How did the Solar System form?
What was the Universe like when it was very young?
What are planets around other stars like?
Over the last 26 years,
Hubble has provided answers to these and many other questions.
However, even the best of telescopes needs a colleague...
… and that’s where the James Webb Space Telescope comes in.
A cosmic double act: Hubble meets James Webb
Launched in 1990,
the Hubble Space Telescope has been incredibly successful, and has not only reached, but exceeded, all of its targets.
In doing so it completely changed our view of the Universe.
Hubble has been undeniably brilliant,
but there are some parts of the Universe that it just cannot see.
Enter Hubble's future colleague, the James Webb Space Telescope!
This magnificent telescope is a joint venture between NASA,
the European Space Agency and the Canadian Space Agency.
James Webb’s infrared view of the Universe will peer through obscuring dust
to reveal the delicate structures of the star-forming regions beneath,
probe light from the first galaxies and stars,
and much, much more.
But what makes these two amazing telescopes different?
Firstly, James Webb is huge for a space telescope.
Hubble’s 2.4 metre mirror might be large
but it is simply dwarfed by James Webb’s 6.5 metre mirror.
This allows James Webb to detect much fainter objects.
Hubble was also designed to be serviced by visiting astronauts,
swapping out instruments and faulty components.
For James Webb, this won’t be possible.
And not only will Webb be alone, it will also be cold — very cold —
operating at around -240 °C.
Because it has to operate at incredibly cold temperatures,
James Webb can’t be built in the same way as Hubble.
It has to carry its own huge sunshield to keep the telescope cool.
The telescope and the sunshield are so big
that James Webb will have to unpack itself once launched.
It is a great feat of engineering.
Everything for the telescope has to be built at room temperature,
but still needs to be aligned and working properly when it is cooled down
— which changes the size of the components inside.
Keeping James Webb cold is the reason behind another big difference between it and Hubble.
Whilst Hubble orbits the Earth at around five hundred kilometres,
James Webb has a very different path — not in orbit around the Earth
— that will keep it one and a half million kilometres from Earth.
With this new player out there observing the skies,
and Hubble still active,
who knows what we will find!