When New Horizons Halted

As the New Horizons spacecraft flies by Pluto today, it is collecting and sending back to Earth data from its many sensors.  But this success almost didn't happen.

On Saturday, July 11, The Washington Post had an article about the crisis that occurred just a week earlier (July 4).

The story illustrates a couple of key ideas in decision making and risk management.

First, the loss of contact occurred because the spacecraft was programmed with a contingency plan: if something goes wrong, then go to safe mode: switch to the backup computer, turn off the main computer and other instruments, start a controlled spin to make navigation easier, and start transmitting on another frequency.  A contingency plan is a great way to manage risk.

Second, fixing this situation required the New Horizons operations team to manage an "issue," not a "risk," because the problem had already occurred (it was not a potential problem).

Finally, after diagnosing the problem and re-establishing contact with the spacecraft, the team had to make a key decision: whether to stick with the backup computer or switch back to the main computer (which had become overloaded, causing the crisis).  Here, they displayed some risk aversion (not surprising considering the one-shot chance to observe Pluto): they went back to the main computer because they "trusted [it], knew its quirks, had tested it repeatedly."

Congratulations to all of the engineers, scientists, and technicians who designed, built, and operate the New Horizons spacecraft!

Managing the Risk of Fireworks

The Fourth of July is a great opportunity to talk about risk management.  Setting off fireworks at home is a popular entertainment, but it is dangerous, as the press reminds us every year: http://www.washingtonpost.com/blogs/govbeat/wp/2015/07/03/here-are-photos-of-all-the-horrific-ways-fireworks-can-maim-or-kill-you/

After assessing the risk, how can one mitigate it?  Here are the basic approaches:  (1) avoiding the risk by abandoning the planned action or eliminating the root cause or the consequences, (2) reducing the likelihood of the root cause or decreasing its consequences by modifying the planned action or performing preventive measures, (3) transferring the risk to another organization, or (4) assuming (accepting) the risk without mitigating it.

How would these apply to fireworks at home?
1. Avoid the risk: don't do it.  Go to a fireworks show or watch one on TV or find something else to do.
2. Reduce the risk: stick to sparklers and party poppers and follow safety guidelines (like these from http://www.cpsc.gov/safety-education/safety-education-centers/fireworks/): keep fireworks away from brush and other substances that can burn, don't let children play with fireworks, keep a bucket of water handy to douse the fireworks or anything that catches fire.
3. Transfer the risk: hire a professional (or other trained expert) to do a fireworks show at your place, or let a neighbor run the show while you and your family watch from a safe distance.
4. Accept the risk: indulge in the tradition!

The relative desirability of these options depends upon how much you like fireworks and how much risk you're willing to accept.

Have a Happy Fourth of July!