Sometimes, on weeks with lots of bad news, it’s nice to stop and think about how we sent a space probe to Pluto.
This animation, made with the LORRI (Long Range Reconnaissance Imager) images, begins with a low-altitude look at the informally named Norgay Montes, flies northward over the boundary between informally named Sputnik Planum and Cthulhu Regio, turns, and drifts slowly east.
NASA initially referred to it as the Whale in reference to its overall shape. By 14 July 2015, the provisional name “Cthulhu” was being used by the New Horizons team. It was named after the fictional deity from the works of H. P. Lovecraft and others.
A video adapted from Randall Munroe’s Thing Explainer, where complex subjects are explained “using only drawings and a vocabulary of the 1,000 (or ‘ten hundred’) most common words.” I believe this all started with the XKCD cartoon Up Goer Five, “the only flying space car that’s taken anyone to another world.”
I love this part at the end of the video.
You can find Thing Explainer at book stores, or by using your computer to search the place where computers think together.
Margaret Hamilton oversaw the guidance software on the Apollo program. Thanks to sophisticated error-handling in that code, her engineering efforts prevented an abort of the Apollo 11 landing.
Three minutes before the Lunar lander reached the Moon’s surface, several computer alarms were triggered. The computer was overloaded with incoming data, because the rendezvous radar system (not necessary for landing) updated an involuntary counter in the computer, which stole cycles from the computer. Due to its robust architecture, the computer was able to keep running; the Apollo onboard flight software was developed using an asynchronous executive so that higher priority jobs (important for landing) could interrupt lower priority jobs.
This was on a 2 MHz machine with 1 MB of RAM. Even the term software engineering was coined by Hamilton, who also helped develop “concepts of asynchronous software, priority scheduling, end-to-end testing, and human-in-the-loop decision capability.”
A safe mantra to keep in mind with software is “all software has bugs,” which so often means “don’t expect too much.” Margaret Hamilton was instrumental in creating processes to ensure that software can systematically accommodate surprises and continue functioning as expected.
A fan of the space program, Kipp Teague, has uploaded a huge trove of Apollo mission photo scans onto Flickr. They’re organized into albums, but rather overwhelming as a collection, unless you want to just page through thousands of space photos (which, I mean, yeah why not?).
Digg has posted a smaller “best of” selection if you want to see just the highlights.
The video was directed by Erik Wernquist and the photography is credited to “NASA/JPL/University of Arizona/Goddard Space Flight Center Scientific Visualization Studio,” which kinda makes me want to track down the originalsources.