Ask the Chatbot Games & Quizzes History & Society Science & Tech Biographies Animals & Nature Geography & Travel Arts & Culture Money Videos
secular perturbation
Directory
References
Discover
cloning. First cloned cat. First cloned companion animal. CC (copy cat) female domestic shorthair cat (b. Dec. 22, 2001) photo Jan. 18, 2002. Cloned at Texas A&M Univ. College of Vet. Med. & Biomedical Sciences. Reproductive cloning genetics DNA cc cat
CC, The First Cloned Cat
Set of emoticon. Smile icon set.
What’s the Difference Between Emoji and Emoticons?
Lusitania sinking, illustration from The War of the Nations (New York), December 31, 1919. World War I, WWI. This image is one of three on the page. (See source file for the other two.)
7 of the World’s Deadliest Shipwrecks
Nero (Nero Claudius Caesar Augustus Germanicus) (ad 50-54) the fifth Roman emperor (ad 54-68), stepson and heir of the emperor Claudius.
Did Nero Really Fiddle as Rome Burned?
United States electoral college map showing number of electoral votes by state.
How Does the Electoral College Work?
Groups of depositors in front of the closed American Union Bank, New York City. April 26, 1932. Great Depression run on bank crowd
Causes of the Great Depression
The Colosseum, Rome, Italy. Giant amphitheatre built in Rome under the Flavian emperors. (ancient architecture; architectural ruins)
New Seven Wonders of the World

secular perturbation

astronomy

Learn about this topic in these articles:

Earth-Moon calculations

  • geocentric system
    In celestial mechanics: Examples of perturbations

    …time increases is called a secular perturbation. Superposed on the secular perturbation of the longitude of the node are periodic perturbations (periodically changing their direction), which are revealed by the fact that the rate of secular regression of the node is not constant in time. The Sun causes a secular…

    Read More