Komet memiliki orbit atau lintasan yang berbentuk elips, lebih lonjong
dan panjang daripada orbit planet. Komet yang cerah pastinya menarik
(My answer is 3021)
Leap years is a year with 29 February when the common years end with 28 February. It'shappend when the number of year can divisible by 4, or after 3 common years then there'sa leap year. Introduce by Julius Caesar in 45 BC and the first leap years were 45 BC, afterthat : 42 BC, 39 BC, 36 BC, 33 BC, 30 BC, 27 BC, 24 BC, 21 BC, 18 BC, 15 BC, 12 BC, 9 BC,AD 8, AD 12, and every 4th year from then on.Some disagree about whether 45 BC was a leap year or not. There were no leap yearsbetween 9 BC and AD 8 (or, according to some, between 12 BC and AD 4). Please rememberthere's no 0 AD, after 1 BC then 1 AD.A year (or precisely a tropical year) is define as the time between two vernal equinoxes (notone revolution of the earth), according to our modern calculation the length is 365,24219days, but it varies. Or other definition say the length of time that the Sun takes to return tothe same position in the cycle of seasons. Vernal equinoxes fall near 20 or 21 March, thebeginning of the spring season in northern hemisphere.Ancient Egypt (2780 BC) has already known the length of 1 year is 365,25 days. In the 2ndcentury BC, Hipparcchus can count the length of 1 tropical year to be 365 days, 5 hours, 55minutes and 12 seconds (or 365,24667 days). The Roman emperor take 1 year is 365,25days, and with the help from Sosigenes, a mathematician from Alexandria, Julius Caesar in45 BC made this leap years rules (called Julian calendar) with the purpose to make theseasons always came in the same days every years. There's problem with this leap years rules , because there's different between 1 Rome year(365,25 days) and the tropical year (365,24219). Roman's year have 11 minutes and 14second to long from the tropical year, so theres addition one day every 128 year! After 400years, there's 3 excess days thats mean the spring season is shift 3 days earlier (on 17 or18 March).