It is called image to a representation or the appearance of something. The concept is often used to refer to the reproduction of an element that arises when the light rays that come from it combine.
Satellite , on the other hand, is that linked to the satellites artificial . This is called space vehicles that are located in orbit around our planet or another star and are equipped with machines to receive and transmit information.
From these definitions we can understand what a satelital image . It's about the visual representation of that information which is registered by an artificial satellite.
These satellites have sensors which allow them to collect information that reflects the earth's surface. Once they receive the data, they send it back to the land , where they are processed.
On August 14, 1959, the satellite called Explorer 6 , belonging to the government of North America, obtained the first satellite image of our planet. A few months later, on October 6, the Soviet satellite Moon 3 He made the first capture of the Moon while he was on a mission that aimed to take pictures of his side hidden.
In this context it is necessary to talk about The blue marble , the name that receives a satellite image of the Earth that the ship's crew Apollo 17 he captured on December 7, 1972. This photograph, which went down in history, was taken about 29,000 kilometers from distance of our planet. His fame is so great that few images of the Earth have been used as many times as this.
The official name that NASA gave to this satellite image is AS17-148-22727 and the Apollo 17 astronauts performed it while they were traveling to the Moon. In it we can appreciate the space between Antarctica and the Mediterranean Sea coast. It is important to note that the Apollo had never been able to take a photograph of the ice cap pole south, although in the image the clouds cover it almost completely.
Another highlight of this satellite image is that it shows the coast of Africa almost entirely and with a good percentage of visibility. Also present are Madagascar (the largest island of this continent), the Arabian Peninsula (of great relevance in the gulf war of 1990, in addition to connecting Africa and Asia), and the region Austral of the Asian continent at the top of the photograph.
On July 23, 1972, the United States put in orbit the first satellite of a line called Landsat, which were built with the purpose of obtaining satellite images of our planet in high resolution. Since then they have launched several, and they are recognized by a serial number at the end of their name: until February 2013 there were eight, although by 2011 the first five were out of service.
The orbit that Landsat makes around our planet is of type heliosynchronous circular. They are 705 kilometers high, their inclination with respect to Ecuador is 98.2 degrees and their period is 99 minutes. His step of hemisphere North to South always takes place between 10:00 a.m. and 10:15 a.m.
Satellite images are used in multiple fields. Have these types of photographs of the land It is very useful for mapping , for example. They are also used to study the weather , forecast atmospheric phenomena and develop geographic information systems.
The meteorological satellites , to cite a specific case, orbit some 35,000 kilometers high , taking images every one, two or three hours of different points of the planet . When traveling at the same speed as the rotation of the land , each one allows you to always observe the same area.