At least an additional 530 million people have genital herpes and 290 million women have human papillomavirus. STIs other than HIV resulted in 142,000 deaths in 2013. In the United States there were 19 million new cases of sexually transmitted infections in 2010. Historical documentation of STIs date back to at least the Ebers papyrus around 1550 BC and the Old Testament. There is often shame and stigma associated with these infections.
Since light has a speed of 186,000 miles per second (light can travel about 7 times around the entire earth in 1 second!), light travels about 5,865,696,000,000 miles in just one year. You can attach 9 more zeros to the end of this to get 1 billion light-years and another one for 10 billion light-years. The farthest that Hubble has seen so far is about 10-15 billion light-years away. The farthest area looked at is called the Hubble Deep Field. 1  Javascript must be enabled to use Cool Cosmos.
The visible spectrum of light includes all of the colors that can be detected by the human eye, and it only makes up a very small portion of the total electromagnetic spectrum, about 400nm to 700nm. Optical telescopes use polished mirrors or glass lenses to focus visible light as it comes in through the aperture. There are two main types of optical telescopes, reflectors and refractors. Reflecting telescopes tend to be much larger and use parabolic mirrors to focus light. Refracting telescopes use lenses to bend light as it passes throught them. These are limited by the size of the lenses, and therefore tend to be much smaller than reflectors. Radio telescopes are used to study much longer wavelengths than visible light. Often, radio telescopes use a dish to focus the radio waves onto the receiver. The receiver then sends the signal to be recorded for astronomers to study.