Space Exploration and Astronomy

The International Space Station (ISS) is a habitable artificial satellite in low Earth orbit that has been continuously occupied since November 2000, serving as a microgravity research laboratory and home for international crews.

The Hubble Space Telescope was launched into low Earth orbit by the Space Shuttle Discovery on April 24, 1990, marking a major milestone in modern astronomy.

While the Hubble Space Telescope is indeed used to observe galaxies and planets, it was launched in 1990, not 1899. Spaceflight technology did not exist in the 19th century.

The International Space Station is a collaborative project involving five participating space agencies: NASA (United States), Roscosmos (Russia), ESA (Europe), JAXA (Japan), and CSA (Canada), representing 16 nations in total.

A natural satellite is any celestial body in space that orbits around a larger body. While the other options are artificial, man-made satellites, the Moon is Earth's only natural satellite.

Alan Shepard became the first American in space on May 5, 1961, during the Freedom 7 mission. John Glenn was the first American to orbit Earth (1962), while Neil Armstrong and Buzz Aldrin were the first humans to walk on the Moon (1969).

The Canadarm (and its successor, Canadarm2) is a famous robotic arm developed by Canada that has been used on Space Shuttle missions and the International Space Station to capture satellites and assist in maintenance. It is a celebrated symbol of Canadian technological achievement in space exploration.

Robotic vehicles designed to move across the surface of Mars are called Mars rovers, such as Curiosity and Perseverance. While landers also touch down on Mars, they remain stationary, whereas rovers are mobile vehicles.

The exosphere is the outermost layer of Earth's atmosphere, where the air is extremely thin. Many artificial satellites orbit Earth within this layer because there is very little atmospheric drag.

The Soviet Union's Luna 2 spacecraft successfully impacted the surface of the Moon on September 14, 1959, becoming the first human-made object to reach another celestial body.

In 1610, Galileo Galilei used his telescope to discover the four largest moons of Jupiter, now known as the Galilean moons (Io, Europa, Ganymede, and Callisto). This discovery provided critical evidence for the Copernican heliocentric model of the solar system.

While the telescope was invented in the Netherlands for terrestrial use, Galileo Galilei was the first person to systematically point it toward the night sky in 1609 to observe celestial bodies. Copernicus formulated the heliocentric theory before the telescope was invented, and sailors used spyglasses primarily for navigation.

Falcon 1 was SpaceX's first launch vehicle, a two-stage-to-orbit liquid-fueled rocket. It achieved orbit in September 2008 after several failed attempts, paving the way for the Falcon 9.

The Soviet Union launched Salyut 1, the world's first space station, in 1971.

Voyager 1, launched by NASA in 1977, became the first human-made object to cross the heliopause and enter interstellar space.