Astronomical Terms Part-1

                             

                                                           Astronomic Terms 

What is Astronomy ?                                                                                                                                               Astronomy is a natural science that studies celestial objects and phenomena. It uses mathematics, physics, and chemistry in order to explain their origin and evolution. Objects of interest include planets, moons, stars, nebulae, galaxies, and comets. 

Let's learn about some astronomic terms  = 

1) Angular size and distance -                                                                                                                                             The apparent size of an object in the sky, or the distance between two objects, measured as an angle. Your index finger held at arm’s length spans about 1°, your fist about 10°.  

2) Aperture -                                                                                                                                                                                    The diameter of a telescope’s main lens or mirror — and the scope’s most important attribute. As a rule of thumb, a telescope’s maximum useful magnification is 50 times its aperture in inches (or twice its aperture in millimeters).      

3)Asterism -                                                                                                                                                                        Any prominent star pattern that isn't a whole constellation , is  known as 'Asterism'.                                  Some examples are , The Northern Cross and The Big Dipper .

4) Asteroid -                                                                                                                                                                 A small rocky body orbiting the sun. Large numbers of these, ranging enormously in size, are   found between the orbits of Mars and Jupiter, though some have more eccentric orbits.

5) Astronomical Unit  -                                                                                                                                               The average distance from Earth to the Sun, slightly less than 93 million miles (150 million kilometers).   

6) Averted Vision -                                                                                                                                                       Viewing an object by looking slightly to its side. This technique can help you detect faint objects that are invisible when you stare directly at them.   

 

7) Baily's Beads -                                                                                                                                                     A few "beads" of sunlight, shining between mountain peaks and through the valleys along the Moon's edge in the moment before totality.    

8) Barlow Lens                                                                                                                                                            A lens that’s placed into the focusing tube to effectively double or triple a telescope’s focal length and, in turn, the magnification of any eyepiece used with it.   

9) Blue Moon -                                                                                                                                                             Traditionally , something happens rarely or never . More recently , this has to come to mean the second full moon in a single calendar month.

10) Celestial Coordinates -                                                                                                                                          A grid system for locating things in the sky. It’s anchored to the celestial poles (directly above Earth’s north and south poles) and the celestial equator (directly above Earth’s equator). Declination and right ascension are the celestial equivalents of latitude and longitude.

For more information please refer to the site given below -                                                                      https://skyandtelescope.org/astronomy-terms/  . 

Stay tuned !