In the process of traveling, Hua Feng sometimes couldn't help but look at the solar system outside the window in a daze, and he didn't know what he could count compared to the solar system in his life......

The position of the solar system in the Milky Way is a very important factor in the development of life on Earth, and its orbit is very close to a circle and maintains about the same speed as the spiral arm, which means that it is almost immobile relative to the spiral arm.

Because the spiral arm is far away from the potentially dangerous supernova dense area, the Earth has been in a stable environment for a long time to develop life. The solar system is also far away from the center of the Milky Way's star-crowded clusters, and near the center, the strong gravitational pull of nearby stars will cause a large number of comets to be sent into the inner solar system, causing collisions with the Earth and endangering developing life.

The intense radiation at the center of the galaxy can also interfere with the complex development of life. Even in the solar system, some scientists believe that debris ejected from supernova explosions that passed through 35,000 years ago, intense radiation towards the Sun, and objects as small as dust as large as comets, once endangered life on Earth.

The Solar Orientation Point (APEX) is the direction in which the Sun moves in interstellar space, near the constellation Hercules, in the direction of the bright Vega Star.

The Solar System is located in the area of the Milky Way where the stars are sparsely scattered and known as the local interstellar cloud. This is an area of interstellar medium shaped like an hourglass, dense with gas and sparse stars, about 300 light-years in diameter, called the bubble of the local galaxy. This bubble is filled with high-temperature plasma that is thought to have been created by some recent supernova explosion.

There are only a handful of stars within 10 light-years (94.6 trillion kilometers) of the Sun, and the closest is the Triad Star, α Centauri, 4.3 light-years away. A and B in the constellation Centauri α are stars that are close together and similar to the Sun, while C (also known as Proxima Centauri) is a small red dwarf star that orbits the pair at a distance of 0.2 light-years.

Next is Barnard 6 light-years away, Wolf-359 at 7.8 light-years, and Laland-21185 at 8.3 light-years. The largest star at a distance of 10 light-years is a blue giant at a distance of 8.6 light-years, Sirius, which is about twice the mass of the Sun and orbited by a white dwarf star (Sirius B). At 10 light-years, there is UV Cetaceid, a two-red dwarf at a distance of 8.7 light-years, and Ross 154, a solitary red dwarf at a distance of 9.7 light-years. The single star similar to the Sun and closest to us is τ Cetus at a distance of 11.9 light-years, with a mass of about 80% of the Sun but only 60% of luminosity.

For thousands of years, until the 17th century, humans did not believe in the existence of the solar system, with a few exceptions. Not only is the Earth considered to be fixed at the center of the universe and immobile, but it is absolutely different from an object or deity that traverses through the ethereal sky.

When Copernicus and his predecessors, like the Indian mathematician and astronomer A

Yabhata and the Greek philosopher A. Aristarchus

ista

Chus), when the structure of the universe was rearranged with the sun as the center, it was still the most forward-looking concept in the 17th century, led by Galileo, Kepler, and Newton, that the reality of the earth not only moving, but also revolving around the sun, and that the planets were governed by the same physical laws that govern the earth, with the same physical and mundane phenomena as the earth: craters, weather, geology, seasons, and polar crowns.

The five planets closest to Earth, Mercury, Venus, Mars, Jupiter, and Saturn, are the five brightest celestial bodies in the sky, known in ancient Greece as planets, meaning wanderers, and have been known to move on celestial spheres with stars as a background, which is where the term comes from.

The first exploration of the solar system was started by telescopes, when astronomers first began mapping these objects, which were invisible to the naked eye due to their dim luminosity.

Galileo was the first astronomer to discover the details of the celestial bodies of the solar system. He discovers the crater of the Moon, the surface of the Sun with sunspots, and Jupiter with 4 moons orbiting. Huygens followed Galileo's discovery and discovered the shape of Saturn's moon Titans and Saturn's rings. Cassini, who succeeded him, discovered 4 moons of Saturn, as well as the Cassini Slit of Saturn's rings and Jupiter's Great Red Spot.

In 1705, Edmund Halley realized that the comet that appeared in 1682 was actually a comet that recurred every 75-76 years, called Halley's Comet. This is the first evidence that a celestial body other than planets revolves around the Sun.

In 1781, William Herschel discovered a conglomerate in the constellation Taurus while observing what he thought was a new comet. In fact, its orbit shows a planet, Uranus, which was the first planet to be discovered.

In 1801, Giusepp Piazzi discovered Ceres, a small world between the orbits of Mars and Jupiter, which he initially thought was a planet. However, the ensuing discoveries brought the number of small objects in this region to tens of thousands, leading them to be reclassified as asteroids.

By 1846, the error in Uranus' orbit led many to wonder if another large planet was exerting force on him from afar. Eban Lévier's calculations eventually led to the discovery of Neptune. In 1859, because Mercury's orbital perihelion had some small movements that Newtonian mechanics could not explain ("Mercury perihelion precession"), some people hypothesized the existence of an underwater planet Zhurong (often translated as "Vulcan in Chinese"); but this movement was eventually proven to be explained by general relativity, but some astronomers still did not give up on the search for "water planets".

