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“Hubble Space Telescope” and its achievements in astronomy



The Hubble Space Telescope, which orbits the Earth, has changed the way astronomers and the general public look at the world. Hubble has exceeded expectations by recording more than 1.4 million observations and providing data for more than 16,000 scientific papers.

“Hubble Space Telescope” and its achievements in astronomy

The idea of building the Hubble Space Telescope was first proposed in the 1940s, but it was in the 1970s that the project gained momentum. NASA began developing the Hubble Space Telescope in the late 1970s, and after several delays, Hubble was finally launched in 1990. The launch of the Hubble Space Telescope was a historic moment for astronomy because it allowed scientists to study the universe in ways that were previously impossible.
Hubble is as big as a bus and weighs as much as two adult elephants. Hubble orbits the Earth at a speed of about five miles per second.
The Hubble Space Telescope is an advanced technology that has been orbiting the Earth since 1990. This telescope is located 347 miles above the Earth’s surface and orbits the planet once every 97 minutes. Its mirror is 2.4 meters in diameter, allowing it to take high-resolution images of distant galaxies, stars, and planets.
The telescope is equipped with a variety of equipment that allows scientists to study the composition, temperature, and other important properties of celestial bodies.
The Hubble telescope works by capturing light from distant objects in the universe. Light from the mirror enters the telescope and is focused on a camera or other equipment. Telescope equipment then analyzes the light to determine its composition, temperature, and other properties. Hubble is also equipped with a system that allows it to adjust its focus and position. This feature is important because it allows scientists to take clear pictures of distant objects. The telescope’s ability to adjust its position allows it to view objects at different angles and provide valuable information about their structure and composition. The Hubble Space Telescope was launched in 1990. Hubble takes pictures of planets, stars and galaxies. This telescope has seen the birth and death of stars. Hubble has seen galaxies that are trillions of miles away from Earth. Also, Hubble has witnessed comet fragments hitting the gases above the planet Jupiter.
The mixture of gases that surround a planet makes up its atmosphere. The earth’s atmosphere changes and prevents the emission of part of the light that arrives from space. Hubble flies around or orbits above the Earth and its atmosphere. Therefore, it can see space better than ground-based telescopes. Hubble uses a digital camera that takes pictures like a cell phone. Hubble then uses radio waves to send pictures from space to Earth.
Hubble is named after Edwin Powell Hubble, an American astronomer who made important discoveries about the universe in the early 1900s. This scientist proved that some elliptical nebulae in the sky are galaxies that are far away from our galaxy.
Hubble Space Telescope
The Hubble Space Telescope has helped scientists learn about the solar system. This telescope shows how galaxies containing billions of stars are formed. Hubble has detected black holes and helped scientists learn more about the explosions that occur when massive stars burn up. Also, the Hubble telescope has been used to study dark matter and dark energy, two of the most mysterious phenomena in the universe. Dark matter and dark energy cannot be observed directly, but their effects can be detected through their gravitational influence on other objects in the universe.
If you’ve ever seen a picture of a spiral galaxy in the background of a computer screen or on the cover of a textbook, chances are it was taken by Hubble. Photos like these highlight the dramatic beauty of our world and are often a great way to inspire science enthusiasts. Hubble images show that science can be more than just combining numbers and codes. These images can reveal spiral galaxies that show where new stars are forming, reminding us that the mystery of galaxy formation is still unsolved. New data from Hubble constantly challenge our preconceived notions about the universe.
Hubble is equipped with a system that allows it to adjust its focus and position. This feature is important because it allows scientists to take clear pictures of distant objects.
Hubble’s main scientific goal was to determine the size and age of the universe. To do this, astronomers measure the change in the brightness of stars called the Cepheid variable. These stars have a variable luminosity that follows a regular pattern, but the frequency of the pattern depends on the actual luminosity of the star. Astronomers use the frequency of this pattern to determine the distance of a galaxy. Hubble’s Large Mirror helped identify Cephasian variable stars at greater distances, and the expansion and age of the universe were confirmed. In addition, this high resolution made it possible to observe more distant supernovae and showed that the expansion of the universe is accelerating. This work completely changed the field of cosmology and won the Nobel Prize in Physics in 2011. This award was given to “Saul Perlmutter”, “Brian Schmidt” and “Adam Riess” for the research “Discovering the accelerated expansion of the universe through the observation of distant supernovae”.
Astronomy is a science that contains many surprises and placing a telescope in space reveals more information. Due to the long life of the Hubble Space Telescope, astronomers have been able to observe unprecedented things such as the movement and changing shape of starbursts over time. Starbursts are caused by gas swirling toward newly formed stars, some of which are driven by magnetic fields, and ejected at extremely high speeds from opposite poles of rotating stars. By examining in the infrared spectrum, these energetic starbursts emitted from young stars can be seen in unparalleled detail. Many observations over time have been invaluable in understanding why these starbursts occur and the environment in which stars are born.

