Learn about Hubble Space Telescope

The Hubble Space Telescope, named after American astronomer Edwin Powell Hubble, was first launched into Earth orbit in April 1990.

What is the Hubble telescope?

Hubble Space Telescope (English: Hubble Space Telescope, abbreviated HST) is a NASA telescope, weighing 12 tons, about the size of a bus. It was brought up and operated on Earth's orbit at an altitude of about 610km, about 220km higher than the orbit height of the ISS international space station. At a travel speed of about 7500m / s, Hubble can spin around the Earth for 97 minutes and 15 times a day. Dear Hubble, named after American astronomer Edwin Powell Hubble (1889-1953). This is a reflecting telescope equipped with a computer system and a light-collecting mirror with a diameter of 240cm.

Hubble is fully equipped with solar-powered tools, to capture all the images of the universe with visible light, ultraviolet (UV) and near-infrared wavelengths of light. Of course, all devices on Hubble are designed to operate outside of the Earth's atmosphere and if Hubble is placed on the ground, many devices will no longer work.

Dear Hubble from the Atlantis space shuttle.

History was born

From the 1940s, people began to cook the intention of a space telescope, but it was not until the late 1970s that it was only an idea and a proposal, and most sketches on a desk. Those 30 years spent NASA's huge budget (nearly $ 1 billion) so they asked European partners to provide additional funds to continue the project. In response to that request, the European aerospace agency (ESA) provided NASA with some of Hubble's first equipment along with solar panels. In return, ESA requires them to use Hubble to observe for at least 15% of the time.

However, the Hubble fabrication process did not go smoothly under NASA's plan. Even the infrastructure construction process has to be postponed several times due to problems in the contract. Then, through numerous efforts, in the end of April 1990, Hubble completed and officially launched into orbit from the Canaveral Cape Air Station, USA. However, after reaching the orbit and taking the first photos, scientists quickly realized that for some reason, all the photos were extremely fuzzy, unlike the period. Their initial expectations.

After the investigation period, they finally concluded that the culprit was the optical defect known as "spherical aberration". This is the case that parallel monochromatic light rays passing through non-refracted copper lenses converge at the same point causing the image to lose focus and resolution. "The reason is that the outer edges of the mirror are too flat, its concave is only 4 microns, less than the thickness of a hair," explains Dr. Robert Arentz at the Ball Aerospace group .

Ball Aerospace is the company that supplies most of Hubble's devices and later, they built the Corrective Optics Space Telescope Axial Replacement (COSTAR) - a moving mirror to overcome Hubble's wrong bridge phenomenon. Another good thing is that it has been calculated beforehand that Hubble is designed so that astronauts can repair and upgrade it on orbit. And it is also the only space telescope that can do this. In December 1993, the astronauts approached and attached COSTAR to Hubble.

The process of putting COSTAR into orbit is not a simple thing, the senior director at Ball Aerospace John Troeltzsch recalls: "You have to pack it securely in a box the size of a phone and withstand pressure when launched by shuttle, followed by astronauts walking in space, using robotic arms to mount COSTAR in the correct position with accuracy up to 1/10 mm " .

Hubble telescope activity

The Hubble telescope can capture light from an object 12 billion light-years away. It first uses Microchannel Array Multi-Anode (MAMA) technology to record ultraviolet rays but eliminate light. It has errors in small orientation equivalent to projecting a laser to the right of a coin 320 km away and keeping it that way.

Hubble Space Telescope photo.

Hubble brought many scientific equipment and cameras to analyze the data and capture the images of the universe. These cameras cannot take pictures themselves, but similar to cameras that need lenses, Hubble also needs mirrors to operate. Hubble has a main mirror, about 2.4 meters in diameter and a smaller size mirror.

The light coming from outside to meet the main mirror will reflect to the secondary mirror, then the light will continue to be reflected back to the central position of the main mirror, where there is a hole for light to pass through and lead to the scientific instruments. After that, the camera will record what the reflector system returns with white and black colors. All the colorful lights and colors we often see are due to NASA and the European Aerospace Agency (ESA) synthesizing two or more photos and adding colors.

The design of this glass in modular form allows astronauts to disassemble, replace or repair parts of the parts even though they do not have the expertise of equipment. In one fix, Hubble's resolution was increased by 10.

Important discoveries brought by Hubble

1. Detailed images of all nebulae, especially nebulae, are spreading near spiral galaxies.
2. Pictures of colliding galaxies and quasar galaxies.
3. The first evidence of the presence of black holes.
4. Precise location of dust storms on Mars and more details about the planet's atmosphere
5. Details of the impact of Shoemaker-Levy 9 comet on Jupiter.
6. Detailed storms are thousands of kilometers wide on Uranus.
7. Identify and calculate the expansion of the universe.