Search This Blog

Wednesday, January 11, 2023

moons of Uranus !!

It is considered very attractive .. .. it influence causes romantic moods !  .. .. Earth's Moon is the only place beyond Earth where humans have set foot.  In 1969, Neil Armstrong's first footstep on the Moon signified a giant leap for humanity. It also symbolised the United States’ victory in the space race while reinforcing its geopolitical supremacy. Now, more than five decades later, another ‘space race’ to the Moon appears to be underway. But this time, joining the U.S. and the Soviet Union (now Russia) on this front is  China.

The brightest and largest object in our night sky, the Moon makes Earth a more livable planet by moderating our home planet's wobble on its axis, leading to a relatively stable climate. It also causes tides, creating a rhythm that has guided humans for thousands of years. The Moon was likely formed after a Mars-sized body collided with Earth.

After going through a bleak 2022 with no successful space launch, a situation unseen in 18 years, Japan said  that it aims to become the second country after the US to land astronauts on the moon, adding it will strengthen cooperation with the US to counter China's space endeavours.  However, to some,  Japan's putting its astronauts on the moon via another country's spacecraft, while calling itself "second in history" is laughable, warning that if Japan continues to rely heavily on the US, it will eventually lose the ability to walk on its own, thus becoming a puppet of the US.  

Frederick William Herschel  [1738 – 1822] was a German-born British astronomer and composer. He frequently collaborated with his younger sister and fellow astronomer Caroline Herschel.  Born in the Electorate of Hanover, William Herschel followed his father into the military band of Hanover, before emigrating to Great Britain in 1757 at the age of nineteen. Herschel constructed his first large telescope in 1774, after which he spent nine years carrying out sky surveys to investigate double stars. Herschel published catalogues of nebulae in 1802 (2,500 objects) and in 1820 (5,000 objects). The resolving power of the Herschel telescopes revealed that many objects called nebulae in the Messier catalogue were actually clusters of stars.  Herschel pioneered the use of astronomical spectrophotometry, using prisms and temperature measuring equipment to measure the wavelength distribution of stellar spectra.

Like the classical planets, Uranus is visible to the naked eye, but it was never recognised as a planet by ancient observers because of its dimness and slow orbit. Sir William Herschel first observed Uranus on 13 March 1781, leading to its discovery as a planet, expanding the known boundaries of the Solar System for the first time in history and making Uranus the first planet classified as such with the aid of a telescope.  

Uranus is the seventh planet from the Sun. It is named after Greek sky deity Uranus (Caelus), who in Greek mythology is the father of Cronus (Saturn), a grandfather of Zeus (Jupiter) and great-grandfather of Ares (Mars). Uranus has the third-largest planetary radius and fourth-largest planetary mass in the Solar System. The planet is similar in composition to Neptune, and both have bulk chemical compositions which differ from those of the other two giant planets, Jupiter and Saturn (the gas giants). For this reason, scientists often distinguish Uranus and Neptune as "ice giants". As with gas giants, ice giants lack a well-defined solid surface.  Like the other giant planets, Uranus has a ring system, a magnetosphere, and numerous moons.  

Uranus, the seventh planet of the Solar System, has 27 known moons, most of which are named after characters that appear in, or are mentioned in, the works of William Shakespeare and Alexander Pope.  Uranus's moons are divided into three groups: thirteen inner moons, five major moons, and nine irregular moons.  

The first two moons to be discovered were Titania and Oberon, which were spotted by Sir William Herschel on January 11, 1787, six years after he had discovered the planet itself.   The other three ellipsoidal moons were discovered in 1851 by William Lassell (Ariel and Umbriel) and in 1948 by Gerard Kuiper (Miranda). These five may be in hydrostatic equilibrium, and so would be considered dwarf planets if they were in direct orbit about the Sun. The remaining moons were discovered after 1985, either during the Voyager 2 flyby mission or with the aid of advanced Earth-based telescopes.

Interesting !  

With regards – S. Sampathkumar

No comments:

Post a Comment