From breathtaking snapshots of distant galaxies to game-changing discoveries about the universe’s enlargement, the Hubble Space Telescope (HST) has dazzled humankind for 35 years.
After launching on April 24, 1990, Hubble overcame early flaws to grow to be one among NASA’s best triumphs. Its vivid pictures and numerous scientific breakthroughs have reshaped our understanding of the cosmos, inspiring new generations of telescopes and astronomers. To have fun Hubble’s majestic journey for greater than three a long time, NASA not too long ago launched a assortment of hanging pictures captured by the HST.
The Hubble Space Telescope being deployed on April 25, 1990.
| Photo Credit:
NASA
The US astronomer Lyman Spitzer proposed the concept of the Large Space Telescope in the Nineteen Forties. NASA and the US Congress accredited the mission in 1969 however confronted finances pressures. Then the European Space Agency chipped in with 15% of the LST’s price in change for 15% of its commentary time.
The HST, named for astronomer Edwin Hubble, was deliberate in 1979 and constructed by 20 corporations, universities, and the European Space Agency. It was initially scheduled to be launched in 1986 however that was delayed till 1990 due to technical difficulties and the Space Shuttle Challenger catastrophe.
This Hubble Space Telescope picture captures two clusters filled with large stars that could be in the early levels of merging. The 30 Doradus nebula, additionally extensively referred to as the Tarantula Nebula, is roughly 170,000 light-years from Earth. It is a part of the Large Magellanic Cloud, a galactic satellite tv for pc of the Milky Way.
| Photo Credit:
NASA, ESA
The HST first had two cameras: the Wide-Field and Planetary Camera (WFPC) and the Faint Object Camera. It additionally had two spectrographs: the Goddard High-Resolution Spectrograph (GHRS) and the Faint Object Spectrograph (FOS). A high-speed photometer onboard detected mild from high-energy sources. Three fine-guidance sensors put in in 1990 made high-precision measurements of the positions of celestial objects.
This view of the Butterfly Nebula from near-ultraviolet to near-infrared helped researchers higher understand the mechanics at work in its technicolor “wings” of fuel. The star or stars at the nebula’s middle are answerable for its look.
| Photo Credit:
NASA, ESA, and J. Kastner (RIT)
The WFPC was the hottest. It consists of two cameras. The Wide-Field digicam coated massive sky areas whereas the Planetary Camera magnified and improved picture decision. The Faint Object Camera captured mild from distant celestial objects with assist from a picture intensifier.
The scattered stars of the globular cluster NGC 6355 are strewn throughout this picture from the Hubble Space Telescope. NGC 6355 is a galactic globular cluster that resides in our Milky Way galaxy’s inside areas. It is lower than 50,000 light-years from the earth. Globular clusters are secure, tightly sure teams of hundreds to thousands and thousands of stars related to all kinds of galaxies. Their dense populations of stars and mutual gravitational attraction give these clusters a roughly spherical form.
| Photo Credit:
ESA/Hubble & NASA, E. Noyola, R.
Scientists and engineers took a number of weeks to test the HST’s management and communication methods earlier than astronomers working at the Space Telescope Science Institute in Baltimore might see its first pictures.
Shortly after launch, the HST’s images have been blurred, later discovered to be as a result of the telescope’s mirror had been floor to the mistaken form. Ground crew members quickly got here up with a corrective gadget: a sequence of smaller mirrors known as COSTAR to compensate for the main mirror’s defect.
F. Story Musgrave (foreground) and Jeffrey A. Hoffman are pictured close to the finish of the first spacewalk in December 1993 to repair the Hubble Space Telescope.
| Photo Credit:
NASA
Astronauts launched in 1993 applied this repair on the HST, by that point in earth orbit. They eliminated the high-speed photometer to make method for COSTAR, in addition to changed the WFPC with the WFPC 2, amongst different upgrades.
The telescope skilled a related downside in 1997. The evaluation of sunshine is of nice significance in house analysis. Blue mild has a shorter wavelength and purple mild has a longer wavelength. If the frequency of incoming mild bluer, it means the mild supply is transferring in the direction of the observer. If the frequency is turning into redder, the object is transferring away. The HST’s GHRS and FOS units, which carry out this evaluation, labored nicely till 1997. NASA subsequently changed them with the Space Telescope Imaging Spectrograph that 12 months. This gadget can analyse frequencies of sunshine from the ultraviolet to the infrared.
The telescope’s antenna transmits roughly 150 Gb of information a week. According to NASA, the HST has noticed virtually 52,000 stellar objects in 1.6 million observations since launch.
One of the HST’s most important achievements was to get scientists the knowledge with which they estimated the universe’s age. Before the telescope got here alongside, astronomers didn’t know if the universe was 10 billion years previous or 20 billion. To get the reply, astronomers checked out the Cepheid variable stars — a kind of star that pulsed in a regular method, its brightness various over intervals of days or months.
| Photo Credit:
NASA
Astronomers might decide the distance to such a star utilizing its luminosity and pulsation charge. Based on that measurement, they may then estimate the distances to numerous different, extra distant celestial objects. Finally, primarily based on all the knowledge, astronomers might estimate how briskly the universe was increasing, and work again from there to the universe’s age.
With the HST’s eager observations, they recognized greater than 800 Cepheid stars in 24 galaxies and thereon that the universe was round 13.8 billion years previous.
Astronomers have additionally created a 3D map of darkish matter utilizing knowledge from the HST and different telescopes. The telescope has additionally discovered that gamma-ray bursts, the universe’s most energetic explosions, happen in galaxies with speedy star formation and a low proportion of parts heavier than helium.
Numerous galaxies had supermassive black holes at their centres — or so astronomers believed by the early Nineteen Nineties, and the HST the perception’s underlying assumptions. Closer house, the HST helped discover two further moons of Pluto (Nix and Hydra) and noticed seasonal alterations on Pluto’s floor. Its knowledge helped estimate the mass of Eris, the photo voltaic system’s heaviest dwarf planet, and primarily based on that indicated the existence of extra such objects in the Kuiper Belt and past.
| Photo Credit:
NASA, ESA, H. Weaver (JHU/APL), A. Stern (SwRI), and the HST Pluto Companion Search Team
The HST additionally first studied the ambiance of an exoplanet: HD 209458-b, a.ok.a. Osiris, a scorching world positioned 150 lightyears away. Osiris was discovered to be inside 6.4 million km of its host star and thus a floor temperature of round 1,100° C.
The HST was initially anticipated to function for 15 years nevertheless it has persistently delivered over the final 35 years and continues to achieve this. Astronomers commemorated the anniversary of its launch with a gorgeous picture of NGC 1333, a star-forming space positioned 967 light-years away in the Perseus molecular cloud.
It is unimaginable to overstate the HST’s delight of place in our understanding of the cosmos. Every pixel of its pictures has revealed complete new worlds in the nice past, serving to us understand our personal place in the cosmos.
Shamim Haque Mondal is a researcher in the Physics Division, State Forensic Science Laboratory, Kolkata.
Published – May 05, 2025 09:08 am IST
