Don't miss the special BONUS offer during our Beta-test period. The next 100 new Registered Users (from a unique IP address), to post at least five (5) piglix, will receive 1,000 extra sign-up points (eventually exchangeable for crypto-currency)!

* * * * *    Free Launch Promotions    * * * * *

  • Free Ads! if you are a small business with annual revenues of less than $1M - will place your ads free of charge for up to one year! ... read more

  • $2,000 in free prizes! is giving away ten (10) Meccano Erector sets, retail at $200 each, that build a motorized Ferris Wheel (or one of 22 other models) ... see details

Electromagnetic spectrum

The electromagnetic spectrum is the collective term for all known frequencies and their linked wavelengths of the known photons ( electromagnetic radiation ). The "electromagnetic spectrum" of an object has a different meaning, and is instead the characteristic distribution of electromagnetic radiation emitted or absorbed by that particular object.

The electromagnetic spectrum extends from below the low frequencies used for modern radio communication to gamma radiation at the short-wavelength (high-frequency) end, thereby covering wavelengths from thousands of kilometers down to a fraction of the size of an atom. Visible light lies toward the shorter end, with wavelengths from 400 to 700 nanometres. The limit for long wavelengths is the size of the universe itself, while it is thought that the short wavelength limit is in the vicinity of the Planck length. Until the middle of the 20th century it was believed by most physicists that this spectrum was infinite and continuous.

Nearly all types of electromagnetic radiation can be used for spectroscopy, to study and characterize matter. Other technological uses are described under electromagnetic radiation.

For most of history, visible light was the only known part of the electromagnetic spectrum. The ancient Greeks recognized that light traveled in straight lines and studied some of its properties, including reflection and refraction. The study of light continued, and during the 16th and 17th centuries conflicting theories regarded light as either a wave or a particle.



Don't forget! that as one of our early users, you are eligible to receive the 1,000 point bonus as soon as you have created five (5) acceptable piglix.