How do scientists know that a star in the constellation Centauri, for example, is tens of light year

For example, the Earth observes the angle of a star to the Earth at the vernal and autumnal equinoxes, and then calculates its distance from the Earth from the Earth using the radius of its orbit as the baseline.

For more recent objects (within 500 light years), triangulation is used.

500 100,000 light-year objects use photometric methods to determine distances.

Astronomers 100,000 light-years away have found Cepheids as a standard, up to a range of 500 million light-years.

The longer distance is calculated using the observed redshift, based on Hubble's theorem.

It is said that the distance is calculated by calculation, and no one knows how much error there is! Anyway, I don't believe in the calculations.

1 light-year is the distance transmitted by a year of light, and some stars are millions of light-years away from us, or even hundreds of millions of light-years, then it means that light can travel endlessly in the universe for n years, and so many stars in the universe are shining at the same time Why does the earth still have night?

The constellation Centauri is located about light-years from Earth.

Centauri, one of the southern constellations, can only be seen in the southern provinces of China on a spring evening. There are two bright stars in the constellation, the star is called South Gate II in ancient China, and the magnitude of the star is the third bright star in the whole day; The ancient star is called the horse's belly, and the star magnitude is the eleventh bright star of the whole day. The two stars are so close together that they were collectively called the "South Gate Twin Stars" in ancient China, and were used by Zheng He to navigate the West in the 14th century.

South Gate 2 is a triple star with an 11th magnitude companion Li Bei Tuen (Proxima Centauri) only light-years away, which is the closest star to the orange solar system.

The constellation Centauri is about light-years from the Sun and consists of 3 stars, of which Star A and Star B resemble the Sun, forming a binary system called "Centauri AB"; Star C, named Proxima Centauri, is a small, faint red dwarf star that is the closest (about light-years) roll to the Sun.

Literature related to the constellation Centauri

1. Three-body trilogy.

In Liu Cixin's ** "Three-Body Problem", the Centauri is the location of the alien intelligent civilization Three-Body Civilization, and the Three-Body Man determined the location of the Earth civilization through the signal sent by the Red Bank Base, and then deployed an invasion of the solar system, and finally the Centaur was destroyed by the Dark Forest.

2. The Wandering Earth.

In Liu Cixin's ** "The Wandering Earth", in order to solve the problem after the sun becomes a red giant, human beings decided to build an "earth engine" to propel the earth to the constellation Centauri, and finally the earth reached the constellation Centauri.

Centauri C is a red dwarf, also known as Proxima Centauri, located light-years from the Sun and the closest known star to the Sun.

The constellation Centauri (South Gate II) is a triad of star systems, the other two being Centauri A and Centauri B, which are a pair of binary stars located light-years from the Sun. The eccentricity of the orbits of two stars around each other is astronomical units closest to each other (approximately the distance between the Sun and Saturn) and farthest to astronomical units (approximately the distance between the Sun and Pluto) for a period of nearly 80 years.

Centauri: This is a triad that is the closest star to the Sun. This triad is made up of the following three stars:

The ruling planet, Centauri, has the same chemical makeup as the Sun and has the same brightness (magnitude 0).

Dominant star Centauri star B: This star is a companion star of the main star Centauri star A, with magnitude+, located at a distance of arc seconds. The two stars revolve around each other for a period of 8 years.

The main star Centauri C: Also known as Proxima Centauri, it is the third position of the star, 2 degrees southwest from the Earth, and is the closest star (light years) to the Sun, a red dwarf star with a brightness of +

The other 2 are not the closest to Earth.

Centaur is the closest star system to Earth, and the visual triad of stars, of which star A and star B are binary star systems (Alpha centauri ab) at a distance of light years from the sun, and star C is Proxima Centauri light years from the sun.

2 The nearest star to us, the constellation Centauri, is about 10,000 kilometers from Earth; AU; 10,000 light years; Light years ---d).

3 When a light source deviates away from us, the spectral line it emits is shifted to the ( ) of the spectrum.

a.Red end; b.High Frequency End; c.low-end end; d.Purple end ---a).

4 Current observations and calculations indicate that the universe is about ( ) billion light-years; 100 million light years; c.infinity; d.Agnostic---b)5 Current observations and calculations indicate that the age of the universe is about (b) billion years; 100 million years;

c.less than 10 billion years; d.More than 20 billion years.

6 According to the evolutionary history of stars, stars can be broadly divided into ( )astar embryos and main-sequence stars; c.red giants and compact stars;

b are all correct; , b are incorrect.

7 In general, the late stages of stellar evolution become dense astral stars, which include (d)aWhite dwarf; b.Neutron star; c.

Black hole; ,b,c are correct8 According to Titius's formula, there is a planet missing in an orbit in the solar system, but astronomers have found a large number of asteroids in this orbital position, which they call the asteroid belt, which should be distributed between the firewood

3 ac

4 b5 b

6 I don't know that it should be ab right.

7 d8 The Coyper Belt, between Mars and Jupiter.

The day after the great theoretical physicist Stephen Hawking opened Weibo, he used Weibo to announce a bombshell news to Chinese netizens - he will join forces with Russian billionaire Yuri Milner and Facebook founder Mark Zuckerberg to launch a project called "Breakthrough Star", which is committed to developing nano interstellar sailing ships powered by laser beams for space exploration. Their goal is to make the sailboat 20% of the speed of light and reach the closest star system, Centauri, in just about 20 years.