In order to explain the apparent deviation in the orbits of the outer planets, Percival Rowell believed that there must be a planet outside of it, which he called Planet X. After his death, its Lowell Observatory continued its search and finally discovered Pluto by Tombeau in 1930. However, Pluto is too small to affect the planet's orbit, so its discovery is purely coincidental. Like Ceres, he was originally considered a planet, but many objects of similar size were found in the adjacent area, so in 2006 Pluto was reclassified as a dwarf planet by the International Astronomical Union.

In 1992, astronomer David Jewett of the University of Hawaii and Jenny Lew of the Massachusetts Institute of Technology discovered 1992 QB1, which proved to be a cold, asteroid-like new group, known as the Kuiper Belt, of which Pluto and Charon were members.

Announced in 2005 by Michael Brown, Chad Trujillo, and David Rabinowitz that Eris is a discrete disk object larger than Pluto and the largest object to orbit the Sun after Neptune.

Since entering the space age, many explorations have been unmanned spacecraft exploration missions organized and carried out by space agencies of various countries.

All the planets in the solar system have been visited by spacecraft launched by the Earth and have been studied to varying degrees. Although they were all unmanned missions, humans were able to view close-up pictures of all the planets' surfaces, and with landing craft, some experiments on soil and atmosphere were conducted.

The first man-made object to go into space was the Soviet Union's Sputnik 1, which successfully circled the Earth for a year. Pioneer 6, launched by the United States in 1959, was the first artificial satellite to send images back from space.

The first to successfully fly by other objects in the solar system was Luna 1, which flew by the Moon in 1959. Originally intended to hit the moon, it missed its target and became the first man-made object to orbit the sun. Mariner 2 was the first man-made object to orbit other planets, orbiting Venus in 1962. The first to successfully orbit Mars was Mariner 4 in 1964. It was not until 1974 that Mariner 10 went to Mercury.

The first spacecraft to explore an outer planet was Pioneer 10, which flew by Jupiter in 1973. In 1979, Pioneer 11 became the first spacecraft to visit Saturn. Voyager planned to launch two spacecraft for a major exoplanet cruise in 1977, Jupiter in 1979, and Saturn in 1980 and 1981. Voyager 2 went on to approach Uranus in 1986 and Neptune in 1989. The Voyager spacecraft has moved far beyond Neptune's orbit and continues on its path to discover and study terminal shockwaves, heliosheaths, and heliopause. According to NASA, two Voyager spacecraft have been exposed to terminal shock waves at a distance of about 93 AU from the Sun.

No spacecraft has ever visited a Kuiper Belt object. New Horizons, launched on January 19, 2006, will be the first man-made spacecraft to explore the region. The unmanned spacecraft is expected to fly past Pluto in 2015. If this proves to be feasible, the mission will be expanded to continue observing some of the other objects in the Kuiper Belt.

In 1966, the Moon became the first solar system object to have an artificial satellite orbit in addition to Earth (Luna 10), followed by Mars in 1971 (Mariner 9), Venus in 1975 (Venera 9), Jupiter in 1995 (Galileo, also in 1991 first flew by Little Gasp).

a), Eros in 2000 (conjunction - Shoemaker), and Saturn in 2004 (Cassini - Huygens).

The Messenger spacecraft is on its way to Mercury and is expected to begin its first orbit around Mercury in 2011, while Dawn will set an orbit around Vesta in 2011 and explore Ceres in 2015.

The first plan to land on other celestial bodies in the solar system was Luna-2, which was launched by the former Soviet Union in 1959. Since then, it has arrived on more and more distant planets, planning to land or impact Venus in 1966 (Venera 3), Mars in 1971 (Mars 3), but it was not until 1976 that Viking 1 successfully landed on Mars, in 2001 it landed on Eros (Rendezvous-Shoemaker), and in 2005 it landed on Saturn's moon Titan (Huygens). In 1995, the Galileo spacecraft also dropped a probe into Jupiter's atmosphere, which was destroyed by the increasing temperature and pressure as Jupiter had no solid surface.

Yuri Gagarin, lifted off on April 12, 1961 aboard Vostok 1. The first to walk on a celestial body other than Earth was Neil Armstrong, who was on the moon on July 21 during the Helios 11 mission in 1969. The U.S. Space Shuttle is the only reusable spacecraft and has completed many missions.

The first space station in orbit was NASA's "Spacelab", which could have multiple crew members and successfully carried three astronauts at the same time between 1973 and 1974. The first real human life in space was the former Soviet Union's Mir space station, which operated in orbit for almost a decade from 1989 to 1999.

It was decommissioned in 2001, and its successor, the International Space Station, has continued to sustain human life in space ever since. In 2004, SpaceShip1 became the first spacecraft to enter sub-orbit with private funding.

In the same year, former U.S. President George W. Bush announced a vision for space exploration: replacing the aging space shuttle, returning to the moon, and even manning Mars.