30 Years in Orbit: The Legacy of the Hubble Telescope
Imagine looking at the dazzling tapestry of thousands of galaxies and other celestial bodies, roaming through the boundless vastness of space, some of which date back to only a few million years after the Big Bang. An image of this scenario was possible because of the Hubble Space Telescope.
The Hubble Space Telescope (HST) is a NASA-launched space observatory and astronomical instrument that was launched on April 24, 1990. It is one of history’s most renowned and groundbreaking astronomical observatories. It was launched into Earth’s orbit and has played a critical role in expanding our understanding of the universe, revealing distant galaxies, nebulae, and celestial phenomena, and revealing the cosmos’ breathtaking beauty and mysteries.
The Hubble Telescope was named after American astronomer Edwin Hubble. Edwin Hubble was a pioneer in the field of observational cosmology, making numerous significant contributions to our understanding of the universe. His important discoveries include the expansion of the Universe, Redshift Measurements, Distance to Andromeda, Hubble’s Law (Rate of expansion of the universe), etc. Therefore, it was done to honor his groundbreaking work.
History of the Hubble Telescope
Lyman Spitzer, an American astrophysicist who made discoveries like Stellar Dynamics and Interstellar Medium, proposed the concept for the Hubble Space Telescope in 1946, but formal planning did not begin until the 1970s. The telescope was built in the 1980s as a result of a collaborative effort from NASA, the European Space Agency, and other partners. Construction of the HST was a complex and costly endeavor. Hubble was launched in 1990, but it initially had a faulty primary mirror(light-gathering surface of a telescope), which was fixed during a 1993 servicing mission. Hubble’s lifespan and capabilities were extended by subsequent servicing missions in 1997, 1999, and 2002.
Now, let’s get to the important section. Here are some of the most significant and groundbreaking discoveries:-
Determining the Age of the Universe: This is one of the most significant findings made by the Telescope. Hubble’s observations of Cepheid variable stars in distant galaxies helped in the improvement of the Hubble constant estimate, which is critical for establishing the age of the universe. It was essential in determining that the universe is around 13.8 billion years old.
Deep Field Images: The Deep Field Images are photographs revealing distant galaxies and offer insights about the universe’s history, structure, and mysteries. This is probably the most important finding of the Telescope. These images have contributed to significant discoveries in the mysteries of dark matter and dark energy. They have also revealed information about the Big Bang as some galaxies in the picture date back just a few million years after the Big Bang.
Exoplanet Atmosphere: Hubble has played a pivotal role in characterizing the planets, exoplanets, and stars outside our solar system. This is a crucial step in the search for potentially habitable worlds and in developing the process of space colonization. The first-ever detection of a molecule in the atmosphere of an exoplanet, specifically sodium in the atmosphere of HD 209458b, a hot Jupiter-like exoplanet was done by Hubble. Hubble has consistently observed exoplanet atmospheres, offering insights into composition, temperature, and weather. Discoveries of water vapor, methane, carbon dioxide, and carbon monoxide were done on planets to contribute to determining their habitability.
Confirming Supermassive Black Holes: A key role has been played by Hubble in confirming the existence of supermassive black holes in the center of galaxies, including the Milky Way galaxy. Hubble provided strong evidence for the presence of a supermassive black hole with a mass of about 4 million times that of the Sun, known as Sagittarius A* in the galactic center(center of our galaxy). It has also proved that supermassive black holes are located in the center of many galaxies.
Limitations and Challenges of the Hubble
The Hubble also faces several difficulties despite in marvelous discoveries. Since it was launched more than 3 decades ago, it poses aging hardware and is more prone to equipment failure. Data transfer and storage challenges have been mitigated over time. Hubble is also solar-powered powered which limits continuous observations. Hubble cannot also respond immediately to sudden astronomical events due to its distance from the Earth. The servicing missions to repair and upgrade Hubble are also complex and expensive and add significant costs to its operational life. It contends with residual atmospheric interference and a small aperture size which hinders in capabilities.
Despite this, the Hubble Space Telescope is still operational and functional as of 5th November. It has operated for over 31 years and is still productive. In June 2023, Hubble experienced a problem with its payload computer (control and management unit), which caused it to stop collecting science data. However, NASA engineers were able to switch the spacecraft to backup hardware, and Hubble returned to full science operations in July 2023.
Conclusion
In conclusion, the Hubble has provided deep insights into space and celestial objects with its transformative discoveries and stands as an emblem of humanity’s cosmic understanding. It has also engaged the public several times in space science. Its legacy stands unwavering and has provided inspiration for future telescopes such as the James Webb Space Telescope (JWST). It has had a big impact on this cosmic world.