So the question is, what the hell is Centauri? Friends who have read science fiction** Three-Body Problem should know that this is not the nest of the Three-Body Problem! How much do you know about the nest of the Trisolarans? Next, let's take a look at this real-life three-body galaxy.

The world of the three suns

The Centauri galaxy is a three-body galaxy, the so-called three-body galaxy, to put it bluntly, is that this star system has three suns. The three stars are named Centauri A, Centauri B and Centauri C, with A and B being close together to form a binary system, and C being gravitationally linked to this binary system at a distance.

The world of the three suns is a chaotic and terrifying world, and the three-body problem is still an unsolvable mathematical problem, and their laws of motion are irregular, and they cannot be solved accurately. It is precisely based on this that Liu Cixin sketched a world of irregular alternation between the constant era and the chaotic era in "The Three-Body Problem".

How far away is the nearest galaxy to us?

Centauri is the closest star system to our solar system, but it is also more than 4 light-years away. Although 4 light-years is astronomically short, it is an extremely long distance for human civilization at this stage. Using conventional spaceship technology, it would take 30,000 years to reach Centauri.

For a simple comparison, the average distance from the Earth to the Sun is 1 astronomical unit (AU), which is about 100 million kilometers, while the distance from the Sun to Centauri C is as high as 266,750 astronomical units. If Old Man Huo's plan can succeed, then the flying machine will be able to fly to the Trisolar System within a generation, which is definitely a pioneering feat!

A three-body planet in a three-body galaxy

In 2012, researchers at the Harvard-Smithsonian Center for Astrophysics in the United States announced that there may be a planet with a mass similar to that of Earth near Centauri B. This is undoubtedly the three-body planet where the three-body people live, and the three-body civilization has survived countless times of destruction and rebirth here.

However, on November 17, 2015, NASA's Institute for Extraterrestrial Planetary Science brutally took the Trisolarans' lair! They kicked out a number of planets from the database of extrasolar planets that could not be confirmed to really exist, and the three-body planets were unfortunately shot. It seems that we have to wait for Old Man Huo to correct the name of the three-body planet!

Trisolarans, you guys dehydrate first, the human detector will arrive later.

Because it can only adapt to the environment of the southern hemisphere, and in that environment will it grow and develop.

Centauri is one of the southern celestial signs. To observers in the Southern Hemisphere, Centauri is the constellation of autumn evenings, but in China only a few southern provinces can be seen on spring evenings. It is located south of the constellation Hydra, north of the constellation Southern Cross, between the constellations Compass, Jackals and Sails, and its southern part is immersed in the bright Milky Way.

The two brightest stars in the constellation Centauri, the yellow South Gate II and the white Horse Belly One, are very close to each other and very close to the constellation Compass.

The rotation and revolution of the earth have fixed laws and angles. The distant outer planetary systems themselves have less visible light reaching the Earth. In the case of inappropriate angles and the optical action of the atmosphere, some galaxies can indeed be observed within a fixed range of the Earth.

I checked the information for you on the Internet, and here are the ten closest stars to the Earth:

1.Proxima Centauri, light years.

2.Barnard Star, light-years.

3.Woolf 359 stars, light years.

4.Brande 2147 stars, light years.

5.Ewe Cetus, light years.

6.Sirius, light years.

7.Ross 154 stars, light years.

8.Ross 248 stars, light years.

9.Bojiangza anti-three-star, light-year.

10.Ross 128 stars, light years.

A light-year is the speed of light* a year's journey.

Light travels at the speed of light, so the light from Proxima Centauri that we observe today was emitted years ago.

The speed of light c = the distance that light travels in a year, Proxima Centauri is about a light-year away from Earth, so we now see that the light it emits was emitted years ago.

The old mantra – make a man fall in love with you in three days One day, the boy and the girl quarreled. He stopped saying "I love you" to her, and of course she stopped saying "Me too" to him. One night, they talked about breaking up and slept back to back.

In the middle of the night, there was thunder in the sky. At the first thunderclap, he woke up and subconsciously put his hands over her ears, only to realize that he was hugging her again. The thunder followed and pretended nothing had happened, but no one was asleep, and she thought that maybe he still loved me, for fear that I would be a little frightened.

Maybe she still loves me, he thought, or she wouldn't have shed tears. The highest state of love is to withstand the dull passing years. The most beautiful mummy in the world, this is a *** please send to the three forums after receiving the message.

After sending it, you can get your beloved within three days. If you don't send it, you will have bad luck for a month, and the classmate said that he tried it, and it was very smart I don't want it.

299,792,458 meters and seconds is the speed of light, and if it is calculated as 3*10 8m s, the speed of light is 3*10 8 20,000 times the speed of the aircraft.

When it is light, it is in years, and when it is a flying machine.

There are 10,000 years

If a year is calculated as 365 days, one light-year = (

of the 15th power)m. The closest star to the solar system is Proxima Centauri, which is light-years away, and if we take a spacecraft with a speed of 17 km/s, it will take about (years) to travel to Proxima Centauri.