Yuga

Yuga refers to a large unit of time, era, or epoch. There are four Yugas that happen
sequentially, and the four of them collectively loop, creating an endless loop of time.

Timing of the Yugas

^{By Stephen Knapp}

When describing the length of the yugas or ages, and which yuga we are
in and how far along we are in it, there is sometimes confusion about how
to calculate them. The problem is when they are figured only according
to years of earth's time, they will never be accurate. They are described
in the Vedic literature according to the celestial years, or years of the
devas. Nonetheless, there are specific references in the Vedic texts which
make it clear how to calculate them. For starters, the Mahabharata (Shanti
Parva, 231.12-20) explains it in detail:

The rishis, measuring time, have given particular names to particular portions
[of time]. Five and ten winks of the eye make what is called a Kastha.
Thirty Kasthas make what is called a Kala. Thirty Kalas, with the tenth
part of a Kala, make a Muhurta. Thirty Muhurtas make one day and night.
Thirty days and nights form a month, and twelve months form a year. Persons
well-read in mathematical science say that a year is made up of two solar
motions, meaning the northern and southern. The sun makes the day and night
for men. The night is for the sleep of all living creatures, and the day
is for work. A month of human beings is equal to a day and night of the
departed manes [ancestors who have gone on to the subtle worlds]. That
division consists in this: the light half of the month is their day which
is for work; and the dark fortnight is their night for sleep. A year (of
men) is equal to a day and night to the gods [devas or celestials]. This
division consists in this: the half year for which the sun travels from
the vernal to the autumnal equinox is the day of the gods, and the half
year for which the sun moves from the latter to the former is their night.
[Thus, an earth year is but a day for the devas.] Calculating by the days
and nights of human beings about which I have told you, I shall speak of
the day and night of Brahma and his years also. I shall, in their order,
tell you the number of years, that are for different purposes calculated
differently, in the Krita, the Treta, the Dvapara, and the Kali Yugas.
Four thousand celestial years is the duration of the first or Krita age.
The morning of that cycle consists of four hundred years and its evening
is of four hundred years. [Note: This says celestial years, or years of
the demigods on the higher planets. Such years are much longer than those
of planet earth. So 4000 celestial years, with the morning or Sandhya of
400 celestial years and the evening or Sandhyansa, or intermediate period,
of another 400 years, equals 4800 celestial or divine years and 1,728,000
human years.]

Regarding the other cycles, the duration of each gradually decreases by
a quarter in respect of both the principal period with the minor portion
and the conjoining portion itself. These periods always keep up the never-ending
and eternal worlds. They who know Brahma, O child, regard this
as Immutable Brahma. (Mb, Shanti Parva, Chap.231, Text 21-22)

This means that as each age appears, from the Krita, Treta, Dvapara to
Kali, each yuga decreases by a quarter of the previous yuga, in addition
to the conjoining Sandhya and Sandhyansa periods with each yuga. In this
way, it is roughly calculated that a whole cycle of the four yugas, namely
Krita, Treta, Dvapara and Kali-yuga together, total about 12,000 celestial
years in length.

The Mahabharata (Shanti Parva, 231.29-32) continues: "The learned say that
these 12,000 celestial years form what is called a cycle. A thousand such
cycles form a single day of Brahma. The same is the duration of Brahmas
night. With the beginning of Brahma=s day the universal entities come into
being. During the period of universal dissolution the Creator sleeps in
Yoga-meditation. When the period of sleep expires, He awakes. What is Brahma's
day covers a thousand such cycles. His night also covers a thousand similar
cycles. They who know this are said to know the day and the night. On the
expiry of His night, Brahma, waking up, modifies the indestructible intelligence
by causing it to be overlaid with ignorance. He then causes Consciousness
to spring up, whence it originates Mind which is at one with the Manifest.

In calculating the duration of the different yugas, there are a few differences
between the Puranas. The Brahmanda Purana (1.2.29.31-34) specifically states
that Krita or Satya-yuga is 1,440,000 human years in length, Treta-yuga
is 1,080,000 years, Dvapara-yuga is 720,000 years, and Kali-yuga is 360,000
years in length. The Linga Purana (4.24-35) also agrees with this except
for Treta-yuga, which it says is 1,800,000 years in length.

However, when explaining the various measurements of time, the Vishnu Purana
(Book One, Chapter Three) and the Bhagavata Purana (3.11.19), along with
the Bhagavad-gita (8.17) and the Vayu Purana (Chapter 57) and others, such
as the Mahabharata as quoted above, all agree on the measurements of the
durations of the yugas, as explained below.

In the explanations of the measurements of time found therein, one cycle
of the four yugas together is 12,000 years of the demigods, called divine
years. Each of these years is composed of 360 days, and each of their days
is equal to one human year. So Krita-yuga is 4000 divine years in length,
Treta-yuga is 3000 divine years in length, Dvapara-yuga is 2000 divine
years in length, and Kali-yuga is 1000 divine years long, with the addition
of the conjoining portions of the Sandhya and Sandhyansa.

In this way, each yuga is preceded by a period called a Sandhya, which
is as many hundred years in length as there are thousands of years in that
particular yuga. Each yuga is also followed by a period of time known as
a Sandhyansa, which is also as many hundreds of years in length as there
are thousands of years in the yuga. In between these periods of time is
the actual yuga. Therefore, we have:

Krita-yuga = 4000 divine years, Sandhya = 400 divine years, Sandhyansa = 400
divine years. Total = 4800 divine years x 360 days = 1,728,000 human years.

Treta-yuga = 3000 divine years, Sandhya = 300 divine years, Sandhyansa = 300
divine years. Total = 3600 divine years x 360 days = 1,296,000 human years.

Dvapara-yuga = 2000 divine years, Sandhya = 200 divine years, Sandhyansa = 200
divine years. Total = 2400 divine years x 360 days = 864,000 human years.

Kali-yuga = 1000 divine years, Sandhya = 100 divine years, Sandhyansa = 100
divine years. Total = 1200 divine years x 360 days = 432,000 human years.

This equals 4,320,000 human years in one cycle of the four yugas together,
and 1000 cycles of these yugas equals 12,000 divine years and 4,320,000,000
human years in a day of Brahma.