Famous Hubble photos

Over the years, the Hubble Space Telescope has changed the way we see the universe. Its images, based on data sent back by the telescope and through digital image processing, have expanded scientific understanding of everything from the planets of the solar system to dark matter, but Hubble’s contributions go beyond science. Its views of planets, nebulae, galaxies, and star fields have shaped the way we depict and relate to these celestial bodies, making it commonplace to see our world in brilliant color and high definition.
Over the years, the Hubble Space Telescope has changed the way we see the universe. Hubble images have been used as a benchmark for images captured by other telescopes, produced by both world-class scientists and amateur astronomers. These photos have always adorned the walls of science and art museums and even inspired science fiction films. Hubble images encourage us to imagine a dynamic universe full of massive galaxies, ephemeral nebulae, and brilliant star fields that we can see in vivid color, dramatic lighting, and incredibly sharp detail.
1. “Pillars of Creation” is the name of a famous image captured by the Hubble Space Telescope that shows glowing columns of gas and dust against a bright blue background and depicts a star-forming region in the Eagle Nebula. . Its name is derived from the formation of stars in columns of gas and dust.
Hubble Space Telescope
The 1995 image of the Eagle Nebula helped revive the reputation of the Hubble Space Telescope after its initial problems. This photo, released to the public a few months after the telescope was repaired by astronauts, showed that the telescope would live up to expectations. Also, this photo revealed the visual potential of Hubble images. People responded with great enthusiasm, and this enthusiasm helped Hubble produce more images. In particular, it inspired a group of astronomers and image specialists at the Space Telescope Science Institute (STScI) to form the Hubble Heritage Project. Between October 1998 and May 2016, the project released a new aesthetically compelling photo almost every month.
Hubble’s photographs inherit much older traditions of aesthetics. The colors and composition of the Pillars of Creation represent the cosmos as an awe-inspiring heavenly landscape. Yellow-orange columns represent a strange rock set against a sky lit from above by an invisible sun.
2. “Whirlpool Galaxy” (Whirlpool Galaxy) spreads its arms in space like a great spiral staircase. They are actually long paths of stars and gas shrouded in dust. Such arms are a hallmark of large spiral galaxies. In Messier 51 or M51, also known as the Whirlpool Galaxy, these arms serve an important purpose. They are star factories that compress hydrogen gas and form clusters of new stars.
Hubble Space Telescope

