The Hubble telescope was launched by NASA (National Aeronautics and Space Administration) and ESA (European Space Agency) on April 24, 1990. Space Shuttle Discovery launched it into orbit.
The Hubble telescope orbits approximately 547 km above Earth. travels 5 miles per second and is solar-powered; hence, it gets energy from the Sun. Hubble takes clear and sharp images of the celestial bodies in space e.g., planets, stars, galaxies, and nebulae. It can take images of celestial bodies, which are billions of light-years away from us.
Hubble has made countless astonishing discoveries about celestial bodies many light-years away. It made discoveries that totally changed our perception of the universe. One of the greatest images this telescope took was the Hubble deep field, which is an image of a small region in the Ursa Major constellation. Even though Hubble uncovered new chapters of the universe, it still has limited sight.
All the colorful dots you see in the picture above are individual galaxies and this makes you wonder how enormous the universe is and how small we are. These galaxies may seem uncountable, but they are just the ones from a tiny spot we can see in the sky. You can even find more Hubble deep field images on NASA and ESA websites.
This wasn’t the only astonishing image; it took many other images of planets, stars, nebulae, and galaxies. However, the limitations of this telescope make its sight limited.
Hubble can only see visible light from a certain point of the electromagnetic spectrum.
Therefore, only the light from the range of wavelengths that the telescope’s instruments can observe is captured. Therefore, the visible light that has a longer wavelength than that of which Hubble can see is not visible to it. This is the main reason why Hubble can’t see the galaxies that existed in the early universe because the wavelengths of their light are much longer.
Moreover, another factor that adds to this disability is the expansion of the Universe. Many of you may know the Doppler effect. An example of it is when an ambulance is blowing its siren close to you, you can hear the sound very loudly because the pitch of the sound is high due to the shorter wavelengths of sound; however, as the ambulance goes further away from you, the pitch of the sound gets lower and the wavelengths are longer and hence, you hear the sound slower.
The same effect happens with light when the universe expands. When the universe expands, the wavelengths from distant objects also expand and due to this, Hubble can’t capture the longer wavelengths because they are out of its reach. However, we shouldn’t just give up. Space scientists are filling this pothole by creating another telescope that will see what Hubble could not and that telescope is the James Webb Telescope.
The making of this telescope is the largest, most expensive, and most challenging space-engineering project humans have ever attempted. NASA has been working on this project for 30 years and it is called The James Webb Telescope. The James Webb telescope can take images in more detail and at higher distances than the Hubble telescope and can see objects that have details about the origin of the universe. This telescope will help us understand how the universe started and how it formed. It would uncover the forces of the universe and the evolution of celestial bodies. Not only will this telescope help us see the past of this universe, but it will also help us predict the fate of many of the galaxies, stars, etc.
Furthermore, this telescope has the ability to capture infra-red light that ultimately helps it in finding objects much farther than the Hubble could see. A major problem though, is that the Sun also emits infra-red light so, how do we keep the infra-red light from the Sun away? Well, this telescope has a sun shield that blocks all the light from the Sun from reaching the telescope’s camera.
However, scientists still have a lot of problems to tackle before launching. One problem is what we all have to pray to end well. That problem is the launch. We know that rocket launches are extremely difficult and have a high chance of failure. Therefore, we have to launch this telescope perfectly into space or else, a lot of money, effort, and time will be wasted.
This telescope will be launched into orbit at a very far distance, at a point called the Second Lagrangian point. This point in orbit is 1.5 million km away from the Earth though it is still in the zone of orbiting the Earth. The advantage of this orbit is that it would clear out a huge space for the telescope to see.
If this telescope successfully gets into orbit and everything works as it is meant to be, this telescope will change our perception of the universe and will make history, since it will be able to see parts of the universe that no human has seen yet.
The writer is a student of Grade 10 who writes about Astronomy and Climate Change.