Space roses, Cosmic Reindeer, Arctic space pendants, and more! ASTEROID FLYBY: Approaching from the direction of the sun, mountain-sized asteroid 2015 JO25 will fly past Earth on April 19th approximately 1.8 million km away. NASA says there is no danger of a collision. This unusually bright space rock is about twice as reflective as the Moon.
Broadcast Antennas. Radio and television broadcast stations transmit their signals via RF electromagnetic waves. Broadcast stations transmit at various RF frequencies, depending on the channel, ranging from about 550 kHz for AM radio up to about 800 MHz for some UHF television stations.
The RF part of the spectrum is usually defined as being between 30 kHz and 300 GHz. RF radiation is mainly used in telecommunications. Mobile phones employ frequencies in the range of 800 MHz to 2GHz. Other uses of RF energy include microwave ovens and medical treatments.