“Hubble Space Telescope” and its achievements in astronomy

Some astronomers suspect that the arms of the Whirlpool Galaxy are prominent due to the effects of a close encounter with the dwarf galaxy NGC 5195. The compact galaxy appears to be stretched, creating tidal forces that form new stars. Hubble’s sharp view shows NGC 5195 passing behind M51.
In the fascinating Hubble image of M51, the red color represents infrared light as well as hydrogen in the giant star-forming regions. Blue color can be attributed to hot and young stars; while yellow color indicates older stars.
3. “NGC 4603” (NGC 4603) is a spiral galaxy located in the constellation “Centaurus” at a distance of more than 100 million light years from Earth. In 1999, the Hubble Space Telescope surveyed the galaxy in search of Cephasian variable stars to measure their periodicity. By using the periodicity of 40 identified Kyphousian variables, it is possible to calculate the exact distance from the galaxy.
Hubble Space Telescope
Clusters of bright, young blue stars highlight the galaxy’s spiral arms. In contrast, dying red giant stars are also seen in this image. Even with the Hubble Space Telescope’s unrivaled ability to obtain detailed images of distant objects, only the brightest stars in NGC 4603 can be seen individually. A significant portion of the diffuse glow comes from fainter stars that cannot be detected individually by Hubble. Reddish filaments are regions where dust clouds block blue light from the stars behind them.
This galaxy was observed by the Hubble Space Telescope on a metagalactic scale. Because NGC 4603 was much farther away than the other galaxies that Hubble had studied so far, and its stars appeared very faint from Earth, it was necessary to carefully measure their brightness. This was even more difficult than examining Cephasian variables because at this distance some non-variable stars could appear to be getting brighter and dimmer like Cephasian variables. Determining the distance to the galaxy required an unprecedented statistical analysis based on extensive computer simulations. Observations around distant galaxies like NGC 4603 help astronomers to accurately measure the rate of expansion of the universe.
4. New Horizons mission. Hubble also played a key role in the “New Horizons” mission. From the early 1990s to 2010, Hubble took pictures of the Pluto system in preparation for the New Horizons’ flyby, which was a good thing because Hubble discovered four of Pluto’s moons, and mission scientists used that data to avoid collisions.
After capturing stunning images of Pluto, New Horizons flew past the object known as Ultima Thuli (Arrokoth) in the Kuiper Belt, discovered by Hubble. Without the Hubble Space Telescope, we would never have been able to see this strange object and the mission would have ended much earlier.
5. “Hubble Deep Field” One of the famous pictures of the Hubble Space Telescope is called “Hubble Deep Field”. The telescope pointed its camera at a part of the sky that seemed virtually empty in all previous observations. Hubble then left the shutter open for 10 days and collected all the light from a seemingly empty part of space. Using long exposures, just like traditional cameras on Earth, astronomers were able to see what was hidden in the dark. This photo showed 3,000 galaxies, several hundred of which had not been seen before.
Hubble Space Telescope

The result of this work was wonderful. So, the astronomers did it again and took pictures of the Hubble Ultra Deep Field and the Hubble Extreme Deep Field. They did it each time using longer exposures and improved equipment.

6. “NGC 6302” or “Butterfly Nebula” is one of the nebulae photographed by Hubble. With a surface temperature estimated at around 250,000 degrees Celsius, the dying central star of the nebula is extremely hot and glows in ultraviolet light, but is obscured from direct view by a dense mass of dust. A close-up and colorful view of the Butterfly Nebula was captured in 2009 by the Hubble Space Telescope’s Wide Field Camera 3. The dust cloud surrounding the central star lies within a bright hole of ionized gas near the center of the view. Molecular hydrogen has been detected in the dusty cosmic mantle of a hot star.

Hubble Space Telescope

The Butterfly Nebula is located at a distance of 4000 light years from Earth in the constellation of “Scorpius”. The butterfly nebula shows what happens at the end of a star’s life after its gas and dust run out. This is not only a reminder of the ultimate fate of our own Sun and Solar System but also sheds light on Hubble’s unique ability to observe this event over the long life cycle of a star and study how stars evolve.

7. The galaxy “UGC 10214” or “Tadpole Galaxy” is only 420 million light years away from the face of “Draco”. The frog’s tail is about 280,000 light-years long and shows large and bright star clusters in blue. In a stunning image captured by the Hubble Space Telescope’s Advanced Camera, distant galaxies form a backdrop to the Spiral Galaxy Frog. The Toadstool galaxy is disrupted by collisions and shows bursts of star formation in its tail, but behind it are thousands of other galaxies. This picture shows the power of Hubble.

Hubble Space Telescope

8. The star cluster “NGC 602” (NGC 602) is located near the outskirts of the Small Magellanic Cloud, at a distance of about 200 thousand light years from Earth. Surrounded by natural gas and dust, NGC 602 shows itself in this Hubble image. In star clusters like NGC 602, you can see the star-birth region. The extraordinary bulges and wavy shapes show that energetic radiation and shock waves from the massive young star NGC 602 have eroded the dusty material away from the center of the star cluster. A surprising array of background galaxies are also visible in the Hubble image. The background galaxies are hundreds of million light-years or more away from NGC 602.

