Hubble – The Floating Marvel- Part- I
One of the greatest scientific quests of the entire human race is its attempts to unlock the secrets of Universe. The advancements in space technology and the prolific improvements achieved in the making of optical instruments have paved way to realize this eternal human dream. The progresses thus made are step by step improvements, with an undying hope to find the holy grail of astronomy, to catch the glimpse of the inception of the universe.
The Hubble Space Telescope, though not the first of the space telescopes launched in 1990 and is still operational, has provided priceless chunks of scientific data, which has enabled us to understand the Universe much better than ever. Though astronomy is one of the oldest sciences and many mile stone moments and discoveries have been constantly made over the timeline that sprawls millennia, the progress made in understanding the Universe in the past two decades is tremendous. Undeniably Hubble’s contribution is one of the key factors for this.
Hubble Space Telescope, one of the most ambitious projects of NASA, was launched in April 1990 from Kennedy Space Center. Stationed at an orbital height of 559 km above ground, the telescope houses a 2.4 m diameter aperture telescope. The telescope is stationed outside the turbulent earth’s atmosphere, thus enabled it to make never before high resolution images. The images thus made by Hubble provided unprecedented view of space, the first of its kind, then. Scientists were able to collect huge amount of data and it gave the astrophysicists a gold mine of data to dig in. Even after 23 years of service this floating engineering marvel is still going strong.
In fact the telescope on proposal had 3m diameter mirror, but budgetary constraints reduced the size to 2.4m. The project which got approval of the US Congress in the 70s had seen many cuts in the funds over time. The original launch had been planned by 1983, yet due to various delays and constraints it was finally launched on April 24, 1990. The telescope is named after Edwin Hubble, one of the pioneering American astronomers, who was the first to prove our Universe is expanding. Hubble on board has four main instruments, which are capable of observing the near UV (Ultraviolet), visible and near IR (Infrared) spectra. The photographs taken in the spectral regions other than the visible region of the electromagnetic spectrum threw new light in understanding the secrets of the cosmos.
Soon after the launch the first photographs sent back to the earth though were good for that time, didn’t produce expected details. The maiden photographs only showed serious flaws in the optical system in the telescope. Analysis revealed that epicenter of the problem lied in the wrong ground primary mirror by many nanometers than the prescribed value. It caused severe spherical aberrations in the images taken. This proved catastrophic and messed up the entire project. We shall see the remedial steps taken to overcome this hurdle and the achievements of this floating scientific marvel, in the next post.