Date:         Fri, 3 Aug 2012 20:03:14 -0400
Reply-To:     frankgrun@AOL.COM
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Frank Grunthaner <frankgrun@AOL.COM>
Subject:      The Highly Anticipated (by some of us) Adventure of Curiosity
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Fellow Vanagonites and Wannabees,

With too many things on my plate, I have recently succumbed to lurking on the list until provoked to comment. Since my calendar has rolled to Friday, I'd like to offer a few comments about the fruition of 5 to 15 years of work by some of the most dedicated and intelligent people I know. As many of you know, the Mars Science Laboratory carried by the rover named Curiosity will attempt to land successfully on the surface of the planet Mars at about 10:30 PM PDT.

This landing as well as the design and construction of Curiosity is the singly most complex effort ever attempted by our species outside the surface of our planet earth. The chances for failure are depressingly high, as our Russian colleagues know all too painfully well. On the other hand, the engineers and scientists at JPL have done all they can to ensure the success of the landing. The most critical stage of the entire mission is what we term EDL for Entry, Descent and Landing. Because Curiosity is so large and massive, a completely new landing system has been devised. The Sky-Crane system is designed to bring the rover near the surface, hover, search for a landing area free of large ground hazards, move to the preferred landing area and then gently lower the rover to the surface by a tether link. After surface contact, the Sky Crane must disconnect from the rover and then fly away to a distant area to crash. This procedure has been designed to safely transfer the rover to the surface and to minimize any chemical contamination of the landing site. All of this procedure must be accomplished by on-board computers and robotic hardware with no chance of interaction with controllers on earth.

In addition to the final landing issues, the other major threat is that of entry. Interplanetary velocities must be scrubbed by first, the heat shield and then the parachute system. If you are interested in the issues or the engineering the JPL website has pleanty of detail. I'll only comment here that the major problem is how little we know about the upper atmosphere of Mars. Detailed computer models have been run to establish the engineering parameters, but their based on so few measurements.

On a positive note, I want to bring to everyone's attention and amazing application for the iPhone and iPad that was developed by some of our software engineers in our Section 317. This app will appear for other platforms in the future, but if you are running Apple System 5.1 on your iPhone, iPad or iTouch, with backside camera, you can enjoy it now. This free application is called Spacecraft 3D.

Quoting from the app description, Spacecraft 3D is "an augmented reality (AR) application that lets you learn about and interact with a variety of spacecraft that are used to explore our solar system, study Earth, and observe the universe. Using a printed AR Target and the camera on your mobile device, you can get up close with these robotic explorers, see how they move, and learn about the the engineering feats used to expand our knowledge and understanding of space". This is already longer than I intended, so let me say that you will be amazed! (I think!)

Searching for a tension relieving liquid,

Frank Grunthaner
Senior Research Scientist
in situ Planetary Exploration
Jet Propulsion Laboratory
California Institute of Technology
Pasadena, CA 91109