The Space Shuttle was a partially reusable low Earth orbital spacecraft system that was operated from 1981 to 2011 by the U. S. National Aeronautics and Space Administration (NASA) as part of the Space Shuttle program. Its official program name was Space Transportation System (STS), taken from a 1969 plan for a system of reusable spacecraft of which it was the only item funded for development. The first of four orbital test flights occurred in 1981, leading to operational flights beginning in 1982. In addition to the prototype whose completion was cancelled, five complete Shuttle systems were built and used on a total of 135 missions from 1981 to 2011, launched from the Kennedy Space Center (KSC) in Florida. Operational missions launched numerous satellites, interplanetary probes, and the Hubble Space Telescope (HST); conducted science experiments in orbit; and participated in construction and servicing of the International Space Station. The Shuttle fleet’s total mission time was 1322 days, 19 hours, 21 minutes and 23 seconds.
Dr. Porco further believes that Enceladus's orbit could have been much more eccentric in the past. The greater the eccentricity, the greater the tidal squeezing, and the resulting structural variations produce heat. In this case, the heat would have been saved inside the icy moon, melting some of the ice to replenish the liquid water sea. Dr. Porco continued to explain that "(T)he tidal flexing occurring now is not enough to account for all the heat presently coming out of Enceladus. One way out of this dilemma is to assume that some of the heat observed today was generated and stored internally in the past... (N)ow that the orbit's eccentricity has lessened, the heat emanating from the interior is a combination of heat produced today and in the past." The bottom line is that these two forces of Mother Nature have an amazing impact on the feeding activity of fish and using this information to your advantage will make you a more successful angler. Take a few minutes and learn some of the simple rules relating to the weather, the moon, and fishing as soon as you can if you want to catch more and bigger fish. The ring around the Earth eventually began to condense into blobs that then proceeded to merge and create a large and brightly glowing sphere--our primordial Moon. Our Moon would have appeared to be ten times larger than it does today in Earth's ancient sky--if anyone had been around to see it.