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"This photo contains more than 1,000 galaxies, and it looks like the stars are twinkling, it's so beautiful!"
This is the exclamation of American astronomer Eric Welton when he saw the photograph named "Webb's Big Eye".
The image was taken by NASA's Hubble Space Telescope, and its successor, the Webb Telescope, is also known as the "telescope that ate astronomy."
So how powerful is this photo?
How many new perspectives does it give us?
1. The invention of the telescope.
Human curiosity and exploration of the universe began at the beginning of thinking, but due to the limitations of technical conditions, the exploration of the universe has been in a relatively passive state, until the invention of the telescope, which provides favorable conditions for the observation and exploration of the universe.
Although there are many opinions about the inventor of the telescope, many people believe that the inventor of the telescope was Galileo.
Previously, Galileo had been using wooden telescopes to observe various celestial objects in the sky in his daily life, and accumulated a wealth of experience in the process.
In 1609, Galileo Galilei heard that the Dutch merchant Hans Lipsi had invented an optical device called a "telescope" that could magnify the image of a target, so he also thought of using this instrument for astronomical observations.
After many attempts, Galileo finally succeeded in making this telescope into a new astronomical observation tool, and on June 25, 1609, he observed "the mountains of the moon" and "the four moons of Jupiter".
He then presented it to his friends and students, and in August 1609 he presented his inventions and observations to the public in letters.
At this time, people began to gradually learn about this emerging astronomical observation tool, and it was soon valued and used by scholars from all over the world.
Inspired by Galileo, people successively improved and perfected the telescope, and eventually formed a variety of telescopes.
Since then, mankind's exploration of the universe has become wider and wider, and various types of telescopes have emerged, and the greatest telescope is the Hubble Telescope.
The Hubble Telescope is a space telescope launched by NASA in 1990 and is the first real space telescope in human history.
In previous space telescopes, many of them were sent into space by carrying artificial satellites, but the Hubble telescope brought the entire telescope into space, and in 1993, NASA also carried out a maintenance on the Hubble telescope.
The Hubble telescope was the center of attention when it was launched, because it not only had superior observation capabilities, but also unprecedented accuracy in terms of observation.
With the Hubble telescope, we can not only observe galaxies, star clusters, nebulae and other celestial bodies outside the earth, but also study some fundamental properties of the universe, such as black holes, dark matter, dark energy, etc.
At the same time, the Hubble telescope can also help us search for terrestrial planets, observe planetary atmospheres, search for extraterrestrial life, etc.
2. Webb telescope.
Although the Hubble telescope is a great invention, it was launched 30 years ago, so it lacks observation capabilities and its technical level is relatively low.
In the 40 years of development, scientists have made countless improvements and upgrades to the Hubble telescope, and in 2018, NASA launched the successor to the Hubble telescope, the Webb telescope.
The Webb telescope has a more in-depth ability in technology, and its technical level is far beyond the Hubble telescope, which can be said to be another great invention after the Hubble telescope.
The Webb Telescope, also known as the James Webb Space Telescope, is a space telescope jointly developed by NASA and the European Space Agency in 2018 and planned to be launched in 2021.
Compared with the Hubble telescope, the Webb telescope has been improved in all aspects, and the launch of the Webb telescope also cost 9 billion US dollars, so it is also called the "Astronomical Telescope".
The Webb telescope consists of a primary mirror, a solar array, scientific instruments, etc., and its primary mirror is composed of 18 hexagonal lenses, each of which is 2.5 meters long and weighs about 900 kilograms.
These lenses are made of germanium carbide silicon, and their surfaces are coated with a highly reflective aluminium film to improve the reflectivity of the lenses.
In the process of observation, the Webb telescope can not only observe the celestial objects according to the characteristics of light, but also according to the infrared light emitted by the celestial bodies, and at the same time, the primary mirror of the Webb telescope can also adjust the curvature through a micro motor, so as to improve its focusing accuracy.
In addition, the Webb telescope has also designed a huge sunshade device, which is 15 meters long, and its function is to replace the lens tube, which can make the telescope lighter, and can also reduce the difficulty and cost of launching.
The Webb telescope has also been comprehensively upgraded in terms of scientific instruments, which can not only make observations, take pictures, etc., but also conduct spectral analysis, ranging, etc.
At the same time, the Webb telescope is also capable of collecting infrared light, so it can help us observe redshifted galaxies, which can help us study the early days of the universe.
The Webb telescope has also designed a sensor that can be below the freezing point of liquid nitrogen, which is made of indium nitride, and its purpose is to improve the sensitivity of the Webb telescope in observing infrared light, so that it can see redshifted galaxies more clearly.
3. Weber's big eyes.
In 2022, NASA announced that the Webb telescope had completed the assembly of its primary mirror, after scientists had previously used the Hubble telescope to observe Webb's Big Eye.
This photo was taken in 2004, and it is not a photograph, but a photograph of the starry sky made up of more than 1,000 galaxies taken by the Hubble telescope.
In this photo, many galaxies look like twinkling stars, which are really hard to see without looking closely, and it is really spectacular that so many galaxies are clustered together.
This is also unique to the Hubble telescope, which is able to bring together images of galaxies that are difficult to observe.
This photograph is also not a stand-alone photo, but a "Hubble Ultra Deep Space Photo" taken by the Hubble Telescope, which was taken by the Hubble Telescope in 1995 shortly after it took a "Hubble Deep Space Photo" in the middle of 1995.
This "Hubble Ultra Deep Space Photo" was taken in 2003, and in 2004, the Hubble Telescope carried out a comprehensive photo stitching of this "Hubble Super Deep Space Photo", and finally formed this starry sky photo composed of more than 1,000 galaxies.
Most of these galaxies are our Milky Way neighbors, but they are so far away that they are difficult to see with the naked eye.
At the same time, among the more than 1,000 galaxies, there is a small region in the "Hubble Deep Space Field", which is the most special region in this "Hubble Ultra Deep Space Image" because it gathers a large number of galaxies.
epilogue
The Webb telescope, with its "Webb's Big Eye", can deepen its understanding of the universe and has unique advantages in infrared observation, which will also bring us more new perspectives on the universe.