There are an estimated 100 million galaxies in the observable universe, with our Milky Way galaxy thought to have about 400 billion stars. There are also an estimated 100 billion planets in the Milky Way galaxy . The average distance between galaxies is thought to be about 3 million light years.
1. In 1839, Friedrich Georg Wilhelm Struve used a refracting telescope with a 2.6-inch lens to measure the parallax of the star Vega, becoming the first person to successfully determine the distance to a star other than the Sun. 2. The world's largest refracting telescope is the Yerkes Observatory's 40-inch refractor, which was completed in 1897. 3. In 1948, American astronomer Edwin Hubble used the 100-inch Hooker telescope at Mount Wilson Observatory to confirm that the Andromeda "nebula" was actually an external galaxy and not part of our own Milky Way galaxy. 4. The 200-inch Hale telescope at Palomar Observatory in California was the largest telescope in the world from its
The James Webb Space Telescope is the most powerful telescope that will be launched in 2021. It will be able to see objects that are billions of light years away and study the effects of black holes on the surrounding space.
Black holes are fascinating objects in the universe that are created when a star collapses. As matter falls into a black hole, it forms an accretion disk that can get so hot it emits X -rays. Black holes can be millions to billions times more massive than our sun and some are rotating so rapidly that they can fling matter out into space at high speeds.
Black holes are extremely dense objects with a gravitational pull so strong that not even light can escape them. They come in different sizes, from smallstellar-mass black holes to supermassive black holes , and are thought to be at the center of every large galaxy. When matter falls into a black hole, it heats up and emits a bright light.
The 1970s saw the invention of the first personal computer and the first microprocessor. The Apple II was the first personal computer, while the Intel 4004 was the first mass-produced micro processor. The first microprocessor-based personal computer was the Altair 8800, and the first personal computer with a graphical user interface was the Apple Macintosh.
The first electronic computer was developed in 1937, and the first commercial computer was released in 1951. The first personal computer was the Altair 8800, released in 1975, and the first Apple computer was the Apple I, released in 1976. The first IBM PC was released in 1981, and the first laptop computer was the TRS-80 Model 100, released in 1982.
The article covers the interesting history of Silicon Valley, from its origins in Italy to its modern-day status as a global hub for technology and innovation. It covers some key milestones along the way , such as the invention of the silicon transistor and the release of the first commercially available computer.