Playing With Time


Do you enjoy the game of turning the clocks back before bedtime and getting an “extra hour” of sleep as Daylight Savings Time (DST) ends? According to my Fitbit, I actually got less sleep last night than usual.

There is not much more to say about Daylight Savings Time that I haven’t already said, so read up if you missed those earlier posts. But this month, I have heard more squawking about DST than in past years. I saw that there are actually items on ballots for this week’s elections about getting rid of DST in some states. Congress would need to act to allow states to change since federal law doesn’t permit it. Only two states don’t observe DST – Hawaii and Arizona (though the Navajo Nation, which cuts through part of Arizona, does).

Moving ahead with clocks in spring is the game that seems to cause more problems psychologically and physiologically with people and their internal clocks. Honestly, I’ve never really felt any effect with the spring or fall changes. Maybe my internal clock is already screwed up.

What would it be like if we didn’t change our clocks twice a year?

If we were on Standard Time all year – which is what is most often proposed – we would probably notice it most during the summer. Without summertime DST, on the longest day of the year (June 21), the sun would rise at 4:11 a.m. and would set at 8:10 p.m. That’s early sunlight through your bedroom window. You might get nostalgic with those old DST later sunsets during summer.

What if we were on Daylight Saving Time year-round? You would notice it more during the winter months. On the shortest day of the year (December 21), the sun wouldn’t rise until 8:54 a.m. and would set at 5:20 p.m.

Sunrise, Sunset

sunrise sunset

Being a bit of an insomniac, I often see the sunrise. I don’t live on the Atlantic coast, sso I don’t get to see those horizon sunsets that often.  I’m always awake for the sunset, which in my neighborhood sets at a not very distant mountain. It disappears from my view before the official time of sunset.  People west of that mountain still see the sun up for some time.  It is a relative thing in our perception, though not astronomically.

When is the earliest sunrise and latest sunset of the year? The exact date of earliest sunrise (and earliest sunset) varies with latitude.  Paradelle is at 40 degrees north latitude. Here, the earliest sunrise of the year was this morning (June 14) at 5:25 AM. I saw it a bit later rise above a mountain ridge to the east. (Paradelle is between two mountain ridges called First Mountain and Second Mountain.

Is the photo above a sunrise over First Mountain or a sunset at Second Mountain? They really look about the same.

The latest sunset of the year for me will fall on or near June 27. That is not to be confused with the longest day of the year  (the day containing the greatest amount of overall daylight) which is on the solstice on June 21.

The earliest sunrises come before the summer solstice because the day is more than 24 hours long at this time of the year. In the Southern Hemisphere, the earliest sunsets of the year come before the winter solstice for the same reason. How is that possible? The main reason is the inclination of the Earth’s rotational axis.  At the summer solstice next week, Earth is close to aphelion (farthest point from the sun) which lessens the effect. Conversely, at the December solstice, Earth is close to perihelion (closest point to the sun) which accentuates the effect.

You can ask your phone or your computer for when sunrise and sunset times are for your home.

The Green Flash

A green flash seen from Santa Cruz, CA (Wikimedia)

The green flash has nothing to do with the red Flash of comic books. They are an optical phenomena that sometimes occur just after sunset or right before sunrise.

With the right conditions, a distinct green spot is briefly visible for just a second or two above the upper rim of the Sun’s disk.  It may look like green ray shooting up from the sunset (or sunrise) point.

These green flashes occur because the Earth’s atmosphere can cause the light from the sun to separate out into different colors.

They can be seen with the naked eye looking at a very clear and very distant horizon. Looking at a location near an ocean improves your chances.

The time to view is at the last moment before the sun disappears below the horizon. Don’t look too soon because the sun can dazzle (and possibly damage!) your eyesight.

The flash doesn’t occur at every sunset or at every location. It is an atmospheric trick. I have yet to catch one, but I keep checking whenever I am near an ocean sunrise or sunset.