Planets questions

The rings of Saturn are the planetary rings around the planet Saturn, which can be seen with a small telescope.The particles in the rings are made almost entirely of water ice, with just a small amount of dust and other chemicals. There are some gaps in the rings. The moon Pan causes the gap called the "Encke gap" in Saturn's A ring. The Cassini Division, discovered by Giovanni Domenico Cassini, is a gap between the A ring and the B ring. It is a product of orbital resonance.

Henry Cavendish, british physicist (1731-1810) was the first scientist to calculate mass of the Earth. Greater accuracy has not been achieved for nearly 100 years. He only made a mistake about 1% compared to today's calculations. Cavendish estimated the mass of the Earth to be 6 billion trillion tons. Modern calculations say about 5.9725 billion trillion tons. (5,97219×10^24 kg)

Pluto, our tiny intrasolar neighbor, has a surface area of only a scant 6.45 million square miles. That might seem like quite a few square miles to sling around, but by comparison, that’s only one-third of one percent of the Earth’s total surface and small enough to fit entirely within the borders of Russia (6.6 million square miles). Pluto is a dwarf planet in the Kuiper belt, a ring of bodies beyond Neptune. It was the first Kuiper belt object to be discovered and is the largest known plutoid (or ice dwarf).

Janus [JAY-nus] is the sixth satellite of Saturn. It was discovered by Audouin Dollfus in 1966 and was named after the god of gates and doorways. It is depicted with two faces looking in opposite directions.

The dwarf planet Pluto has five moons down to a detection limit of about 1 km in diameter. In order of distance from Pluto, they are Charon, Styx, Nix, Kerberos, and Hydra. Charon, the largest of the five moons, is mutually tidally locked with Pluto, and is massive enough that Pluto–Charon is sometimes considered a double dwarf planet.

A terminator or twilight zone is a moving line that divides the daylit side and the dark night side of a planetary body. A terminator is defined as the locus of points on a planet or moon where the line through its parent star is tangent. An observer on the terminator of such an orbiting body with an atmosphere would experience twilight due to light scattering by particles in the gaseous layer.

The average distance between Saturn and the Sun is over 1.4 billion kilometers (9 AU). With an average orbital speed of 9.68 km/s, it takes Saturn 10,759 Earth days (or about ​29.5 years) to finish one revolution around the Sun.

Saturn is not solid like Earth, but is instead a giant gas planet. It is made up of 94% hydrogen, 6% helium and small amounts of methane and ammonia. Hydrogen and helium are what most stars are made of. It is thought that there might be a molten, rocky core about the size of Earth deep within Saturn.

Gravitational force is an example of a conservative force, while frictional force is an example of a non-conservative force. Other examples of conservative forces are: force in elastic spring, electrostatic force between two electric charges, and magnetic force between two magnetic poles.

NASA is back to one of its favorite hobbies — otherworldly cloud gazing — thanks to the Juno spacecraft currently in orbit around Jupiter. The community's votes have resulted in incredible photos like this one. At the time, the spacecraft was conducting its 16th skim over Jupiter's surface, coming within just 4,400 miles of the top of Jupiter's cloud system.