30 Years of Hubble Space Telescope

30 Years of Hubble Space Telescope

30 Years of Hubble Space Telescope
Image Credits: BBC

NASA celebrated the 30th birthday of HST by releasing another gem of an image from interstellar space.

During the 1960s, NASA began planning for a space telescope that could take clearer pictures of the universe. After nearly 3 decades of efforts, the Hubble Space Telescope was deployed into Earth’s orbit on 24th April 1990.

The space shuttle “Discovery” (with a five-man crew) was used to carry Hubble into space. Since then, HST has exceeded all the expectations of both scientists and the public.

Historical Background of Hubble Space Telescope

Hubble is named after an American astronomer, Edwin P. Hubble. He made important discoveries in the early 1900s and is often called the “Pioneer of the Distant Stars”. He was the one who proved that Milky Way is not the only galaxy in our universe.

Hubble Space Telescope

In contrast to its massive achievements, Hubble is not very big. It has the length of a large school bus and weighs as much as two adult elephants. This space telescope stays 550 kilometers above Earth and orbits at 3 kilometers per second. Therefore, it would take HST only 10 minutes to reach the western coast of the US from the eastern coast.

The secret to Hubble’s longevity is the fact that it is a solar-powered telescope. Its massive solar panels use the light from the Sun to generate the necessary power.

The launch of this telescope was not that smooth because it suffered numerous challenges. In the beginning, this $1.5 billion project was hard to sell, and funding was denied a few times. In 1975, NASA got buy-in from the European Space Agency, which shared the cost. The funding was approved by Congress in 1977 and the development of Hubble was started.

The program was delayed once more, after the explosion of space shuttle Challenger in 1986. Later on, a few defects were found in the telescope’s reflective mirror that delayed the launch, even further. After overcoming all these hurdles, the HST was finally launched in 1990.

Importance of Hubble

So why was Hubble Space Telescope needed? There are numerous giant telescopes and observatories on Earth that are used for observing space. However, their efficiency is limited because the Earth’s atmosphere refracts and alters the light coming from space.

Hubble provides the solution to this problem as it orbits above the atmosphere of Earth. Consequently, the images taken by this space telescope are not affected by the Earth’s blurring atmosphere. This gives us a better view of the universe than the telescopes that are on the ground.

Another thing that makes Hubble important is that it carries a plethora of instruments. For instance, the Fine Guidance Sensors lock onto nearby stars and point Hubble in the right direction. The telescope can lock onto a target that is one mile away, almost without moving.

Once HST acquires a target, its primary mirror starts to collect light. This mirror can collect 40,000 times more light than the human eye. The light bounces off the primary mirror to the secondary mirror. The secondary mirror focuses the light back through a hole in the primary mirror. From there, the light shines to Hubble’s scientific instruments.

Main Instruments

Hubble Space Telescope has the following main instruments.

  • Wide-field camera
  • Advanced camera for surveys
  • Infrared camera
  • Cosmic Origins Spectrograph
  • Space Telescope Imaging Spectrograph

All these instruments allow HST to take images of both near and distant objects.

Important Discoveries of Hubble Space Telescope

Hubble Ultra Deep Field

First and foremost, HST has helped scientists to determine the age and size of our universe. Similarly, it has also allowed scientists to understand how stars and galaxies form. An image called “Hubble Ultra Deep Field” shows the farthest galaxies that can be seen.

The list of discoveries doesn’t end here. Hubble has massively helped in the discovery of Dark Matter, a force that expands the universe. It has detected Black Holes, which are massive vacuums in space that swallow everything (including light). Recently, Gamma-ray Bursts were also detected by using this telescope.

Gamma-ray Burst

Happy 30th Birthday

On 24th April 2020, NASA released a never-seen-before view of two Nebulas (NGC 2020 and NGC 2014). This extraordinary image is called the Tapestry of Blazing Starbirth. You can enjoy the stunning view of these nebulas in the video below.

On this occasion, Dr. Jennifer Wiseman (Senior Project Scientist) also described the status of the Hubble Space Telescope. He said,

“So, is the telescope nearing its end? No.”

HST was designed to be repaired ad upgraded while being in orbit. Hubble’s longevity can be attributed to five space shuttle servicing missions from 1993 to 2009. During these missions, astronauts upgraded the telescope with advanced instruments, new electronics, and on-orbit repairs. HST is expected to work alongside the upcoming James Webb Space Telescope.

Leave a Reply

Your email address will not be published. Required fields are marked *