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384 BCE
Aristotle
Aristotle-(384 to 322 b.c.) He proved the Earth is a sphere and the center of the universe. He believed the sun, moon, planets, and stars travel in different spheres around the Earth. -
190 BCE
Hipparchus
Hipparchus-(190-120 b.c.) Founder of trigonometry. Discovered the procession of the equinoxes and solstices. Calculated the length of a year in 61/2 minutes. Calculate the distance of the Earth and moon. Came up with the first catalog of stars. -
100
Ptolemy
Believed the Earth was the center of the Earth geocentric/Ptolemaic. -
1473
copernicus
he formulated a model of the universe that placed the sun rather than the Earth in the center. -
1546
Tycho Brahe
He helped over turn the thinking and make them understand the heliocentric model of the universe. -
1564
galileo
He used his telescope to discover the four moons circling Jupiter, the moons are called Io, Europa, Ganymede, and Callisto. -
1570
Hans Lippershey
He invented the telescope. The magnification of the telescope is 3x. -
1571
Johannes Kepler
He discovered three major laws of planetary motion. He was Brahe’s assistant. He discovered that the orbit of the planets are not circular but elliptical. -
Giovanni Cassini
He discovered the Cassini division of the dark gap between the rings of Saturn. He also discovered four of Saturn’s moons. -
Sir Isaac Newton
Formulated the law of gravitation and discovered the law of motion. He also made the reflecting telescope. -
Reflecting Telescope
Uses a single or combination of curved mirrors that reflect light and form an image. -
William Herschel
He discovered the planet Uranus and its moons. He developed a theory of the stellar evolution. Herschel performed an experiment he used a prism and thermometers and he discovered the infrared region. -
Refracting Telescope
Uses a lens as its objective to form an image. The refracting telescope design was originally used in spy glasses and astronomical telescopes but is also used for long focus camera lenses. It’s different than a reflecting telescope because refracting is changing the direction of any wave, and reflecting is when waves bounce back and not absorbed. -
Percival Lowell
Discovered the planet Pluto and studied the “canalis” on Mars. Built the Lowell observatory in Flagstaff, AZ to study Mars. -
Wjnar Hertzberg
One of the inventors of the Hertzburg_Russell diagram. The HR diagram shows the correlation between the absolute magnitude (brightness) and the color of the stars. -
Albert Einstein
Theory of relativity and gravitation -
Edwin Hubble
Measures deflection of starlight by a foreground object -
Karl Jansky
He discovered radio waves coming from the Milky Way. He was considered one of the founding figures of radio astronomy. -
John Glenn
In 1962, he became the first American to orbit the Earth, circling it three times. -
Neil Armstrong
He is the first person to walk on the Moon. -
Yuri Gagarin
Russian cosmonaut Yuri Gagarin became the first human to travel into space when he launched into orbit on the Vostok 3KA-3 spacecraft. -
Sputnick
Sputnik was about the size of a basketball and weighed about 180 pounds. It was equipped with two radio transmitters and four long antennas that broadcasted a constant beep while circling the Earth for 21 days. It was the very first satellite to go into space, became a space race between the Russians and United States. -
Apollo Missions
The Apollo program was designed to land humans on the Moon and bring them safely back to Earth. Six of the missions Apollos 11, 12, 14, 15, 16, and 17 achieved this goal. Apollos 7 and 9 were Earth orbiting missions to test the Command and Lunar Modules, and did not return lunar data. -
First Space Shuttle Flight
Was the fourth human spaceflight program carried out by the National Aeronautics and Space Administration, which accomplished routine transportation for Earth to orbit crew and cargo, it took 30 years. -
Mars Pathfinder Expedition
It was designed as a demonstration of a new way to deliver the first-ever robotic rover to the surface Mars. It not only accomplished this goal but also returned with an amazing amount of data and outlived its primary design life. -
Cassini Orbiter
The spacecraft was launched with two elements, the Cassini orbiter and the Huygens probe. Cassini-Huygens reached Saturn and its moons. Huygens entered the murky atmosphere of Titan, Saturn's biggest moon, and descended by a parachute onto its surface, the most distant spacecraft landing to date. -
SpaceX Falcon Heavy
Falcon Heavy is a partially reusable heavy lift launch vehicle designed and manufactured by SpaceX. It is derived from the Falcon 9 vehicle and consists of a strengthened Falcon 9 first stage as a central core with two additional first stages strap on boosters.