Hubble Space Telescope

Using Hubble observations, it was confirmed that the stars of NGC 602 were not born suddenly, but formed at different times. Hubble also determined that star formation may have begun there as early as 60 million years ago.

9. Galaxy “NGC 1300” (NGC 1300). One of the largest Hubble Space Telescope images of an entire galaxy is NGC 1300. This galaxy is an amazing example of a barred spiral galaxy. Unlike other spiral galaxies, whose stellar arms extend outward from the center, NGC 1300’s arms radiate away from the end of a straight band of stars that extends across the galactic core.

Hubble Space Telescope

“Hubble Space Telescope” and its achievements for astronomy Using Hubble to study more than 2,000 nearby and far-off spiral galaxies, astronomers found that barred spiral galaxies are more common today than in the past. In this image, the Hubble telescope captured a display of starlight, glowing gas, and dark clouds of interstellar dust.
NGC 1300 is a prototype of spiral bar galaxies, which has a very beautiful shape and interesting color. Beyond that, if we look closely at its depth, we can see galaxies that are much further away.
10. The “Rat Galaxies” or “NGC 4676” are a spectacular pair of galaxies that appear as two mice in a galactic dance. These galaxies, which are located at a distance of 300 million light years from Earth, are located in the constellation “Coma Berenices” and are called mice because of the long trails of stars and gases emitted from each galaxy. The Hubble Space Telescope image shows the most detail and the most stars ever seen in these galaxies. The bright blue part in the left galaxy shows a strong cascade of young, hot blue stars formed by the interaction of tidal forces. Also, in this photo you can see streams of material moving between these two galaxies. Hubble has revealed stunning details in the tails of rats.
Hubble Space Telescope
11. The Helix Nebula or NGC 7293 is a bright and large tubular planetary nebula located 650 light-years from Earth in the constellation Aquarius. This nebula is actually a shell of expanding gas around a dying star. Shells ejected by dying stars are condensed into gas masses. This means they go into the interstellar medium.
Hubble Space Telescope
The Spiral Nebula is one of the closest planetary nebulae to Earth and one of the brightest nebulae, which is also called the “God’s Eye Nebula” because of its appearance.
This image taken by the Hubble Space Telescope, staring directly into the tubular nebula, shows its appearance well and provides general information about how the planetary nebula formed. This composite image shows a colorful spiral nebula covered in glowing gas.
12. Jupiter’s aurora borealis. The Hubble Space Telescope is a good choice for studying auroras on Jupiter. Jupiter is the largest planet in the solar system and is best known for its colorful storms, the most famous of which is the Great Red Spot. Using Hubble’s ultraviolet capabilities, astronomers focused on another beautiful feature of the planet Jupiter.
Hubble Space Telescope
One of the most beautiful pictures taken by Hubble of the solar system is this view of Jupiter’s aurora borealis. The vivid and extraordinary glows shown in this photo are known as auroras. They form when energetic particles enter the planet’s atmosphere near its magnetic poles and collide with gas atoms. To highlight changes in the auroras, Hubble observed Jupiter almost every day for several months.
Auroras are not only huge in size, they are hundreds of times more energetic than terrestrial auroras, and unlike their counterparts on Earth, they never stop. Hubble’s observations help to better understand how the Sun and other energy sources affect the auroras.

Future plans

Hubble has lasted more years than expected and completed many space missions, but it will surely be retired one day. Hubble is not the only space telescope in operation. Several other telescopes are currently operating or under development, the most important of which are the James Webb Space Telescope (JWST) and the Wide Field Infrared Survey Probe (WFIRST). Both telescopes have very advanced camera technology. Plus, they have larger mirrors that can collect more light. Together, they cover the wavelength range that Hubble has worked in, and possibly beyond.


Black holes may be the source of mysterious dark energy




black holes
The expansion of black holes in the universe can be a sign of the presence of dark energy at the center of these cosmic giants. The force that drives the growth of the world.

