Christmas Star

Why in news?

• The solar system's two biggest planets, Jupiter and Saturn, came in extremely close range on December 21^st evening sky.

About the phenomenon:

• After nearly 400 years, Saturn and Jupiter – the two largest planets in our solar system – will be brought closest in the night sky by an astronomical event called the “great conjunction” and popularly referred to as the “Christmas Star”. 
• The event will coincide with the winter solstice (shortest day of the year in terms of hours of sunlight received) in the Northern Hemisphere and summer solstice in the Southern Hemisphere.
• A conjunction is not unique to Saturn and Jupiter however, it is the name given to any event where planets or asteroids appear to be very close together in the sky when viewed from the Earth
• The “Great Conjunction” between the two giant planets happens once in about 20 years because of the time each of the planets take to orbit around the Sun when Jupiter (with orbital period of 12 years) catches up with Saturn (which 30 years).
• This year, because of the alignment between them, the planets will appear to be especially close to each other in the sky to viewers on Earth at about a tenth of a degree, an closeness that occurs only once in four centuries.

Prelims Question

Consider the following statements: 
1.The Rings of Saturn are an optical illusion created by refraction of Sunlight 
2.Jupiter has the largest number of known satellites of any planet in the solar system.
Which among the above statements is/are correct?
(a)1 only 
(b)2 only 
(c)Both 1 and 2
(d)Neither 1 nor 2

Answer to prelims question