Cycles in the sky
Under the dark sky we can see thousands of stars if we watch it for few hours we can see rise and set as the earth rotates once a day and if you go outside next night at the same time we can see the things pretty much the same as they did appear on the last night before, the stars rise and set Polaris hang to the north and so on. One day hardly makes any difference to the sky’s appearance.
But if you wait for an another night or a week we can spot subtle changes in the sky.
What is Constellation
A cluster or group of stars in the sky that are grouped or formed together in a particular pattern and have been given a name called constellation. A group of constellations form zodiac. Thirteen constellations have been studied and tracked from ancient times.
Stars Appear To Rise And Set:
As an Observer with your eyes without any instruments if you see few starts after a week the start which appears to be on the top will be moved to the downwards, and the stars which used to be appear on the left will be moved aside. If you wait for a month and see this effect is pronounced all new constellations will be visible in the sky after sunset. This is because the earth is going around the sun, literally changing our viewpoint on the sky.
Earth takes a year to orbit the sun once, everyday it moves a little bit along its orbit and it does from earths perspectives, distant stars appear to move their positions relative to the sun. So, one day we might see a star near to the sun, but the next day the angle is bit bigger. At some point about six months after we first saw, the star is directly opposite the sun and the sky. Then the angle shrinks again as the star approaches the sun from the opposite side, until after a full year, the cycle repeats.
Stars in the east rise about 2 mins earlier at night start at west sets at 2 mins earlier, a constellation that was entirely below the east horizon at sunset one month might be completely visible after sunset the next month.
Also Read:
1) What is Astronomy : When its Day and Night
2) Everything About Earthquake: Types, Impact, Measure and Earthquake Causes
3) 1st Interstellar Asteroid Oumuamua 2017 U1 Discovered
4) Mercury Planet Information for Kids and Characteristics of Budh Planet
5) What Are The Fields Of Science
Ecliptic:
The Sun seems to move against the background stars as seen from the orbiting Earth. The ecliptic is the path the Sun appears to trace through the stars. This process repeats itself on a cycle lasting a little over 365 days. The path that seems to take and the path that the zodiac sits upon is what the astronomers called An Ecliptic.
Another way to think about it is starts appear to be fixed and as the earth circles the sun , the sun moves through the stars over the course of the year making a complete cycle circle around the sky once per year. The path it takes is a reflection of the earths path around the sun, a line in the sky. We call that line Ecliptic.