website, particularly in the section of the website devoted to the Dragon Spacecraft. According to the SpaceX launch manifest, Dragon will run resupply missions to ISS 11 more times between now and the end of 2015. One side comment. Is it just me, or does the Dragon look just like a giant toasted marshmallow in the recovery pictures?