The Hubble Space Telescope is one of the most iconic instruments in modern astronomy. Positioned outside Earth's atmosphere, this telescope was designed to observe the depths of the universe and provide humanity with unique images.

^{Hubble Space Telescope, February 1997. [1]}

History

The idea of the Hubble Space Telescope dates back to the early 20th century. In 1923, German scientist Hermann Oberth proposed the concept of placing a telescope in space. However, the idea was postponed until the 1970s, when NASA and the European Space Agency (ESA) seriously considered it. The telescope is named after American astronomer Edwin Hubble, who discovered the expansion of galaxies, providing crucial evidence for the expansion of the universe.

Positioned outside Earth's atmosphere, the telescope has several advantages over ground-based telescopes. It can capture clear images without the distortions caused by the atmosphere (such as blurring and noise) and observe ultraviolet light that is blocked by the ozone layer.

After its launch in 1990, it became one of the most important tools in the history of astronomy. It has greatly contributed to solving fundamental problems in astrophysics. The Hubble Ultra Deep Field image, captured by the telescope, is the most detailed visible-light image of the farthest reaches of the universe ever taken.

^{Hubble Ultra Deep Field. Created by combining data collected by the Hubble Space Telescope from September 24, 2003, to January 16, 2004. [2]}

Hubble completes 15 orbits around Earth each day, circling the planet approximately every 95 minutes. The observatory moves at a speed of about 5 miles per second (8 km/s), fast enough to cross the United States in about 10 minutes. As Hubble orbits, its primary mirror collects light from near and distant objects. Its primary mirror, about 8 feet (2.4 meters) in diameter, is smaller than those of many professional observatories on Earth. What makes Hubble so powerful is its position above Earth's atmosphere, which provides an unobstructed view of the universe and allows it to observe wavelengths that are blocked or partially filtered by the atmosphere. Hubble can resolve objects 1,000 times better than the human eye. This is roughly equivalent to seeing two fireflies separated by 10 feet (3 meters) from a distance of 7,000 miles (11,000 kilometers) between New York City and Tokyo.

^{360-degree tour video of the Hubble Space Telescope. [3]}

Design

Hubble is the first space-based observatory specifically designed for servicing while in orbit. Its precise optical design allows it to see objects 10 billion times fainter than the human eye can detect—it can distinguish two fireflies 10 feet apart from 7,000 miles away. Its gyroscopes are so sensitive that they could keep a laser pointed at a president's head 200 miles away for 24 hours. Its fine guidance sensors are so precise that they can keep a laser pointed at a human hair a mile away for 24 hours while the telescope orbits Earth at over 17,000 miles per hour (27,000 kph).

The Hubble Space Telescope is positioned in low Earth orbit, approximately 547 kilometers above Earth's surface. This altitude allows it to capture clear images without atmospheric distortion. Its key features include:

• Mirror Diameter: 2.4 meters
• Weight: 11,110 kilograms
• Power Source: Solar panels
• Imaging Instruments: Wide Field Camera 3 (WFC3), Near Infrared Camera and Multi-Object Spectrometer (NICMOS), Cosmic Origins Spectrograph (COS), and others.

Hubble can observe in the ultraviolet, visible, and infrared regions of the electromagnetic spectrum, enabling the study of the universe at different wavelengths.

Applications

• Galaxies and the Expansion of the Universe: Hubble has observed the motion of galaxies to measure the rate of the universe's expansion, providing evidence for dark energy.
• Black Holes: Hubble has confirmed the existence of supermassive black holes at the centers of galaxies and studied their effects.
• Star Formation Regions: The telescope has captured detailed images of nebulae where stars are born. The "Pillars of Creation" in the Eagle Nebula is one of Hubble's most famous images.
• Planets and Exoplanets: Hubble has studied the atmospheres of planets in our solar system and contributed to the discovery of exoplanets.
• Cosmic Distance Measurements: Using Cepheid variable stars, Hubble has measured distances between galaxies and estimated the age of the universe.

Contributions to Science

The Hubble Space Telescope has been a turning point in the history of astronomy. Its data has been the basis for over 18,000 scientific papers. The telescope has calculated the age of the universe to be approximately 13.8 billion years and has led research into mysterious concepts like dark energy. Additionally, Hubble's stunning images have increased public interest in astronomy and inspired curiosity about science.

^{The evolution of Saturn's rings captured by the Hubble Space Telescope between 2018 and 2024. [4]}

^{Some of the images collected by the telescope over the last 30 years. [5]}

^{Hubble's decade-long imaging of exoplanets. [6]}