200 most important Astronomy topics - Sykalo Eugen 2023

The Hubble Space Telescope

The Hubble Space Telescope (HST) is one of the most significant space observatories ever launched. It is named after the astronomer Edwin Hubble, who made some of the most important discoveries in modern astronomy. The HST was launched in 1990 and is still in operation today. In this article, we will explore the history, design, and accomplishments of the Hubble Space Telescope.

History

The concept of a space telescope was first proposed in the 1940s, but it wasn't until the 1970s that NASA and the European Space Agency (ESA) began developing the technology to make it a reality. In 1962, NASA formed a committee called the Space Astronomy Steering Group (SASG) with the goal of studying the feasibility of a space telescope. The SASG concluded that a telescope in space would be able to capture images of the universe that were impossible to obtain from the ground due to atmospheric distortion and absorption.

In 1975, NASA and ESA signed an agreement to collaborate on the project, with NASA providing the telescope and ESA providing the solar panels, instruments, and data processing. The telescope was initially called the Large Space Telescope (LST), but was later renamed the Hubble Space Telescope (HST) in honor of the astronomer Edwin Hubble, who made some of the most important discoveries in modern astronomy.

The HST was designed to be placed in low Earth orbit, where it would be above the Earth's atmosphere and able to capture images of the universe in unprecedented detail. The telescope's primary mirror was 2.4 meters in diameter, which was much larger than any existing ground-based telescope. The mirror was made of ultra-low expansion glass and coated with a thin layer of aluminum. The mirror's shape was designed to correct for spherical aberration, which is a distortion that occurs when light passes through a spherical mirror.

The HST was launched aboard the Space Shuttle Discovery on April 24, 1990. The launch was a major milestone for NASA and ESA, as the telescope had been in development for over 20 years. However, shortly after its deployment, it was discovered that its primary mirror had a flaw that caused images to be fuzzy. This was a major setback for the project, as the telescope was not able to achieve its full scientific potential.

NASA and ESA worked together to develop a solution to the problem, and in 1993, astronauts were able to install a corrective optics system that fixed the problem. The system, called the Corrective Optics Space Telescope Axial Replacement (COSTAR), consisted of a set of corrective optics that could be installed in the telescope's instruments. The installation of COSTAR was a major success, and it allowed the HST to achieve its full scientific potential.

Since then, the HST has been one of the most productive scientific instruments in history. It has made many groundbreaking discoveries, including observing the expansion rate of the universe, which led to the discovery of dark energy, mapping the distribution of dark matter in the universe, observing the formation of stars and planets in distant galaxies, capturing images of the most distant objects in the universe, including galaxies and quasars, observing the atmospheres of planets outside our solar system, and discovering water vapor on one of Jupiter's moons, Europa.

Design

The design of the Hubble Space Telescope is a testament to human ingenuity, collaboration, and innovation. The telescope was designed to be placed in low Earth orbit, where it would be above the Earth's atmosphere and able to capture images of the universe in unprecedented detail. Unlike ground-based telescopes, which are limited by atmospheric distortion and absorption, the HST is able to capture images with incredible clarity and detail.

The HST is a reflecting telescope, which means that it uses mirrors to gather and focus light. It has a primary mirror that is 2.4 meters in diameter and a secondary mirror that reflects the light to the telescope's instruments. The primary mirror is the heart of the telescope, and it is one of the most remarkable pieces of engineering in history. The mirror's size was a major breakthrough, as it was much larger than any existing ground-based telescope. The mirror was made of ultra-low expansion glass and coated with a thin layer of aluminum. The mirror's shape was designed to correct for spherical aberration, which is a distortion that occurs when light passes through a spherical mirror.

The HST's instruments are also a marvel of engineering. The telescope's instruments include cameras, spectrographs, and other sensors that allow astronomers to study the universe in different wavelengths of light, from ultraviolet to infrared. The instruments are housed in a compartment behind the primary mirror, and they are cooled by a heat exchanger to reduce thermal noise.

The HST is powered by solar panels and is in constant motion around the Earth. It orbits at an altitude of about 540 km and completes one orbit every 97 minutes. It travels at a speed of about 28,000 km/h, allowing it to observe any part of the sky for extended periods.

The HST's design has been refined and improved over the years. In 1993, astronauts installed a corrective optics system called the Corrective Optics Space Telescope Axial Replacement (COSTAR). The system consisted of a set of corrective optics that could be installed in the telescope's instruments. The installation of COSTAR was a major success, and it allowed the HST to achieve its full scientific potential.

The HST's design has inspired new space telescopes and has set the stage for future space exploration. The James Webb Space Telescope, which is set to launch in 2021, is the successor to the HST. The JWST will be able to observe the universe in even greater detail than the HST, and it will be able to study the first galaxies that formed after the Big Bang. The HST's design is a testament to human curiosity and the desire to explore the unknown.

Accomplishments

The Hubble Space Telescope has been one of the most productive scientific instruments in history. Since its launch in 1990, the Hubble has made many groundbreaking discoveries that have revolutionized our understanding of the universe and inspired new theories and research. Some of the Hubble's most notable accomplishments include:

One of the Hubble's most significant accomplishments was observing the expansion rate of the universe. In the late 1990s, the Hubble was used to observe supernovae in distant galaxies. These observations revealed that the universe was expanding at an accelerating rate, which suggested the existence of a mysterious force called dark energy. The discovery of dark energy was a major breakthrough in astrophysics, and it has led to new theories and research on the nature of the universe.

The Hubble has also been used to map the distribution of dark matter in the universe. Dark matter is a mysterious substance that makes up about 27% of the universe, but it cannot be directly observed. However, scientists can observe the effects of dark matter on the distribution of galaxies and other cosmic structures. The Hubble has been used to observe the distortion of light caused by the gravity of dark matter, which has allowed scientists to map the distribution of dark matter in the universe.

Another significant accomplishment of the Hubble has been observing the formation of stars and planets in distant galaxies. The Hubble has captured stunning images of galaxies in the process of forming stars and planets. These images have provided valuable insights into the processes that drive star formation and the evolution of galaxies.

The Hubble has also been used to capture images of the most distant objects in the universe, including galaxies and quasars. Some of these objects are billions of light-years away from Earth, and they provide important clues about the early universe and the processes that drove its evolution.

In addition to observing distant objects, the Hubble has also been used to study planets within our own solar system. The Hubble has been used to observe the atmospheres of planets outside our solar system, which has provided valuable insights into the nature of these planets and the conditions that exist on them.