Physics
Charge Coupled Devices in Astronomy
Charge Coupled Devices first developed in the 1960s as memory storage devices. Sensitivity to light suggested imaging possibilities. Her briefly focus on History of CCDs; How do CCDs…
Lecture
Physics
Lecture on Atmospheric Turbulence
Major objective of this lecture is to present on Atmospheric Turbulence. The atmosphere is an inhomegeneous medium with varying index of refraction in both time and space. Turbulence…
Physics
Diffraction of Rayleigh Criterion
The aim of this lecture is to present on Diffraction of Rayleigh Criterion. The telescope aperture produces fringes (Airy disc) that set a limit to the resolution…
Physics
Advantages of Heliocentric Model
Prime objective of this lecture is to present on advantages of Heliocentric Model. Main advantages of Heliocentric Model is easier to compute, correct orbital radii, predicts…
Physics
What is Planet?
General objective of this lecture is to present on What is Planet. The definition of planet, since the word was coined by the ancient Greeks, has included within its scope…
Physics
Ptolemy’s Geocentric Model
Ptolemy was approximating Kepler’s law, without knowing it. The reasons are: the elliptical orbits of the planet are close to a circle; the eccentric takes the role of…
Physics
Aristotle’s Model of Universe
Aristotle’s (384-322 BCE) model placed the superior planets in right order using their speed on the celestial sphere. He established a geocentric universe in which the…
Physics
Examples of Planetary Events
Principle purpose of this lecture is to present on Examples of Planetary Events. Some events are; Conjunctions: Two objects closest from Earth’s point of view. Stationary: When the ecliptic longitude…
Physics
What is the cause for Precession of Equinoxes?
Major purpose of this lecture is to present on cause for Precession of Equinoxes. Precession is caused by the torque applied by the Sun, the Moon, and…
Physics
Relation between Solar motion and the Calendar
The Sun’s position relative to Vernal Equinox is important for determining the seasons and the calendar. A major function of the calendar was for agriculture. Solar…
Physics
Where is the Center of Celestial Sphere?
The celestial sphere is a device used to represent the direction of celestial objects for observation. For example, someone in Beijing would see the Moon’s…
Physics
What is Constellation?
The term “constellation” is also less formally used to describe a group of star visibly related to each other in a pattern, such as those…
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