NASA have sent another spacecraft to Jupiter called Juno. It was launched on August 5, 2011 and arrived at Jupiter on July 4, 2016. NASA published some results from the Juno mission in March 2018. Several other missions have been planned to send spacecraft to Jupiter's moons Europa and Callisto. One called JIMO (Jupiter Icy Moons Orbiter) was cancelled in 2006 because it cost too much money.
Jupiter has 79 known moons. The four largest were seen by Galileo with his primitive telescope, and nine more can be seen from Earth with modern telescopes. The rest of the moons have been identified by spacecraft. The smallest moon (S/2003 J 12) is only one kilometre across. The largest, Ganymede, has a diameter of 5,262 kilometres. It is bigger than the planet Mercury. The other three Galilean moons are Io, Europa and Callisto. Because of the way they orbit Jupiter, gravity affects three of these moons greatly. The friction caused by the gravity of Europa and Ganymede pulling on Io makes it the most volcanic object in the Solar System. It has over 400 volcanoes, more than three times as many as Earth.
Jupiter's large gravity has had an effect on the Solar System. Jupiter protects the inner planets from comets by pulling them towards itself. Because of this, Jupiter has the most comet impacts in the Solar System.
Two groups of asteroids, called Trojan asteroids, have settled into Jupiter's orbit round the Sun. One group is called the "Trojans" and the other group is called the "Greeks". They go around the Sun at the same time as Jupiter.
Notes
King
A king is a man who rules a country, because of inheritance. A king usually comes to power when the previous monarch dies, who is usually a family member of his. Sometimes a person may become king due to the previous monarch's abdication, for example George VI. For most of history, most countries were ruled in this way, especially in Europe. Some countries, such as France, are no longer monarchies. Some, such as the United Kingdom, still have a royal family. In some countries, people chose a new king from other people to decide from.
The wife of a king is called a queen. A woman who becomes a ruler because of inheritance is also called a queen.
If a country has a king or a queen, that means it is a monarchy. A country which a king or queen rules is called a kingdom.
In the Muslim world a King would be known as Malik or Sultan.
Knowledge
Knowledge means the things which are true, as opposed to opinion. Information which is correct is knowledge. Knowledge can always be supported by evidence. If a statement is not supported by evidence, then it is not knowledge. The evidence makes it justified; .
Knowledge can refer to a theoretical or practical understanding of a subject. This was the point of Ryle's distinction between "knowing that" and "knowing how". It can be implicit (as with practical skill or expertise) or explicit (as with the theoretical understanding of a subject); it can be more or less formal or systematic. In philosophy, the study of knowledge is called epistemology. The philosopher Plato defined knowledge as "justified true belief". This definition is the subject of the Gettier problems.
All knowledge is a claim to be true, but the claim can be incorrect. The only claims (propositions) which are certainly true are circular, based on how we use words or terms. We can correctly claim that there are 360 degrees in a circle, since that is part of how circles are defined. The point of Aristotle's syllogism was to show that this kind of reasoning had a machine-like form:
But actually, in the real world, not all swans are white.
The most widely accepted way to find reliable knowledge is the scientific method. Yet one thing all philosophers of science agree is that scientific knowledge is just the best we can do at any one time. All scientific knowledge is provisional, not a claim of absolute truth.
Knowledge in religion is different in that it depends on faith, belief and the authority of religious leaders, not on evidence of a scientific or legal kind. There are differing views on whether religious statements should be regarded as knowledge.
In many expressions of Christianity, such as Catholicism and Anglicanism, knowledge is one of the seven gifts of the Holy Spirit.
In the Garden of Eden knowledge is the factor that made humans greedy and treacherous. But in the Book of Proverbs it states: 'to be wise you must first obey the LORD' (9:10).
In Islam, knowledge has great significance. "The All-Knowing" ("al-ʿAlīm") is one of the Names of God, reflecting distinct properties of God in Islam. The Qur'an asserts that knowledge comes from God () and various "hadith" encourage getting knowledge. Muhammad is reported to have said "Seek knowledge from the cradle to the grave" and "Verily the men of knowledge are the inheritors of the prophets". Islamic scholars, theologians and jurists are often given the title "alim", meaning 'knowledgeable'.
Kauai
Kauai (Kaua'i in Hawaiian) is the second oldest (after Ni'ihau) and fourth largest of the main Hawaiian Islands, in the United States. Known also as the "Garden Isle", Kaua'i lies 73 miles (117 kilometers) across the Kauai Channel, northwest of Honolulu on Oahu. It is of volcanic origin. The highest point on the island is Kawaikini. It is located above sea level. The wettest spot on Earth, with average rainfall of a year, is just east of Mount Waialeale. The high yearly rainfall has eroded deep valleys and canyons in the central mountain. The waterfalls that have been created by erosion in canyons are now popular tourist spots.
The city of Lihue, on the island's southeast side, is the seat of Kauai County. It has a population of around 6,500, and is the main city on the island. Waimea, which is located on the island's southwest side and the first capital of Kauai, was the first place visited by Englishexplorer Captain James Cook in 1778. It was also the first capital of Kauai. The city is at the head of one of the most beautiful canyons in the world, Waimea Canyon, whose gorge is 900 meters (3,000 feet) deep.
The island of Kauai was featured in Disney's 2002 animated feature film "Lilo & Stitch".
Kahoolawe
Kahoolawe is the smallest of the eight main volcanic islands of Hawaii. It is west of Maui and south of Lanai. It is roughly 11 miles long by across (). The highest point, Lua Makika, is above sea level. The island is dry because its low elevation does not cause much rain (orographic precipitation) to fall from the northeastern trade winds.
Kahoolawe was used as a gunfire and bombing target by the United States military during World War II. It was a defense training area by the United States Navy from around 1941 until May 1994. Popular opinion in the state against this practice brought the end to this use. Navy has since been trying to cleanup unexploded ordnance (bombs and explosive shells) from the island. Ordnance is still buried or lying on the ground. Other items have washed down gullies and still other unexploded ordnance is underwater offshore. In 1981, the entire island was included on the National Register of Historic Places.
The island is planned to be given back to the Hawaiian people. In 1993, the U.S. Congress passed a law that "recognized the cultural importance of the island, required the Navy to return the island to the State, and directed the Navy to do an unexploded ordnance (UXO) cleanup and environmental restoration" . The turnover officially occurred on November 11, 2003, but the cleanup has not yet been completed. The U.S. Navy was given $400 million and 10 years to complete the large cleanup task, but this work has gone much slower than planned.