physical science

• Ferdinand Magellan and Juan Sebastian Elcano - given credit for circumnavigating the world and proving the earth is not flat
• pythagoras - started the idea of a spherical earth
• plato - educated his students on the sphericity of earth but made no justification
• aristotle - noted that there were stars in Egypt that could not be seen in the other parts of earth
• eratosthenes - estimated the circumference of earth
• eudoxus of cindus - considered the first astronomer to explain the retrograde motion of the planets in the sky
• mercury, venus, mars, jupiter, and saturn - the five other planets
• earth - motionless in the center of the universe
• five other planets - enclosed in four concentric circles
• sun and moon - enclosed in three concentric circles
• motionless stars - lay in the outermost sphere
• aristotle - somehow patterned his model from eudosux' model
• aristotle - believed that the earth was composed of four elements
• fire, water, earth, air - the four elements
• aristarchus of samas - greek astronomer who made the first attempt to create a heliocentric model, which places the sun at the center of the universe
• three assumptions - how many assumptions did aristarchus had
• 18 times - how many times did aristarchus calculated earth was away from the sun
• claudius ptolemaeus or ptolemy - assumed that the planets revolved on epicycles which moved around the deferent
• epicycles - what is the small spheres
• deferent - what is the large sphere
• eccentric - center of the deferent
• equant - a point closer to the orbit's center
• nicolaus copernicus - polish astronomer, revived the heliocentric model of aristarchus
• nicolaus copernicus - his model was published in 1543, right after his death since he believed that it is not yet ready to be published
• tycho brahe - danish astronomer who also made planetary observations
• tychonic system - earth was at the center and the sun and moon revolved around it, and all other planets orbited the sun
• geoheliocentric system - such model was a type of
• pleaides star cluster - is visble to the unaided eye
• pleiades star cluster - appearance of this star cluster in the sky marks the beginning of the Incas' new year
• constellations - across cultures, ancient civilizations saw different patterns and shapes in the
• ancient egyptians - associated the constellations to their god
• Orion with Osiris - god of death, rebirth, and afterlife
• venus - second brightest object in the night sky after the moon
• mayan culture - the position of venus was used as a basis in deciding whether to start a battle against another tribe
• lunar crates - using his telescope (8x magnification) Galileo confirmed that there were mountains on the moon
• November 1609 - Galileo constructed a 20x magnification telescope which helped him gather better lunar observations
• moons of jupiter - Galileo saw Jupiter accompanied by four seemingly fixed stars
• jupiter's moon - the fixed stars
• phases of venus - the variations of illumination observed on the planet venus
• pisa, italy - in 1610 where Galileo observed the difference of venus' illumination