Black holes may be the source of mysterious dark energy


According to new research, supermassive black holes may carry the engines driving the universe’s expansion or mysterious dark energy. The existence of dark energy has been proven based on the observation of stars and galaxies, but so far no one has been able to find out its nature and source.

The familiar matter around us makes up only 5% of everything in the universe. The remaining 27% of the universe is made up of dark matter, which does not absorb or emit any light. On the other hand, a large part of the universe, or nearly 68% of it consists of dark energy.

According to new evidence, black holes may be the source of dark energy that is accelerating the expansion of the universe. This research is the result of the work of 17 astronomers in nine countries, which was conducted under the supervision of the University of Hawaii. British researchers from Raleigh Space, England’s Open University, and King’s College London collaborated in this research.

Black hole accretion pillAn artist’s rendering of a supermassive black hole complete with a fiery accretion disk.

By comparing supermassive black holes spanning 9 billion years of the universe’s history, researchers have found a clue that the greedy giant objects at the heart of most galaxies could be the source of dark energy. The articles of this research were published in The Astrophysical Journal and The Astrophysical Journal Letters on February 2 and 15. Chris Pearson, one of the authors of the study and an astrophysicist at the Appleton Rutherford Laboratory (RAL) in the UK says:

If the theory of this research is correct, it could revolutionize the whole of cosmology, because at least we have found a solution to the origin of dark energy, which has puzzled cosmologists and theoretical physicists for more than twenty years.

The theory that black holes can carry something called vacuum energy (an embodiment of dark energy) is not new, and the discussion of its theory actually goes back to the 1960s; But the new research assumes that dark energy (and therefore the mass of black holes) increases over time as the universe expands. Researchers have shown how much of the universe’s dark energy can be attributed to this process. According to the findings, black holes could hold the answer to the total amount of dark energy in the current universe. The result of this puzzle can solve one of the most fundamental problems of modern cosmology.

Rapid expansion

Our universe began with the Big Bang about 13.7 billion years ago. The energy from this explosion of space once caused the universe to expand so rapidly that all the galaxies were moving away from each other at breakneck speed. However, astronomers expected the rate of this expansion to slow down due to the gravitational influence of all the matter in the universe. This attitude toward the world prevailed until the 1990s; That is when the Hubble Space Telescope made a strange discovery. Observations of distant exploding stars have shown that in the past the universe was expanding at a slower rate than it is now.

Therefore, contrary to the previous idea, not only the expansion of the universe has not slowed down due to gravity, but it is increasing and speeding up. This result was very unexpected and astronomers sought to justify it. Thus, it was assumed that “dark energy” pushes objects away from each other with great power. The concept of dark energy was very similar to a cosmic constant proposed by Albert Einstein that opposes gravity and prevents the universe from collapsing but was later rejected.

Stellar explosions

But what exactly is dark energy? The answer to this question seems to lie in another cosmic mystery: black holes. Black holes are usually born when massive stars explode and die. The gravity and pressure in these intense explosions compress a large amount of material into a small space. For example, a star roughly the same mass as the Sun can be compressed into a space of only a few tens of kilometers.

The gravitational pull of a black hole is so strong that even light cannot escape it and everything is attracted to it. At the center of the black hole is a space called singularity, where matter reaches the point of infinite density. The point is that singularities should not exist in nature.

Speed ​​up dark energyDark energy explains why the universe is expanding at an accelerating rate.

Black holes at the center of galaxies are much more massive than black holes from the death of stars. The mass of galactic “massive” black holes can reach millions to billions of times the mass of the Sun. All black holes increase in size by accreting matter and swallowing nearby stars or merging with other black holes; Therefore, we expect these objects to become larger as they age. In the latest paper, researchers investigated the supermassive black holes at the centers of galaxies and found that the mass of these objects has increased over billions of years.

Fundamental revision

The researchers compared the past and present observations of elliptical galaxies that lack the star formation process. These dead galaxies have used up all their fuel, and as a result, their increase in the number of black holes over time cannot be attributed to normal processes that involve the growth of black holes by accreting matter.

