Orion's diamond girdle is set with three brilliant stars, perfectly aligned and spaced; below the girdle, two slightly eclipsed stars are the jewels of his scabbard; and looming in the right tuck is the first magnitude star of Orion's Nebula, Betelgeuse, a massive red star, 20 times larger than the Sun.
Six small stars north of Betelgeuse outline the giant's club; bright and distant Rigel, above Orion's left knee; the star on his right knee is called Saiph; Bellatrix, rests on his left shoulder; a semicircle of stars stretches out by his left arm, when Orion's hand is on the beast.
In a clear viewing picture, O'Dell was surprised to find 110 stars in a small part of the center of the Orion Nebula! Another pancake-shaped cloud surrounded 56 stars, the same disorienting patches that had been seen in past images. O'Dell guessed that there must be more stars in the nebula, escaping the keen sight of astronomical telescopes because they were dimmer than the others around them.
No matter what the explanation for the nebula, there is no doubt that the stars contained within it, along with other stars, are the source of all things. Whether it's the gas molecules in the Orion Nebula, the planets of our solar system, or the trees in our backyards, stars are what create and sustain them.
Like humans, stars are born, mature, age, and die. Exactly what triggers the birth of a star is still a mystery, but it's safe to assume that gravity plays a major role.
When a cloud of gas in a nebula, for some reason, becomes denser and denser relative to the material around it, the cluster will eventually shrink because its own gravity exceeds that of the surrounding material. As the gas cluster continues to be held together by its own gravity, it becomes denser and denser, and the center begins to heat up.
When the center reaches a certain density and temperature, nuclear fusion occurs. A new star is born, a melting pot of hydrogen atoms surrounding a helium cloud woven of gaseous dust. O'Dell and other astronomers have always believed that this swirling, cocoon-like helium cloud is the raw material from which planets form, and that it will eventually dissipate to reveal bright stars.
The color of a star depends on its temperature. Betelgeuse, the first-magnitude star of the Orion Nebula, glows with a reddish halo, and is a low-temperature star, at only 3,000 degrees Celsius. Our Sun, which burns with a yellowish flame, has a temperature of 5,000° Celsius. Some of the hot, massive stars, such as Rigel in Orion, are bluish-white in color and have temperatures of up to 10,000 °C. High-temperature stars rapidly consume energy, converting hydrogen into helium. In the aging stage, the star's composition changes from helium to carbon and from carbon to iron. It becomes reddish in color and massive, and the old, puffy Betelgeuse is at this stage. When the nuclear furnace went out, the star's gravity caused itself to shrink. This sudden contraction is bound to cause a big bang that releases energy, or the birth of a supernova - a fate that will no doubt befall Betelgeuse as well.
When a big bang occurs, if there is a cloud of gas and dust around it, the shock wave compresses a portion of the cloud. The density of the gas cloud increases and another stellar cycle begins.
No other nebula in the spiral embrace of the Milky Way is as vibrant as Orion. Though it's 1,500 light-years away from Earth (a light-year is equivalent to 6 trillion miles), it's clearly visible in the winter night sky.
In 1610, Galileo's telescope was trained on the Orion group outside Padua's window, but for some reason he missed the nebula. In the same year, the Orion Nebula was first discovered by the French lawyer Perisca. He was an amateur astronomer, and interestingly enough, he used a telescope given to him by Galileo. The nebula appears in the telescope in a pearly gray color. Our eyes can only distinguish the brightest part of this nebula, and it does look colorless. At the edges, which we cannot see, is a brilliant red color rendered by drifting helium and hydrogen.
The nebula's main ingredient is hydrogen, but there's also helium, carbon, nitrogen, and oxygen. There are also more than a dozen different molecules, including water and carbon monoxide, which are used to make stars.
The nebula is very irregularly distributed. The intense ultraviolet radiation from the hot stars drives the nebula to expand. Molecular clouds spread rapidly in areas where nebulosity is thin, in much the same way that a prairie wildfire spreads immediately in areas where grass is scarce, but burns slower in brushy areas.
The young Orion Nebula, like a star factory, recreates the birth of the solar system in its early stages of formation. Most of the stars in the Orion Nebula are between 300,000 and a million years old, and compared to our Sun, which is 4.5 billion years old, these stars are like toddlers.
