Since the Earth rotates on its axis, orbits around the Sun, and moves through the Galaxy and the Universe at the same velocity for each motion, we do not notice these motions.
It spins (rotates) at a speed of about 1,000 miles (1600 kilometers) per hour and orbits around the Sun at a speed of about 67,000 miles (107,000 kilometers) per hour. We do not feel any of this motion because these speeds are constant.
Earth spins on its axis once in every 24-hour day. At Earth's equator, the speed of Earth's spin is about 1,000 miles per hour (1,600 kph). You don't feel Earth spinning because you and everything else including Earth's oceans and atmosphere are spinning along with the Earth at the same constant speed.
We don't usually feel this movement because it is quite gradual – just a few millimetres every year. With time, the pressure of this movement builds up, and there is a sudden shift inside the Earth that we feel as an earthquake.
The primary contributors to heat in the core are the decay of radioactive elements, leftover heat from planetary formation, and heat released as the liquid outer core solidifies near its boundary with the inner core.
So, Earth travels about 1.6 million miles (2.6 million km) a day, or 66,627 mph (107,226 km/h).
If the planet were to come to an abrupt halt, the angular momentum imparted to the air, water and even rocks along the equator would keep moving at this speed of 1,100 mph. The movement would scour the surface while ripping it apart and sending shards into the upper regions of the atmosphere and outer space.
Without the Moon stabilising our tilt, it is possible that the Earth's tilt could vary wildly. It would move from no tilt (which means no seasons) to a large tilt (which means extreme weather and even ice ages).
If the Earth didn't spin, the night sky would always show the same constellations of stars, because you would always be looking out into space in the same direction. This is very different from seeing the stars rise and set during the night, and seeing different constellations at different times of the year.
The technology required to travel between galaxies is far beyond humanity's present capabilities, and currently only the subject of speculation, hypothesis, and science fiction. However, theoretically speaking, there is nothing to conclusively indicate that intergalactic travel is impossible.
At the Equator, the earth's rotational motion is at its fastest, about a thousand miles an hour. If that motion suddenly stopped, the momentum would send things flying eastward. Moving rocks and oceans would trigger earthquakes and tsunamis. The still-moving atmosphere would scour landscapes.
1000mph about its axis, is stopped, everything that is not anchored on earth will move the opposite direction at 1000mph and we'd all go crashing into things at that speed.
If the rotation would stop, we would feel an additional gravity of 0.034 m/s2, or about 0.35%, at the equator, (incorrectly) assuming the shape of Earth isn't changed by the changing rotation. The centrifugal acceleration is v2/r, with v=465.1 m/s, and r=6378100 m.
As there is no atmosphere on the surface of the moon, phenomena like rain and wind are not possible.
You might think it would suddenly become very cold. But it wouldn't. You wouldn't even notice the difference. Our planet has stored enough heat in its atmosphere and oceans to keep us warm for those five seconds without the Sun.
Long answer: The Moon is in a stable orbit around Earth. There is no chance that it could just change its orbit and crash into Earth without something else really massive coming along and changing the situation. The Moon is actually moving away from Earth at the rate of a few centimetres per year.
The most immediate consequence of destroying the Moon would be a much darker night sky. The Moon is the largest and most-reflective object in our sky, outside of the Sun of course. Losing it would make the rest of the sky comparatively brighter, which might be a nice side effect for ground-based deep-sky astronomers.
“So if the Moon got really close to the Earth, you'd have massive tides to contend with. There would be a lot of coastal flooding. There would be a lot more gravitational influence on the interior of the Earth, so you might also churn up and heat some mantle, leading to a lot more volcanism and earthquakes.”
Light from a stationary source travels at 300,000 km/sec (186,000 miles/sec).
"We cannot move through the vacuum of space faster than the speed of light," confirmed Jason Cassibry, an associate professor of aerospace engineering at the Propulsion Research Center, University of Alabama in Huntsville.
The Hubble Deep Field, an extremely long exposure of a relatively empty part of the sky, provided evidence that there are about 125 billion (1.25×1011) galaxies in the observable universe.
Apparently, Earth has actually been speeding up for a few years now. In 2020, it set new records no less than 28 times, according to Time and Date, despite the last record being set all the way back in 2005. This trend looks set to continue in 2022, but scientists are yet to agree on why Earth's spin is speeding up.
The Earth will never stop rotating. Earth rotates in the purest, most perfect vacuum in the whole universe—empty space. Space is so empty, so devoid of anything to slow the Earth down, that it just spins and spins, practically without friction.
Over millions of years, Earth's rotation has been slowing down due to friction effects associated with the tides driven by the Moon. That process adds about about 2.3 milliseconds to the length of each day every century. A few billion years ago an Earth day was only about 19 hours.