Instead, the researchers suggested that these black holes actually carry vacuum energy, which has a direct relationship with the expansion of the universe, so as the universe expands, their mass also increases.

Black hole visualizationVisualization of a black hole that could play a fundamental role in dark energy.

Revealing dark energy

Two groups of researchers compared the mass of black holes at the center of two sets of galaxies. They were a young, distant cluster of galaxies with lights originating nine billion years ago, while the closer, older group was only a few million light-years away. Astronomers found that supermassive black holes have grown between seven and twenty times larger than before so this growth cannot be explained simply by swallowing stars or colliding and merging with other black holes.

As a result, it was hypothesized that black holes are probably growing along with the universe, and with a type of hypothetical energy known as dark energy or vacuum that leads to their expansion, they overcome the forces of light absorption and destruction of the stars in their center.

If dark energy is expanding inside the core of black holes, it can solve two long-standing puzzles of Einstein’s general relativity; A theory that shows how gravity affects the universe on massive scales. The new finding firstly proves how the universe does not fall apart due to the overwhelming force of gravity, and secondly, it eliminates the need for singularities (points of infinity where the laws of physics are violated) to describe the workings of the dark heart of black holes.

To confirm their findings, astronomers need more observations of the mass of black holes over time, and at the same time, they need to examine the increase in mass as the universe expands.

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Scientists’ understanding of dark energy may be completely wrong




dark energy
The standard model of cosmology says that the strength of dark energy should be constant, But inconclusive findings suggest that this force may have weakened.

Scientists’ understanding of dark energy may be completely wrong

On April 4th, astronomers who created the largest and most detailed 3D map ever made of the universe announced that they may have found a major flaw in their understanding of dark energy, the mysterious force driving the universe’s expansion.

Dark energy has been postulated as a stable force in the universe, both in the current era and throughout the history of the universe; But new data suggests that dark energy may be more variable, getting stronger or weaker over time, reversing or even disappearing.

Adam Reiss, an astronomer at Johns Hopkins University and the Space Telescope Science Institute in Baltimore, who was not involved in the new study, was quoted by the New York Times as saying, “The new finding may be the first real clue we’ve had in 25 years about the nature of dark energy.” In 2011, Reiss won the Nobel Prize in Physics along with two other astronomers for the discovery of dark energy.

The recent conclusion, if confirmed, could save astronomers and other scientists from predicting the ultimate fate of the universe. If the dark energy has a constant effect over time, it will eventually push all the stars and galaxies away from each other so much that even the atoms may disintegrate and the universe and all life in it, light, and energy will be destroyed forever. Instead, it appears that dark energy can change course and steer the universe toward a more fruitful future.

Dark energy may become stronger or weaker, reverse or even disappear over time

However, nothing is certain. The new finding has about a 1 in 400 chance of being a statistical coincidence. More precisely, the degree of certainty of a new discovery is three sigma, which is much lower than the gold standard for scientific discoveries called five sigma or one in 1.7 million. In the history of physics, even five-sigma events have been discredited when more data or better interpretations have emerged.

The recent discovery is considered an initial report and has been published as a series of articles by the group responsible for an international project called “Dark Energy Spectroscopy Instrument” or DESI for short. The group has just begun a five-year effort to create a three-dimensional map of the positions and velocities of 40 million galaxies over the 11 billion-year history of the universe. The researchers made their initial map based on the first year of observations of just six million galaxies. The results were presented April 4 at the American Physical Society meeting in Sacramento, California, and at a conference in Italy.

“So far we’re seeing initial consistency with our best model of the universe,” DESI director Michael Levy said in a statement released by Lawrence Berkeley National Laboratory, the center overseeing the project. “But we also see some potentially interesting differences that may indicate the evolution of dark energy over time.”

“The DESI team didn’t expect to find the treasure so soon,” Natalie Palanque-Delaberville, an astrophysicist at Lawrence Berkeley Lab and project spokeswoman, said in an interview. The first year’s results were designed solely to confirm what we already knew. “We thought we would basically approve the standard model.” But the unknowns appeared before the eyes of the researchers.

