its important

1. Motions of earth

2. Rotation
 Earth's rotation or Earth's spin is the rotation of planet Earth around its own axis, as
well as changes in the orientation of the rotation axis in space. Earth rotates eastward,
in prograde motion. As viewed from the north pole star Polaris, Earth
turns counterclockwise.
 The North Pole, also known as the Geographic North Pole or Terrestrial North Pole, is the
point in the Northern Hemisphere where Earth's axis of rotation meets its surface. This
point is distinct from Earth's North Magnetic Pole. The South Pole is the other point where
Earth's axis of rotation intersects its surface, in Antarctica.
 Earth rotates once in about 24 hours with respect to the Sun, but once every 23 hours, 56
minutes, and 4 seconds with respect to other, distant, stars (see below). Earth's rotation is
slowing slightly with time; thus, a day was shorter in the past. This is due to the tidal
effects the Moon has on Earth's rotation. Atomic clocks show that a modern-day is longer
by about 1.7 milliseconds than a century ago,[1] slowly increasing the rate at which UTC is
adjusted by leap seconds. Analysis of historical astronomical records shows a slowing
trend; the length of a day increased about 2.3 milliseconds per century since the 8th
century BCE] Scientists reported that in 2020 Earth has started spinning faster, after
consistently slowing down in the decades before. Because of that, engineers worldwide
are discussing a 'negative leap second' and other possible timekeeping measures.[3]

3. Orbital revolution
 Orbital revolution is the movement of a planet around a star, or a moon around
a planet. For example, the Earth revolves around the Sun, and the Moon revolves
about the Earth.
 Planets and moons revolve in elliptical orbits. One orbital revolution of a planet
takes one year, while a revolution of the Moon takes a month.
 Astronomers usually use different words for the orbit of a planet around a star,
and for the spin of a planet about its own axis. If an item is in orbit, it is
"revolving", while the spin of a planet is called "rotating". The amount of time it
takes for an object to revolve around the Sun is a year, and the amount of time it
takes to revolve around its axis is one day. According to the Gregorian calendar, a
year on Earth is equal to 365 days, with an extra day added every four years.
 The amount of time it takes for an object to move around the sun is different for
every object. For example, it takes the planet Mercury about 88 daya to revolve
around the sun, but it takes the dwarf planet Pluto over 248 years to revolve
around the sun.

4. Summer solstice
The summer solstice, also known as estival
solstice or midsummer, occurs when one of the
Earth's poles has its maximum tilt toward the Sun. It happens
twice yearly, once in each hemisphere (Northern and Southern).
For that hemisphere, the summer solstice is when the Sun
reaches its highest position in the sky and is the day with the
longest period of daylight. Within the Arctic circle (for the northern
hemisphere) or Antarctic circle (for the southern hemisphere),
there is continuous daylight around the summer solstice. On the
summer solstice, Earth's maximum axial tilt toward the Sun is
23.44°.[3] Likewise, the Sun's declination from the celestial
equator is 23.44°.

5. Winter solstice
 The winter solstice, hiemal solstice or hibernal
solstice occurs when one of the Earth's poles has its maximum
tilt away from the Sun. It happens twice yearly, once in each
hemisphere (Northern and Southern). For that hemisphere, the
winter solstice is the day with the shortest period of daylight and
longest night of the year, when the Sun is at its lowest daily
maximum elevation in the sky.[3] At the pole, there is continuous
darkness or twilight around the winter solstice. Its opposite is
the summer solstice. Also the Tropic of Cancer or Tropic of
Capricorn depending on the hemispheres winter solstice the
sun goes 90 degrees below the horizon at solar midnight to
the nadir.

6. equinox
 An equinox is the instant of time when the
plane of Earth's equator passes through the geometric center of
the Sun's disk.[3] [4]This occurs twice each year, around 20
March and 23 September. In other words, it is the moment at
which the center of the visible Sun is directly above the equator.