What is the celestial instability process ? 20

Dai Wensai, deputy director of the Department of Mathematics and Astronomy at Nanjing University, wrote a few years ago that "the distance between the sun and the observer changes in one day". He also combined the documents of the Fourth Symposium on Astroevolution of the USSR Academy of Sciences and wrote about the "Significance of the Study of Unstable Stars in Astroevolution".

The landlord can go and have a look.

To put it simply, starting with a nebula - planetary nebula (beginning of evolution towards a star) - infrared star (beginning of internal reactions) - main-sequence star - and then depending on the mass, the sun and those less than the mass of the sun will smoothly walk up to the red giant-white dwarf-black dwarf. The lower limit of the mass of a novae or supernovae is a few inverted solar masses or more. This intense burst is followed by the emergence of neutron stars or black holes.

So the end of the star is either a black dwarf after complete extinction or a black hole that is constantly absorbing matter.

The second question is that there is no pressure in the universe, and a careful study of the definition of pressure will make it clear. The universe is not really a vacuum, and although matter is relatively thin, it still exists (and there are also galaxies, stars and other concentrations). Whether our space will shrink or not is still the focus of current research, depending on the total mass in our universe, whether gravity will win or the initial velocity inertia provided by the large ** will win is still inconclusive.

Eventually, it will either continue to expand, or retract or slow down until it remains at rest. We don't know what will happen after it shrinks to a singularity, but it is very likely that being at rest and expanding will cause our universe to be a heat death after a long time, becoming a uniform soup of elementary particles.

To answer your second question, the space we know now is rotating, centrifugal action cancels out a large part of the gravitational force, and with the mass of the stars themselves, the universe will not collapse soon, at least we can't see it.

As for the first question, it is very simple to find.

The evolution of stars can be roughly divided into the following stages: 1. The main sequence is the previous stage Stars are in their infancy. 2. The main sequence is the star phase Stars are in their prime.

3. Red Giant Stage Stars are in middle age. 4. White Dwarf Stage Stars are in old age. This is the case with most stars.

It can generally be considered that the predecessor of the star was the nebula.

In addition, black holes, neutron stars, brown dwarfs, black dwarfs, and supernovae are all products of stellar evolution, and the second problem is the second problem.

Because what you see on Earth is a vacuum compressed is because there is air pressure on the Earth, and this pressure difference causes compression.

But the universe is equal in its eyes, it's almost zero, so space doesn't compress, the centrifugal force and the gravitational force between the celestial bodies are almost balanced by each other, but they're all moving in motion, it's not static, you don't understand, the universe itself expands, it doesn't collapse for the time being, but in the future, there are three ways to say the fate of the universe.

1 Endless Expansion 2 Stable 3 Collapse Retract Singularity.

According to the mainstream theory of astroevolution, a star of mass such as the Sun will eventually become a white dwarf, that is, a dying star, which is very dense and extremely hot, but small in size (compared to stars in the prime of life), and finally its energy is exhausted, and it will gradually extinguish and become a black dwarf that does not emit light, which can be considered to be the grave of the sun.

The current Sun is in the main-sequence phase, that is, in the prime of life. In another four or five billion years, the red giant phase will begin to expand, and the Earth will begin to expand beyond the Earth's orbit, which means that the Earth will be swallowed up. Don't worry, humanity at that time would have had the perfect solution long ago and would leave the earth that nurtured us.

Then the sun will explode into a magnificent supernova --- the future, throwing out the outer gas shell, and compressing the interior into a white dwarf under a huge reaction.

This is the end-stage evolution of the sun. The evolution of stars with different masses at the end of the stellar period is different. To put it simply, stars with less than or equal to three solar masses will eventually become white dwarfs, just like the Sun; Stars larger than three times the mass of the Sun collapse into black holes.

Original by my rich astronomical knowledge, never copy books, I hope you are satisfied.

During the evolution of the Sun, the brightest star is the helium flash at the end of the Sun's main sequence phase.

The densest star is the late solar - white dwarf.

The densest objects in the universe are neutron stars. (Black holes have no density to speak of, and density is a physical quantity that fails at black holes).

The first question, red superstar; The second question, the white dwarf.

I'm not sure.

Dust clouds – primordial stars – Sun – red giants – white dwarfs – black dwarfs (ends).

So I'll take the example of the sun, which in the universe was first gas, dust, or a mixture of both. These mixtures have been in the universe for quite some time. There is an interstellar dust cloud called the primordial solar nebula, which at some point begins to collapse by gravity, shrinking in size and increasing in density and temperature, and after shrinking to a million times, it becomes a primordial star.

At this time, its temperature has reached almost 10 million degrees. As his temperature continues to rise after exceeding 10 million degrees. It had the same reaction of the hydrogen bomb ** - please fuse the reaction.

That's when a star called the Sun was born. (Tired of fighting).

The sun wasn't stable at this time, and it took 5 billion years for it to stabilize. After stabilization, how can it last for about 10 billion years? It is our sun now ...

In the Sun's later years will become a red giant. A red giant is (explained later) that the heat of the contraction of the Sun's core will cause the outside to expand and become a red giant. The helium-filled core continues to shrink and the temperature increases.

When the temperature of the core region rises to 100 million degrees, the helium fusion reaction begins, and the three heliums fuse into carbon after a series of nuclear reactions, releasing a greater amount of light and heat than the hydrogen fusion reaction, causing the outer layer of the sun to expand rapidly, and even the earth is engulfed, becoming a super-large red supergiant. (End of information).

Eventually, as the red giant continues to consume, the Sun will become a white dwarf, because all the carbon is squeezed together, and his pressure resists the gravitational contraction. But because the white dwarf does not and reflects the supply of light and heat.

So he's going to end up being a black dwarf, which is the end of the sun.

It's a lighter star with a heavier mass and it's not the same as this one. If you think you can share it with me...Pure hand-to-hand hitting.

1l is talking about a small mass star.

The end of massive stars is neutron stars;

Larger masses become black holes.

Light is matter?

Yes, according to Einstein's theory, light is a particle that moves in the form of a wave.

Is there quality? Yes, but the mass is very small.

It is said that celestial bodies that cannot escape are called "black holes", and that light is deflected when it passes over larger bodies.

Universal gravitation.

Light is a substance and has no static mass. Massive celestial bodies have a large gravitational pull, and gravity can bend space according to general relativity, so light can only walk along the curved space, which is the deflection of light that we see, that is, gravitational lensing. The gravitational pull of a black hole is even greater, and it can distort space so much that light cannot escape within its event horizon.

Light is a substance that embodies two properties: wave-particle duality.

Light has mass, which is static mass and dynamic mass.

Light is deflected because of gravity, or gravitational lensing

Light is matter?

There is quality. Sorry, black holes aren't defined that way.

Light is deflected when it passes over a larger celestial body, and the gravitational pull is good.

Solution: Since the gravitational force of the earth experienced by the satellite = centrifugal force of the motion of the satellite gmm (r 2) = (mv 2) r

i.e.: gm r=v 2

Again r=v w

gmw/v=v^2

v=(gmw)^(1/3)

and w = 2 t

v=(2πgm/t)^(1/3)