The researchers’ new map is not fully compatible with the standard model

When the scientists combined their map with other cosmological data, they were surprised to find that it didn’t completely fit the Standard Model. This model assumes that dark energy is stable and unchanging; While variable dark energy fits the new data. However, Dr. Palanque-Delaberville sees the new discovery as an interesting clue that has not yet turned into definitive proof.

University of Chicago astrophysicist Wendy Friedman, who led the scientific effort to measure the expansion of the universe, described the team’s results as “tremendous findings that have the potential to open a new window into understanding dark energy.” As the dominant force in the universe, dark energy remains the greatest mystery in cosmology.

Imaging the passage of quasar light through intergalactic clouds
Artistic rendering of quasar light passing through intergalactic clouds of hydrogen gas. This light provides clues to the structure of the distant universe.
NOIRLab/NSF/AURA/P. Marenfeld and DESI collaboration

The idea of ​​dark energy was proposed in 1998; When two competing groups of astronomers, including Dr. Rees, discovered that the rate of expansion of the universe was increasing rather than decreasing, contrary to what most scientists expected. Early observations seemed to show that dark energy behaved just like the famous ” fudge factor ” denoted by the Greek letter lambda. Albert Einstein included lambda in his equations to explain why the universe does not collapse due to its own gravity; But later he called this action his biggest mistake.

However, Einstein probably judged too soon. Lambda, as formulated by Einstein, was a property of space itself: as the universe expands, the more space there is, the more dark energy there is, which pushes ever harder, eventually leading to an unbridled, lightless future.

Dark energy was placed in the standard model called LCDM, consisting of 70% dark energy (lambda), 25% cold dark matter (a collection of low-speed alien particles), and 5% atomic matter. Although this model has now been discredited by the James Webb Space Telescope , it still holds its validity. However, what if dark energy is not as stable as the cosmological model assumes?

The problem is related to a parameter called w, a special measure for measuring the density or intensity of dark energy. In Einstein’s version of dark energy, the value of this parameter remains constant negative one throughout the life of the universe. Cosmologists have used this value in their models for the past 25 years.

Albert Einstein included lambda in his equations to explain why the universe is collapsing under its own gravity.

But Einstein’s hypothesis of dark energy is only the simplest version. “With the Desi project we now have the precision that allows us to go beyond that simple model to see if the dark energy density is constant over time or if it fluctuates and evolves over time,” says Dr. Palanque-Delabreville.

The Desi project, 14 years in the making, is designed to test the stability of this energy by measuring the expansion rate of the universe at different times in the past. In order to do this, scientists equipped one of the telescopes of the Keith Peak National Observatory in Arizona, USA, with five thousand optical fiber detectors that can perform spectroscopy on a large number of galaxies at the same time to find out how fast they are moving away from Earth.

The researchers used fluctuations in the cosmic distribution of galaxies, known as baryonic acoustic variations , as a measure of distance. The sound waves in the hot plasma accumulated in the universe, when it was only 380,000 years old, carved the oscillations on the universe. At that time, the oscillations were half a million light years across. 13.5 billion years later, the universe has expanded a thousandfold, and the oscillations, now 500 million light-years across, serve as convenient rulers for cosmic measurements.

Desi scientists divided the last 11 billion years of the universe into 7 time periods and measured the size of the fluctuations and the speed of the galaxies in them moving away from us and from each other. When the researchers put all the data together, they found that the assumption that dark energy is constant does not explain the expansion of the universe. Galaxies appeared closer than they should be in the last three periods; An observation that suggests dark energy may be evolving over time.

“We’re actually seeing a clue that the properties of dark energy don’t fit a simple cosmological constant, and instead may have some deviations,” says Dr. Palanque-Delaberville. However, he believes that the new finding is too weak and is not considered proof yet. Time and more data will determine the fate of dark energy and the researchers’ tested model.

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Why the James Webb telescope does not observe the beginning of the universe?




James Webb telescope

The James Webb Space Telescope is one of the most advanced telescopes ever built. Planning to launch James Webb began more than 25 years ago, and construction efforts took more than a decade. On December 25, 2021, this telescope was launched into space and within a month it reached its final destination, 930,000 miles away from Earth. Its position in space gives it a relatively unobstructed view of the world.