In the center of the nebula are four massive, searing stars arranged in a trapezoidal pattern, the beating heart of the star factory. The largest of these, Theta 1 C, is 20 times the size of the Sun and about 100,000 times brighter, and alone it illuminates the entire nebula. 4 stars that may be less than a million years old, and whose powerful ultraviolet radiation transforms the surrounding nebulosity into a rainbow of colors.
The trapezoidal heart is surrounded by thousands of smaller stars. The richness of the nebula has created the densest and most crowded star cluster in the Milky Way.
By the spring of 1995, scientists had observed the Orion Nebula on four separate occasions using the Hubble Telescope, and ***identified 15 distinct regions. O'Dell spent several weeks piecing together the Hubble views on a computer to produce a complete map of the distribution of the Orion Nebula.
The image shows bright gas clusters edged by curved cloud peaks. This is the final puzzle of the Orion Nebula. The cloud-peak region is turbulent and chaotic, where nebulosity darts around at ultrasonic speeds.
Astronomers believe that the cloud crests are the liminal parts of the early stages of star formation, pushed ever outward by the streams of gas pouring from the center. They form from the magnetic parts of the primordial gas clusters that form stars. When gravity causes the gas cloud to contract, the magnetic part compresses with it, although there is a limit to the compression. When it reaches that limit, the magnetic energy dissipates, prompting the gas particles to move at high speeds along their own paths. The first place where the magnetic energy erupts is the magnetic poles. So by observing the jets the magnetic poles of new stars can be discovered.
The outer space gas and dust around the new star, called the primordial planetary layer, provides strong evidence for the birth of planets.
The "primordial planetary layer" is so called because it contains the ingredients necessary for the formation of planets. The planetary layer is an important part of the puzzle of planet formation.
The concept of a primordial planetary layer confirms the hypothesis made by the astronomer Kuntz in 1755: that planets form in clouds of gas, and that as the nebulosity collapses into a dense, thick core, it gradually gives rise to a new star. The remaining nebulosity swirled around the star and evolved into planets.
Most primordial planetary layers are flat, not spherical. This is due to the speed at which the clouds rotated during the planetary gestation process flattening it out. Some planetary layers look rounded, probably related to the angle of observation, with different angles showing different shapes. Other planetesimals, blown to one side by the strong stellar winds of the Trapezium cluster, resemble a teardrop.
Some primordial planetesimals are much larger than our solar system. One black planetary layer observed by scientists is 7.5 times the diameter of our solar system, while a red star at its center is only 1/3 the size of the sun.
Scientists once thought that only giant star clusters were home to stars, where they were measured in thousands, as if mass-produced. However, using infrared instruments, astronomers have observed a small cloud in the southern part of the Orion Nebula that produces clusters of only 10-50 stars. This is probably how most stars in the Milky Way are born.
Almost all stars have primordial planetary layers outside them, filled with gas and dust. As these stars drift away from their birthplaces, it's possible that galaxies similar to the Sun could form. We still can't prove that there is life in the universe. The vastness of space and the depths of the Milky Way seem to hide countless mysteries, and for the insignificant human being, the exploration is endless. Hubble Space Telescope panoramic view of the Orion Nebula
The Great Nebula in Orion is a bright diffuse nebula with emission lines in the constellation of Orion, in the middle of Orion's Pegasus, just visible to the human eye. The nebula is connected to a star-forming region, illuminated by the young stars it contains, and appears spectacular in astrophotographs. The Great Nebula in Orion is also one of the indicators for recognizing the constellation of Orion; the Great Nebula in Orion is one of the most important objects for astrophotographers and large telescopes of observatories. On September 30, 1880, Henri Draper had already made a successful 15-minute exposure. Draper has successfully photographed the nebula next to the Quadrangle in Orion with an exposure of 15 minutes, and with a fixed exposure of five minutes on a camera with a wide-angle lens he has been able to photograph the whole of the constellation Orion and the Great Nebula in Orion in all its pinkish splendor.
The quadruple star at the center of the nebula is one of the most important targets for observation and study of star birth, and the meticulousness with which the nebula next to it was photographed is a test of astrophotography, telescope resolution, and post-processing efforts. All we need is a pair of binoculars or a small telescope to see M42, and if the conditions are favorable, a five-minute exposure with a wide-angle lens will allow us to capture the pink glow of Orion and the Great Nebula in Orion. The detail of the neighboring nebulae is a test of astrophotography, telescope resolution, and post-processing.
The Great Nebula in Orion, when viewed through ordinary binoculars, already looks like a firebird with its wings outstretched, hence the name "Firebird Nebula", which is not often used