Well, that depends on how you define satellite! One definition of the word satellite is a body that orbits a larger body. If you take this as the definition of satellite then the answer to our question is millions! This includes actual spacecraft, and any man-made debris that has been made during the past 30 years of space exploration.People call this debris "space junk". "Space junk" orbits at a speed of roughly 7.5 kilometers/second. That is close to 17,000 miles/hour! Think of the damage even a small speck of paint could do to the space shuttle if impact occurred at such high speeds ! Another definition of satellite is a manufactured vehicle intended to orbit the Earth. This definition makes our count much less because it includes only spacecraft and not debris that orbits the Earth. The Goddard Space Flight Center's lists 2,271 satellites currently in orbit. Russia has the most satellites currently in orbit, with 1,324 satellites, followed by the U.S. with 658.

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https://www.windows2universe.org/?page=/kids_space/sat.html

Information given by Thapa is valuable

Satellites have played a huge role in development of many technologies such as world mapping, GPS, etc. However, their applications are not limited as imaging devices only. They are whole a lot more than just imaging devices. Remote Sensing is one of the many innovations that were possible, thanks to these satellites roaming around the earth. In this article we will be discussing various applications of this technology called Remote Sensing. After reading these applications your view towards satellites is going to change. Following are some major areas in which remote sensing is useful:

• Agriculture
• Forestry
• Weather
• Biodiversity
• Many more (number is damn high, can’t list out all, these are main fields in which it is mostly used)