Why the “James Webb” telescope does not observe the beginning of the universe?

The design of this telescope was a global effort led by NASA and aims to push the boundaries of astronomical observation with revolutionary engineering. Its mirror is huge, about 21 feet (6.5 meters) in diameter, which is about three times the size of the Hubble Space Telescope, which was launched in 1990 and is still operating.

According to SF, it’s the telescope’s mirror that allows it to gather light. James Webb is so big that it can see the faintest and most distant galaxies and stars in the universe. Its advanced instruments can reveal information about the composition, temperature, and motion of these distant cosmic bodies.

Astrophysicists constantly look back to see what stars, galaxies, and supermassive black holes looked like when their light began its journey toward Earth, and use this information to better understand their growth and evolution. For the space scientist, the James Webb Space Telescope is a window into that unknown world. How far can James Webb look into the universe and its past? The answer is about 13.5 billion years.

Time travel

A telescope does not show stars, galaxies, and exoplanets as they are. Instead, astrologers have a glimpse of how they were in the past. It takes time for light to travel through space and reach our telescope. In essence, this means that looking into space is also a journey into the past.

This is true even for objects that are quite close to us. The light you see from the sun has left about eight minutes and 20 seconds earlier. This is how long it takes for sunlight to reach the earth.

You can easily do calculations on this. All light, whether it’s sunlight, a flashlight, or a light bulb in your home, travels at a speed of 186,000 miles (approximately 300,000 kilometers) per second. This is more than 11 million miles, which is about 18 million kilometers per minute. The sun is about 93 million miles (150 million kilometers) from the earth. which brings the time of reaching the light to about eight minutes and 20 seconds.

Why the “James Webb” telescope does not observe the moment of the beginning of the universe?

But the farther something is, the longer it takes for its light to reach us. That’s why the light we see from the closest star to us other than the Sun, Proxima Centauri, dates back four years. This star is about 25 trillion miles (about 40 trillion kilometers) from Earth, so it takes a little over four years for its light to reach us.

Recently, James Webb has observed the star Earendel, which is one of the most distant stars ever discovered and the light that James Webb sees is about 12.9 billion years old.

The James Webb Space Telescope travels much further into the past than other telescopes such as the Hubble Space Telescope. For example, although Hubble can see objects 60,000 times fainter than the human eye, James Webb can see objects almost 9 times fainter than even Hubble.

Read more: How can solar storms destroy satellites so easily?

Big Bang

But is it possible to go back to the beginning of time?

Big Bang is the term used to define the beginning of the universe as we know it. Scientists believe that this happened about 13.8 billion years ago. This theory is the most accepted theory among physicists to explain the history of our universe.

However, the name is a bit misleading because it suggests that some kind of explosion, like a firework, created the universe. The Big Bang more accurately represents space that is rapidly expanding everywhere in the universe. The environment immediately after the Big Bang resembled a cosmic fog that covered the universe and made it difficult for light to pass through. Eventually, galaxies, stars, and planets began to grow.

That’s why this period is called the “Cosmic Dark Age” in the world. As the universe continued to expand, the cosmic fog began to lift and light was finally able to travel freely through space. In fact, few satellites have observed the light left over from the Big Bang some 380,000 years after it happened. These telescopes are designed to detect the glow left over from the nebula, whose light can be traced in the microwave band.

However, even 380,000 years after the Big Bang, there were no stars or galaxies. The world was still a very dark place. The cosmic dark ages did not end until several hundred million years later when the first stars and galaxies began to form.

The James Webb Space Telescope was not designed to observe the time to the moment of the Big Bang, but to see the period when the first objects in the universe began to form and emit light.

Before this time period, due to the conditions of the early universe and the lack of galaxies and stars, there was little light for the James Webb Space Telescope to observe.

By studying ancient galaxies, scientists hope to understand the unique conditions of the early universe and gain insight into the processes that helped them flourish. This includes the evolution of supermassive black holes, the life cycles of stars, and what exoplanets are made of.

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