A Year Along The Geostationary Orbit

Here is a cool video of a year through the distant eyes of meteorological satellite Himawari-8, from December 21, 2015 to December 21, 2016. The satellite observes Earth in geostationary orbit at 140.7 degrees East following Earth’s rotation by travelling at approximately 11068 km per hour at a distance from Earth at 35768 km. Check it out and look for the March 9, 2016 total solar eclipse!

COVID-19 Layer in Google Maps

According to Google Maps Help, there is a COVID-19 layer that you can turn on in the Google Maps app on your phone. It displays the 7 day average for the number of new cases per 100,000 people. It also indicates whether cases are increasing or decreasing. More info on the Google blog.

I updated Google Maps on my phone, but it was not there in the layer list. I found this on a Google Maps Help page that new features are rolled out in stages and you might not get it right away. Perhaps it is working for you? Add a comment if you got it to work along with type of cell phone and carrier you have.

UPDATE 9/29/2020 – The COVID-19 layer magically appeared in Google Maps on my Android phone. Looks like the info is at the county level.

The First Published View of Los Angeles

In March 1853, Congress appropriated $150,000 to survey proposed routes for a transcontinental railroad. The United States Army’s Corps of Topographical Engineers embarked on the work. There were five surveys conducted. One went from St. Paul, Minnesota to Puget Sound, where Seattle was later founded. Another traveled from St. Louis to San Francisco. A third started in what became Oklahoma and headed for San Pedro south of Los Angeles. Then, there was a route from Texas to San Diego. Finally, there was a survey that traveled the Pacific coast from San Diego to Puget Sound.

Between 1856 and 1861, eleven large volumes of published reports from the surveys were issued by the federal government. They included Continue reading

Say Bye Bye to US Survey Foot

I remember 30 years ago working on ESRI’s COGO software. If you ever used it back in the day, you were a hero creating a landbase from scratch with only measurements from tract and parcel maps and making sure everything closed well with your traverses.

One thing I found interesting was there were two definitions for measuring 1 foot. There was the international foot, which was defined as 1 inch = 2.54 centimeters exactly, or 1 foot = 0.3048 meters exactly. The other was the older US survey foot, which was defined as 39.37 inches = 1 meter exactly, or 1 foot = approximately 0.304800609601 meters, or multiplying US survey feet by the fraction 1200/3937 to get meters.

The US survey foot has been around since 1893 while the international foot was established in 1959 and is slightly more exact. One of the reasons we retained the US survey foot was because of our state plane coordinate systems, which were derived from the national geodetic control network, and are based on the relationship of 1 meter equaling 39.37 inches exactly. Fundamental survey units, such as rods, chains, statute miles, acres, sections, and townships, all depend on the relationship of 1 meter equaling 39.37 inches exactly.

Using two measurements for the same unit have been confusing over the years. But now the US survey foot will be obsolete by January 1, 2023. Click below to read more about it!

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