- Solar System (Wikipedia)
The Solar System is the gravitationally bound system of the Sun and the objects that orbit it. The largest of such objects are the eight planets, in order from the Sun: four terrestrial planets named Mercury, Venus, Earth and Mars, two gas giants named Jupiter and Saturn, and two ice giants named Uranus and Neptune. The terrestrial planets have a definite surface and are mostly made of rock and metal. The gas giants are mostly made of hydrogen and helium, while the ice giants are mostly made of ‘volatile’ substances such as water, ammonia, and methane. In some texts, these terrestrial and giant planets are called the inner Solar System and outer Solar System planets respectively.
- The Sun is the star at the center of the Solar System. It is a massive, hot ball of plasma, inflated and heated by energy produced by nuclear fusion reactions at its core. Part of this internal energy is emitted from its surface as light, ultraviolet, and infrared radiation, providing most of the energy for life on Earth.
- Alpha Centauri (Wikipedia)
Alpha Centauri (α Centauri, Alpha Cen, or α Cen) is a triple star system in the southern constellation of Centaurus. It consists of three stars: Rigil Kentaurus (Alpha Centauri A), Toliman (B) and Proxima Centauri (C). Proxima Centauri is the closest star to the Sun at 4.2465 light-years (1.3020 pc).
- Earth (Wikipedia)
Earth is the third planet from the Sun and the only place known in the universe where life has originated and found habitability. Earth is the only planet known to sustain liquid surface water, with ocean water extending over 70.8% of the planet, making it an ocean world. Most of all other water is retained in Earth’s polar regions, with large sheets of ice covering ocean and land, dwarfing Earth’s groundwater, lakes, rivers and atmospheric water. The other 29.2% of the Earth’s surface is land, consisting of continents and islands, and is widely covered by vegetation. Below the planet’s surface lies the crust, consisting of several slowly moving tectonic plates, which interact to produce mountain ranges, volcanoes, and earthquakes. Inside the Earth’s crust is a liquid outer core that generates the magnetosphere, deflecting most of the destructive solar winds and cosmic radiation.
- Jupiter (Wikipedia)
Jupiter is the fifth planet from the Sun and the largest in the Solar System. It is a gas giant with a mass more than two and a half times that of all the other planets in the Solar System combined, and slightly less than one one-thousandth the mass of the Sun. Jupiter is the third brightest natural object in the Earth’s night sky after the Moon and Venus, and it has been observed since prehistoric times. It was named after Jupiter, the chief deity of ancient Roman religion.
- Uranus (Wikipedia)
Uranus is the seventh planet from the Sun. Its name is a reference to the Greek god of the sky, Uranus (Caelus), who, according to Greek mythology, was the great-grandfather of Ares (Mars), grandfather of Zeus (Jupiter) and father of Cronus (Saturn). It has the third-largest planetary radius and fourth-largest planetary mass in the Solar System. Uranus is similar in composition to Neptune, and both have bulk chemical compositions which differ from that of the larger gas giants Jupiter and Saturn. For this reason, scientists often classify Uranus and Neptune as “ice giants” to distinguish them from the other giant planets.
- Gospel of Luke (Wikipedia)
The Gospel of Luke tells of the origins, birth, ministry, death, resurrection, and ascension of Jesus Christ. Together with the Acts of the Apostles, it makes up a two-volume work which scholars call Luke–Acts, accounting for 27.5% of the New Testament. The combined work divides the history of first-century Christianity into three stages, with the gospel making up the first two of these – the life of Jesus the Messiah from his birth to the beginning of his mission in the meeting with John the Baptist, followed by his ministry with events such as the Sermon on the Plain and its Beatitudes, and his Passion, death, and resurrection.
- Solar System (Wikipedia)
The Solar System is the gravitationally bound system of the Sun and the objects that orbit it. The largest of such objects are the eight planets, in order from the Sun: four terrestrial planets named Mercury, Venus, Earth and Mars, two gas giants named Jupiter and Saturn, and two ice giants named Uranus and Neptune. The terrestrial planets have a definite surface and are mostly made of rock and metal. The gas giants are mostly made of hydrogen and helium, while the ice giants are mostly made of ‘volatile’ substances such as water, ammonia, and methane. In some texts, these terrestrial and giant planets are called the inner Solar System and outer Solar System planets respectively.
- Milky Way (Wikipedia)
The Milky Way is the galaxy that includes the Solar System, with the name describing the galaxy’s appearance from Earth: a hazy band of light seen in the night sky formed from stars that cannot be individually distinguished by the naked eye. The term Milky Way is a translation of the Latin via lactea, from the Greek γαλαξίας κύκλος (galaxías kýklos), meaning “milky circle”. From Earth, the Milky Way appears as a band because its disk-shaped structure is viewed from within. Galileo Galilei first resolved the band of light into individual stars with his telescope in 1610. Until the early 1920s, most astronomers thought that the Milky Way contained all the stars in the Universe. Following the 1920 Great Debate between the astronomers Harlow Shapley and Heber Doust Curtis, observations by Edwin Hubble showed that the Milky Way is just one of many galaxies.