Hubble Telescope: A Journey Through Decades and Discoveries

Hubble Space Telescope: A Journey Through Three Decades of Revolutionary Discoveries

Introduction

Since its launch on April 24, 1990, NASA's Hubble Space Telescope, in collaboration with the European Space Agency (ESA), has fundamentally changed our understanding of the universe. The telescope orbits at an altitude of 515 kilometers above the Earth, away from atmospheric distortions, granting it exceptional clarity in observing the universe across multiple wavelengths. Over 34 years, its observations have surpassed one million and contributed to the publication of more than 21,000 scientific studies. This article reviews Hubble's most significant achievements, detailing how each discovery has reshaped astronomy.

Hubble Telescope: A Journey Through Decades and Discoveries

 Unraveling the Secrets of the Expanding Universe 

Measuring the Cosmic Expansion Rate (Hubble's Constant)

In the 1990s, Hubble led a massive project to measure the "Hubble Constant," which determines the rate of cosmic expansion. By using Cepheid variable stars as standard candles, Hubble improved the measurement accuracy by 10%, revealing the acceleration of expansion due to dark energy, a discovery that won the Nobel Prize in 2011.

Elements of the Early Universe

Hubble observed distant galaxies whose light has traveled for billions of years, uncovering concentrations of light elements such as hydrogen and helium, thereby confirming Big Bang theories regarding the formation of the first elements.

Farthest Galaxy and Star

In 2016, Hubble observed the galaxy GN-z11, which formed 400 million years after the Big Bang. In 2022, it captured an image of the star Earendel, which dates back to 900 million years after the universe's inception, leveraging gravitational lensing.

The Fate of the Milky Way Galaxy

Hubble confirmed that the Andromeda galaxy is moving toward us at a speed of 110 km/s, with a collision expected in 4.5 billion years, forming a giant galaxy.

 Black Holes: From Fiction to Reality

First Confirmation of Supermassive Black Holes

In 1994, Hubble observed the rapid motion of stars around the center of the galaxy M87, proving the existence of a supermassive black hole with a mass of 6.5 billion suns. These observations paved the way for capturing the first image of a black hole's shadow in 2019.

Black Holes at the Center of Galaxies

Hubble studies have shown that most galaxies, like the Milky Way, contain supermassive black holes at their centers, linking galaxy evolution to these cosmic monsters.

 Exoplanets: From Science Fiction to Reality

First Exoplanet Atmosphere

In 2001, Hubble analyzed the atmosphere of the exoplanet HD 209458 b and discovered sodium, marking the first chemical analysis of a world outside the solar system.

Evaporating Atmosphere

Hubble observed the same planet losing its atmosphere at a rate of 35,000 km/h, revealing the effect of stellar radiation on nearby planets.

Organic Molecules and Water Suitable for Life

In 2008, Hubble discovered methane and carbon dioxide in the atmosphere of  HD 189733 b , while in 2019, it observed water vapor on K2-18b, the first planet in the "habitable zone."

Potential Exoplanet Moon

In 2018, Hubble detected signals of a moon orbiting the planet Kepler-1625b, potentially opening doors to the study of Earth-like planetary systems.

 Our Solar System: New Worlds Awaiting Exploration

Water Plumes on Europa

In 2013, Hubble observed water vapor plumes erupting from Jupiter's moon Europa, indicating an ocean beneath its icy surface, supporting the possibility of life.

Asteroid Debris and Tails

In 2010, Hubble imaged the asteroid P/2010 A2, showing tails formed from its collision with another body, providing visual evidence of the violent dynamics of the asteroid belt.

First Images of Another Star's Surface

In the 1990s, Hubble's images of the star Betelgeuse revealed massive thermal spots, giving the first glimpse of a star's surface outside the solar system.

 Stellar Phenomena: From Birth to Death

The Anticipated Supernova

In 2015, Hubble captured an image of the supernova Refsdal, predicted to appear due to gravitational lensing effects, confirming the strength of astronomical theories.

Planetary Formation Disks

Hubble observed dusty disks around young stars in the Orion Nebula, where planets form, showcasing the process of birth of planetary systems.

 Hubble's Techniques: Eyes Above the Atmosphere

Hubble possessed unique features thanks to its orbital location and advanced instruments, such as:

- The Wide Field Camera 3 (WFC3) that enabled the observation of distant galaxies.

- The ultraviolet spectrograph that analyzed the atmospheres of planets.

- The ability to conduct multi-wavelength observations from ultraviolet to infrared.

Conclusion: Hubble's Legacy and the Future of Astronomy

After 34 years, Hubble remains a symbol of scientific exploration. Its achievements, from uncovering dark energy to imaging distant planets, have made the universe a more familiar place. With the emergence of telescopes like James Webb, Hubble remains a cornerstone of our understanding of space, reminding us that great discoveries always begin with a small step upward.