Archives for the 'calendars' Category
Sunrise Sunset Calendar
Published on 24 Jun 2007 at 9:50 pm.
1 Comment.
Filed under calendars, time.
Mary Jo, over at Fly Away Cafe, has posted about a Sunrise Sunset calendar web site. This web site will compute and display sunrise and sunset times for an entire month for a wide variety of locations. It also computes moonrise and moonset times, and it will even compute twilight. It computes […]
Read ‘Sunrise Sunset Calendar’
April Fools’ Day
Published on 1 Apr 2007 at 8:12 am.
1 Comment.
Filed under calendars.
Today is April 1. Since childhood, I remember this day as being a day of practical jokes. People would tell you something outrageous, and then if you believed it, they’d laugh and shout “April Fools!” Sometimes major newspapers will have a joke by making up crazy stories and printing them on the […]
Julian Days
Published on 26 Mar 2007 at 5:00 pm.
No Comments.
Filed under astronomy, calendars.
Last week, we were doing a laboratory exercise in my introductory astronomy class, and at one point the students plotted data. They were plotted magnitudes versus Julian days. Astronomers often use something called Julian days. Today, March 26, 2007, at 23:00 UT is Julian Day 2454186.467361. That is not to be confused […]
Year of the Pig
Published on 17 Feb 2007 at 2:45 pm.
4 Comments.
Filed under calendars.
Today is New Moon. That means that the Moon is most nearly between the Earth and the Sun, and can not be seen. For many people around the world, it marks the beginning of a month. The Moon goes through a cycle of phases in about every 29.5 days. This makes […]
The New Year
Published on 1 Jan 2007 at 12:06 am.
5 Comments.
Filed under calendars.
I had been planning on posting about how arbitrary it is to decide to mark time in orbits of the Sun. But, exactly how you compute that is tough, because there are different ways to compute the year. How do you define a complete orbit? Everything that you use for reference […]
Another time change
Published on 28 Oct 2006 at 1:27 pm.
8 Comments.
Filed under calendars, time.
Well, there’s another time change that is upon us. I always hate it when we have to change time. The idea goes all the way back to Benjamin Franklin, who proposed to the French that they adjust the time during the summer months. You see, due to the tilt of the Earth, the […]
Marking time in years
Published on 11 Oct 2006 at 11:10 am.
1 Comment.
Filed under Uncategorized, calendars.
“Well, another year has gone by.” You hear that a lot. What does it mean? Can’t you say that every day? What makes that day so special?Â
You go to the doctor and they ask how old you are. You say about 45. They say, “But according to your chart you are only 44.” (If they […]
