A Man with One Clock

I am at the San Francisco airport waiting to catch my flight back to Salt Lake and thought my flight might actually leave on time. Why? I checked the monitor and it said my flight is on time. Then I logged into my e-mail and it told me my flight is delayed by 2 hours! I have a computer and am too lazy to go back and check the flight monitor again and so I logged onto the airline website and asked for a flight status. It says my flight is only 45 minutes delayed. So what is the correct answer? This reminds me of an old saying: "A man with one clock knows what time it is, a man with two isn't quite sure." In my case, I have 3 and none of them agree.

One of the problems with keeping travelers up-to-date with the latest information is that it is often wrong. An airline may see a delay about to happen and so they notify passengers. Then a pilot will work a miracle and arrive sooner than expected. The seemingly 2-hour delay gets shortened to 45 minutes.

A quick check of my e-mail between paragraphs and I have received a message indicating that my flight is now only 45-minutes delayed. I have 2 sources of information that agree. It will probably change again before I actually board the flight and so I don't put much stock into my departure time until it actually happens. Fortunately I have a really good book to read and don't mind hanging out at the airport too much. I would like to get in at a reasonable hour but a delay is not heartbreaking.

World Clocks

Several people from my office have been traveling all over the place because of conferences. It is always difficult to remember what time it is in the various timezones throughout the world. My watch can tell me the time for all timezones, which is helpful when I am doing a lot of traveling. However it is a little cumbersome because it uses 3-letter airport codes to indicate the timezone. For instance, LAX represents the pacific time zone. Most Americans know that SFO (San Francisco International Airport) and LAX (Los Angeles International Airport) are in the same timezone. But what about ANC (Anchorage International Airport) and HNL (Honolulu International Airport)? And what about daylight savings time?

In reality, it doesn't matter what the exact time is when you are trying to call one of your coworkers in Japan. What really matters is if the sun is up or if it is the middle of the night. The best tool for that is a world clock which shows a map of the world with night areas colored darker than day areas (as shown in the image above).

There are a number of free world clocks that work on Windows, but I wanted one on Linux because that is my primary system at work. Doing a quick search on one of the Ham radio sites (because Ham radio guys use world clocks to determine the best frequencies to use) led me to Sunclock. It is a free program that can be found at ftp://ftp.ac-grenoble.fr/ge/geosciences/sunclock.

The program comes as source code and so you have to compile it. There are some simple instructions that come with the download and most Linux users should be able to get it working with a minimum fuss. If you run Linux and do business all over the world, this application is indispensable.