Knowing more about the space that surrounds the Earth has been one of the greatest obsessions of the human being for several decades. Little by little, the study of the planets closest to us is becoming a reality, but the known universe (and yet to be known) is still too far away. To begin studying it, space telescopes are necessary, and for a few months the most recent, known as James Webb, has already been in space. In this article we are going to see its main characteristics, as well as the differences with the previous Hubble telescope.
This new space telescope, which went into space as if it were a satellite, was launched last December to take over from the Hubble telescope. With so many years between the two telescopes, it is logical that there is a clear technological leap, which will allow scientists to learn much more about space.
Differences between the James Webb and Hubble Telescope
As in all kinds of technology, over the years it becomes better and even reduced. This will not be different in space telescopes, despite the fact that they are real “monsters”. We will now review the differences between the two.
Size
Let’s start with the most obvious difference between the two, which is in size. One might think that being a new technology, James Webb should be smaller and more compact than the Hubble telescope, but it is quite the opposite.
James Webb Telescope (NASA)
The James Webb telescope is actually 21 meters long by 14 meters wide, which is roughly the size of a tennis court (23.77 x 10.97 for doubles) and much larger than the Hubble telescope. , which is 13 meters long. Of course, in terms of weight, the James Webb wins the street: it weighs almost half.
the main mirror
Continuing a bit along the lines of the previous section, we also have to talk about the dimensions of the main mirror of each telescope. The mirror of the Hubble telescope measured 2.4 meters, a figure that is widely exceeded by the James Webb, which measures 6.5 meters.
Mirrors by James Webb (NASA)
This difference is extremely important between the two, since the larger the mirror, the greater the distance that can be seen with the telescope. In fact, the fact that the mirror is so larger than Hubble is due to the main objective of the new telescope, which is none other than being able to see the first light emitted by the universe. As a curiosity, the mirror is made of gold-coated beryllium.
Field of view
In the field of view of both telescopes we are going to see a quite remarkable difference, given above all by the technological evolution that has taken place in recent years. Hubble has served scientists very well, but with James Webb they will be able to see a greater breadth of space.
In fact, it is estimated that James Webb’s field of view is approximately twice that of Hubble, which is why we talk about such a difference.
Infrared vs Ultraviolet
We come to the key differentiating point between the two space telescopes. While the Hubble telescope focused on the visible spectrum of light, the James Webb telescope will use technology to view the infrared spectrum.
Image captured by Hubble (NASA)
This will make the James Webb Space Telescope capable of capturing much more than Hubble, especially in areas where there is a lot of gas and dust, since with infrared it will be able to “penetrate” these masses to see beyond.
Distance from Earth
The distance between the Earth and both satellites is also quite different. The Hubble Telescope was launched to orbit the Earth, and in fact it is approximately 600 kilometers above us.
On the other hand, the James Webb Space Telescope will not orbit the Earth, but rather the Sun. That will make it very far from our planet, specifically 1.5 million kilometers away.
Price
A detail that you might not have thought to find in this list of differences, but the truth is that building both involved quite different investments. Keep in mind that the Hubble telescope was launched in 1990, and the value of the dollar was not what it is today.
Regardless of this, we are talking about differences between the two, and there is also a difference in price. While Hubble cost $2.8 billion, the James Webb Telescope has cost close to $10 billion, making it the most expensive and sophisticated space telescope ever created by man to date.
Service life and repairability
The Hubble telescope has surprised all scientists due to its great longevity. This has lasted more than 30 years in operation, thanks above all to various adjustments and fixes that have been made to it during all this time. The James Webb would have a useful life of 5 years, although it is expected to reach up to 10 years.
Hubble Telescope (NASA)
However, the real problem of the useful life of this will depend on another factor that we have already seen earlier in this list: the distance from Earth. Since it will orbit the sun and not the Earth, it will be really difficult to send a mission to fix it, something that has not happened with Hubble.
