Curious Inquires - A Quarantine Journal

It is the 4th day of the 2 week quarantine at JW Marriot Hotel in Singapore. We stay at the 20th floor of the hotel, in a room facing west. The view of the Sunset is one of the few positives of the quarantine. The second time we saw the sunset, we felt that it was somehow different from Texas' - the Sun sets earlier! Why? My curious inquiry to this and another trivia provided me some brain exercise.

Sunset - viewed from Quarantine room

Sunset and Latitude

A quick check of Sun set time today, June 27, Singapore time:

Singapore 7:14pm  - latitude 1.29 degree N

Dallas       7:39 pm (standard time) - latitude 32.78 degree N

Beijing      7:47pm  - latitude 39.91 degree N

Toronto     8:03pm (standard time) - latitude 43.65 degree N

Anchorage  - 10:41 pm (standard time) latitude 61.22 degree N

Thinking about it, the Sun is to the north of equator during summer in northern hemisphere, so the further north, the later the sun set. It makes sense.

Thinking about it a bit more -- how do we define Sunset or Sunrise ? 

This must be a question solved long time ago in astronomy. I thought about it purely as a mental exercise, before checking the literature. I would make a tangent plane - horizon - for any location on the earth, if the the Sun is on the other side of the plane to the earth, the Sun is up, it is day time, otherwise it is night time. The time the Sun touches the plane, it is Sunrise when Sun goes above horizon or Sunset when Sun goes below the horizon.

Of course, the Sunset, Sunrise time calculation was developed long time ago, in fact, there is a equation to do the calculation  - Sunrise Equation. 

Furthermore, near equator the sunset/sunrise time varies little in a year, so there is no need to institute daylight saving time. In fact Singapore abandoned daylight saving time in 1936 

Closet lights

A frivolous feature in the guest room is the closet light, that turned on when the door to the closet opens up, and turned off when the door closed. I would have paid no attention to this feature but light in the room's closet was on all the time since our 3rd day here even when the closet door was closed. This made the night time like dawn, disrupting my circadian rhythm, making my jet-lag worse!

The first night I noticed the malfunction, I pushed the closet door a little bit, and the light went off. But it went back on after a few minutes. Using a pillow against the door yielded similar outcome.

A examination of the switch and the door, I determined that the malfunction was due to slight deformation in the frame of the closet or in the door itself, which make the deflection of the switch just a little bit smaller. 

Two ways to solve the problem: 1) fix the door or the frame; 2) find a way to add the deflection to the switch when the door is closed. Option 1 would be a non trivial project. Option two is easier. What I did was to add a bandit to the switch, which just added a layer of material between the switch and the door. When the door is open, the light is on, when door is closed, the added layer compensates the lost deflection, the light is off.  Problem solved!  Hopefully I won't wake up in the middle of light due to the closet light again.

the switch to the closet light - in the horizontal beam to the right

light remained on when the door was closed

bandit fix!

the bandit fix worked

These brain exercises made me alert, helped to beat jet-lag, and made the quarantine less boring.