A regolith is a collective term referring to the blanket of powdery materials that cover the surface of several celestial bodies such as the earth, moon, and asteroids among many others. This blanket has a powdery appearance and texture because it is composed of fine debris such as soil, shattered rock, dust, and other small objects that tend to land on the surface of these celestial bodies.
A polar ice cap is that region at either poles of a planet or natural satellite that is permanently covered in ice. It is different from an ice cap in that there are no specifications on the size or composition of a body of ice for it to be considered a polar ice cap. Whereas an ice cap needs to be found over land that has a specific surface area, a polar ice cap just has to be a body [...]
The Sun, Moon, stars and other celestial objects are beyond the reach of any instrument that can be used by observers here on Earth. Measuring the distance of a celestial object from the Earth might seem to be complicated. But measuring the distance of these remote entities have been simplified by the concept of parallax.
Libration refers to the movement of orbiting bodies in relation to one another. For instance, the movement of the Moon Relative to the Earth is an example of a Libration. One of the common examples of Libration is Lunar libration. The moon consists of a singular hemisphere, which faces the earth. Over time more of the Moon’s surface more than 50 percent of the surface of the Moon has started to be visible to the earth because of Libration. In [...]
Tidal force is a secondary effect of gravitational force and its most common manifestation, at least on the planet Earth, are tides. Tidal force, by technical definition is the differential force of gravity which arises because the force exerted on one body by another is not constant across the diameter in that the side which is the nearest to the second body is subject to more gravitational force compared to the side farther away.
Merriam-Webster dictionary defines gibbous as marked by convexity or swelling, seen with more than half but not the entire apparent disk illuminated or having a hump. It also means characterized by being protuberant. When used on celestial bodies, it is when more than half but less than full of the surface is illuminated.
The Galilean moons/satellites are Jupiter’s four moons discovered by Galileo Galilei. Jupiter has many moons that orbits around it. These four moons are the largest of those moons. And its names were derived from the lovers of Greek god, Zeus. Those are Io, Europa, Ganymede and Callisto. Io is the innermost Galilean moon. It is the 4th largest moon in the solar system. It was referred as the first satellite of Jupiter. Europa is the second moon of the four. [...]
Synchronous rotation is an astronomical term that is used to describe a celestial body orbiting another celestial body in a manner such that the orbiting body takes as long to rotate on its axis as it does to make one orbit. Therefore, it always keeps the same hemisphere pointed at the celestial body it orbits around.
Photo by: Mbz1 Creative Commons Tides are the periodic fluctuations of large bodies of water. They are caused by the gravitational interaction between the Earth and the Moon in what is generally called tidal forces. Although tidal changes may occur as a result of other factors like the Moon’s altitude and distance, the positions of the sun and the Earth and the depth of ocean floors and coastal topography.
A Trojan, in Astronomy, is a minor planet or moon that shares an orbit with a larger planet or satellite but does not collide with the larger planet because while it orbits, it stays safely in what is called as the Lagrangian points. In theory, there are also Trojan planets that may reside at Trojan points.