TELESCOPES

A telescope is an optical instrument that magnifies a distant object and makes it appear brighter. They are the most important tool of astronomy.

The first telescopes had two lenses at opposite ends of a tube. At the other end is the light-collecting lens, called the objective. To make them look sharp, you need another lens at the near end of the tube, called an eyepiece.

Galileo Galilei improved on the design, creating a less curved lens to have a magnification of 3 to 20. However, this telescope has a very narrow field of view, so you can't see the entire sky. Keppler improved the telescope by putting two positive lenses, thus making much more sky come. Everything looks the other way around, but it is not a problem for astronomers.

Telescopes that use only lenses are called refracting telescopes. However, refracting telescopes of any design have a problem: objects seen at the edge of the field appear to have colored fringes due to the different way the light is bent.

The power of the telescope is the amount that magnifies distant objects.

The ancient Greeks divided the circle into 360 degrees. One degree is divided into 60 arc minutes and one arc minute is divided into 60 arc seconds.

If you double the diameter of the objective lens or mirror, you double the resolution, ie you can resolve two stars that appear twice as close together.

SATELLITES

satellites are objects in orbit around a planet. They can be natural, like the moons, or artificial, created by humans and launched into space by rockets. Artificial satellites have multiple purposes, including GPS for location, communication such as telephony and the Internet, observing and photographing the Earth for meteorological and astronomical purposes, as well as transporting telescopes to study the universe. The Hubble Space Telescope is an important example of a satellite that has made crucial discoveries in astronomy after correcting initial technical problems. The satellites also house various tools and sensors that provide valuable information. Additionally, some satellites carry people, increasing public interest in space travel, and competition between nations during the Cold War is a prominent example of this.

In 1957, the Soviet Union launched the first satellite, called Sputnik, followed by the successful launch of Explorer 1 by the United States four months later. The Soviet Union successfully continued its space program, sending the first living thing into space, Laika, a dog, and then the first man, Yuri Gagarin. This led the United States to establish NASA in 1958 and increase funding to compete in the space race. The United States finally won the race in 1969 with the moon landing of Neil Armstrong and Buzz Aldrin on the Apollo 11 mission.

The Soviet Union excelled by launching the first woman into space, Valentina Tereshkova, in 1963, while the United States took until 1983 to send its first woman, Sally Ride. Since then, NASA has overcome gender bias and does not consider gender when selecting candidates for space missions.

SPACE AGENCIES IN OTHER COUNTRIES

It is true that the United States and Russia are not the only countries with space programs. Several European countries contribute to the European Space Agency (ESA), and there are space agencies in other countries such as Canada, India, Japan, and China.

The China National Space Administration (CNSA) has demonstrated major progress in space exploration, including the successful landing of a rocket on the far side of the Moon in 2019.

In addition, there has been international cooperation in space exploration, such as the construction and operation of the International Space Station (ISS), in which the United States, Russia, Europe, Canada, and Japan have worked together. The ISS is an artificial satellite that has been inhabited by astronauts from multiple countries at the same time.

Canada has made notable contributions to space technology, including the invention of the Canadarm, a robot used to deploy, maneuver, and capture payloads in space.

In the wizarding world, there have been covert interactions between some wizards and other space agencies, but not with NASA due to the segregation imposed by Rappaport's Law in 1790, which forbids interaction between magical people and No-Majs (Muggles) in the United States.

Transporting people and supplies to and from the International Space Station is a major undertaking, and Muggle astronomers use various tools and technologies to carry out their work of research and exploration in space.

SPACE SHUTTLES

In the early 1980s, NASA began the Space Transportation System program, using fully or partially reusable space shuttles. These artificial satellites launched numerous satellites, interplanetary probes, and the Hubble Space Telescope for scientific experiments in orbit and the construction of the International Space Station. However, there were two fatal space shuttle accidents, and the program ended in 2011. Since then, the United States has relied on the Russian Soyuz spacecraft to transport astronauts and supplies to and from the International Space Station. The United States has new programs in development that have their first flights scheduled in 2019 and 2020, and one of them achieved its first unmanned flight and supplied the International Space Station on March 3, 2019.

RADAR

Radar is a detection system that uses radio waves or microwaves to determine the range, angle, or speed of objects. Although it was invented for military purposes, it is also used in air and ground traffic control, locating landmarks and ships at sea, weather tracking, geological observations, and radar astronomy. Astronomers have studied various astronomical objects using radar to gain information about their surface and their influence on magic.

ROVERS

Rovers are vehicles designed to explore the surface of planets or moons. Some carry people, while others are autonomous robots or controlled from Earth. Rovers take pictures, collect data and samples to study the planet or moon they land on. Until now, rovers have been sent to the Moon and Mars, mainly by the United States and Russia. America's Curiosity rover is searching for evidence of life on Mars. Driving a rover from Earth can be impractical due to the time lag in communication, which is why many rovers in faraway places, such as Mars, are autonomous.