Aristarchus’ only extant treatise is “On the Sizes and Distances of the Sun and Moon.” In it he calculated the diameter of the Sun as about seven times the diameter of the Earth, thus estimating the Sun’s volume as about 300 times the volume of the Earth
Answer: Senator Stephen Douglas proposed the bill that became the Kansas-Nebraska Act as a way of getting southern support for Nebraska statehood. Douglas was seeking to bring Nebraska into the Union in order to bring those lands under government authority and lay the groundwork for building a Midwestern route of transcontinental railroad that would run to Chicago and benefit his state (Illinois). The compromise to gain support from the South was to create two states, Nebraska and Kansas, and allow voters in those areas to choose whether they'd be slave or free. The thought was that Kansas might end up as a slave state and Nebraska as a free state, thus maintaining the balance between free and slave states.
Further detail:
The Kansas-Nebraska Act was enacted by Congress in 1854. It granted popular sovereignty to the people in the Kansas and Nebraska territories, letting them decide whether they'd allow slavery. In essence, this made the Kansas-Nebraska act a repeal of the Missouri Compromise of 1820, which had said there would be no slavery north of latitude 36°30´ except for Missouri.
After the passage of the Kansas-Nebraska Act, pro-slavery and anti-slavery settlers rushed into Kansas to try to sway the outcome of the issue, and violence between the two sides occurred. The term "bleeding Kansas" was used because of the bloodshed. Kansas and Nebraska ended up as free states, but the Kansas-Nebraska Act had allowed the possibility that slavery could become slave states.
The Ottoman wars in Europe were a series of military conflicts between the Ottoman Empire and various European states dating from the Late Middle Ages up through the early 20th century.
But I would tell about the main one which change the face of Europe.
1453 — fall of Constantinople that was a great start to conquer Europe.
The attackers were commanded by the Sultan Mehmed II, who defeated an army commanded by Emperor Constantine XI Palaiologos and took control of the imperial capital, ending a 53-day siege that began on 6 April 1453.
She was arrested for casting an illegal vote