Search results
Results From The WOW.Com Content Network
Mars ♂ Moons of Mars; ... at about 4.4 light years away; ... Physical characteristics of Uranus Structure of Uranus; Atmosphere of Uranus;
In order from the Sun, they are four terrestrial planets (Mercury, Venus, Earth and Mars); two gas giants (Jupiter and Saturn); and two ice giants (Uranus and Neptune). All terrestrial planets have solid surfaces. Inversely, all giant planets do not have a definite surface, as they are mainly composed of gases and liquids. Over 99.86% of the ...
The pronunciation of the name Uranus preferred among astronomers is / ˈ jʊər ə n ə s / YOOR-ə-nəs, [1] with the long "u" of English and stress on the first syllable as in Latin Uranus, in contrast to / j ʊ ˈ r eɪ n ə s / yoo-RAY-nəs, with stress on the second syllable and a long a, though both are considered acceptable. [g]
The length of a day on Uranus as measured by Voyager 2 is 17 hours, 14 minutes. [49] Uranus was shown to have a magnetic field that was misaligned with its rotational axis, unlike other planets that had been visited to that point, [50] [53] and a helix-shaped magnetic tail stretching 10 million kilometers (6 million miles) away from the Sun. [50]
In astronomy, the rotation period or spin period [1] of a celestial object (e.g., star, planet, moon, asteroid) has two definitions. The first one corresponds to the sidereal rotation period (or sidereal day ), i.e., the time that the object takes to complete a full rotation around its axis relative to the background stars ( inertial space ).
Such a fate awaits the moons Phobos of Mars (within 30 to 50 million years), [111] Triton of Neptune (in 3.6 billion years), [112] and at least 16 small satellites of Uranus and Neptune. Uranus's Desdemona may even collide with one of its neighboring moons. [113] A third possibility is where the primary and moon are tidally locked to each other ...
According to the IAU's explicit count, there are eight planets in the Solar System; four terrestrial planets (Mercury, Venus, Earth, and Mars) and four giant planets, which can be divided further into two gas giants (Jupiter and Saturn) and two ice giants (Uranus and Neptune). When excluding the Sun, the four giant planets account for more than ...
The ancient Greek astronomer Hipparchus noted the apsidal precession of the Moon's orbit (as the revolution of the Moon's apogee with a period of approximately 8.85 years); [4] it is corrected for in the Antikythera Mechanism (circa 80 BCE) (with the supposed value of 8.88 years per full cycle, correct to within 0.34% of current measurements). [5]