History of Astronomy

Aristotle

384 BCE

384-322 B.C He proved that the earth was spherical, he claims that the sun, moon, the planets, and the stars travel in seperate spheres that rotates around earth, and believed earth was the center of the universe.

Hipparchus

190 BCE

190-120 B.C he was the founder of trigonometry, he calculated the length of a year, calculated the distance from the earth to the moon, he also came up with the first catalog for the stars.

Ptolemy

100

100-170 A.D he believed that the earth was the center of the universe and he created the geocentric model, or the Ptolemaic system, is a description of the universe with earth at the center, he also wrote a book called almagest.

Copernicus

1473

1473-1543 he was a renaissance mathematician and astronomer, who formed a model of the universe but the sun is in the center, rather than earth, called the Heliocentric model.
helio = sun; centric =center

Tycho Brahe

1546

1546-1601 he was known his accurate and comprehensive astronomical instruments and planetary observations. He also recorded enough data on the motion of the sun, planets, and moon relative to the fixed stars to within 1 arc minute..

Galileo

1564

1564-1642 he was an Italian polymath and astronomer who used a newly invented telescope to discover the 4 main moons circling Jupiter Io, Europa, Ganymede, Callisto and to study sunspots of the sun and stars are not attached to a sphere around earth.

Hans Lippershey

1570

1570-1619 he was a German-dutch spectacle maker who was known for using the lens to invent the telescope. 3 x magnification

Johannes Kepler

1571

1571-1630 he was a German mathematician, astronomer, and astrologer. He discovered three major laws of planetary motion and elliptical orbit. Brahe’s assistant.

Refracting Telescope

1608

1608 it was a telescope that uses a converging lens to collect light. It was different from the reflecting telescope because it collects light rather than reflecting it.

Giovanni Cassini

1625

1625-1712 he was an Italian mathematician, astronomer, and engineer and he discovered the division of rings in Saturn.

Sir Isaac Newton

1642

1642-1727 he was an English mathematician and physicist who invented the reflecting telescope in 1668, formed the law of gravity, and laws of motion. He was also the first person to explain tides scientifically.

Reflecting Telescope

1668

1668 it was a telescope that uses a single or combination of curved mirrors that reflect light and form an image. It is different from a Refracting telescope because it reflects light rather than collecting it.

William Herschel

1738

1738-1822 he was an astronomer who discovered the infrared region of the electromagnetic spectrum and he figured that he can bend light to make colors. He was also the founder of the sidereal astronomy. He also discovered Uranus and its moons as well as 2 more of Saturn's moons also several comets including the periodic comet.

Percival Lowell

1855

1855-1916 he was an american astronomer who predicted the existence of a planet beyond the orbit of Neptune and started a search for this planet and was successful with the discovery of Pluto.

Ejnar Hertzsprung

1873

1873-1967 he was a chemist and astronomer who invented a graphical tool that astronomers use to classify stars and created the HR diagram that categorized stars by their color and brightness.

Albert Einstein

1879

1879-1955 he was a German physicist whose work helped astronomers study everything from gravitational waves to mercury’s orbit. He also made the theory of Relativity.

Edwin Hubble

1889

1889-1853 he was an american astronomer and discovered a spiral nebula and proved the existence of other galaxies other than the milky way. A telescope was also named by Hubble. Came up with big bang theory of how the universe began.

Karl Jansky

1905

1905-1950 he was an american physicist and radio engineer who discovered radio waves emanating from the milky way.

John Glenn

1921

1921-2016 he was a U.S marine Corps aviator, engineer, astronaut, and U.S senator of Ohio. He became the first american to orbit earth in 1962.

Neil Armstrong

1930

1930-2012 he was an american astronaut engineer and the first person to walk on the moon on space mission Apollo 11.

Yuri Gagarin

1934

1934-1968 he was a soviet pilot and cosmonaut. He was the first human to go to outer space when his vostok spacecraft completed its orbit around earth.

Sputnik

1957

1957 it was the world's first artificial satellite launched by the soviet union which means the U.S was losing the space race. it was the size of a beach ball and weighed 183.9 lbs and took 96 minutes to orbit the earth on its elliptical path.

Apollo Missions

1963

1963-1972 the Apollo Program was to successfully land humans on the moon and bring them back safely. Only 6 of these missions achieved this goal, 11, 12, 14, 15, 16, and 17.

The First Space Shuttle Flight

1981

1981 it was the fourth human spaceflight program carried out by the National Aeronautics and space administration which accomplished transportation for earth to orbit crew and cargo from 1981-2011

Mars Pathfinder

1997

1997 is an American robotic spacecraft that landed a base station with a roving probe on mars. This mission was the first of a series of missions to mars that were taken by rovers and was the first successful lander since the two vikings landed in 1976.

Cassini Orbiter

2004

2004 it was a collaboration between NASA, the European space agency, and the italian space agency to send a probe to study the planet saturn and its system. The orbiter was named after Jean-Dominique Cassini who discovered the Saturnian satellites Lapetus, Rhea, Tethys, and Dione in 1675.

SpaceX Falcon Heavy

2018

2018 it is a reusable heavy-lifting launch vehicle designed and manufactured by Space X