James Webb Space Telescope: What is the Nasa mission and when did it launch?

Nasa has released a stunning “teaser” image from the James Webb Space Telescope.

It comes ahead of next week’s long-awaited wider release of images from the telescope showing what Nasa says will be “unprecedented and detailed views of the universe”.

The scientists behind the project have billed the test image (pictured below) “among the deepest images of the universe ever taken”.

Nasa's test image from the James Webb Space Telescope. (Nasa)
Nasa's test image from the James Webb Space Telescope. (Nasa)

The teaser will not be used as part of next week’s release. Nasa said it was not used to provide scientific observation, “rather… to test how well the telescope could stay locked onto a target, but it does hint at the power of the telescope”.

The image, Nasa says, shows “bright stars standing out with their six, long, sharply defined diffraction spikes – an effect due to [the telescope’s] six-sided mirror segments. Beyond the stars, galaxies fill nearly the entire background.” It represents 32 hours of exposure time.

But what is the James Webb Space Telescope, what is its purpose and why is it such a major project in the astronomy sector? Here, Yahoo News UK explains all…

What is the James Webb Space Telescope?

Also known as “Webb”, the James Webb Telescope is the most powerful telescope to have been launched into space.

It was launched on Christmas Day last year as part of a decades-in-the-making project to expand scientists’ knowledge of the universe.

Arianespace's Ariane 5 rocket with NASAs James Webb Space Telescope onboard lifts up from the launchpad, at the Europes Spaceport, the Guiana Space Center in Kourou, French Guiana, on December 25, 2021. - The telescope, the most powerful space observatory ever built, is now tentatively set for launch on Christmas Day, after decades of waiting. An engineering marvel, it will help answer fundamental questions about the Universe, peering back in time 13 billion years. (Photo by jody amiet / AFP) (Photo by JODY AMIET/AFP via Getty Images)
The launch of the rocket with Nasa's James Webb Space Telescope onboard on Christmas Day last year. It launched from Kourou, French Guiana. (AFP via Getty Images)

It is aiming to discover more about the formation of stars and galaxies, and to determine how the first galaxies formed - meaning it has the potential to make breakthroughs in the field of astronomy.

If successful, it will give scientists valuable insight into space matter as it aims to discover details of the mystery substance that makes up the vast majority of matter.

In fact, Christopher Evans, project scientist from the European Space Agency (ESA), said the observations are expected to change the face of astronomy forever.

Read more: Nasa’s Webb telescope is a joy. But it’s the private ventures that push at limits (from January)

“We’re really excited to see the first observations in the summer,” Evans said in May. “Because I think astronomy is not going to be the same again once we see what this can do with these first observations.”

The mission is led by Nasa, the ESA and the Canadian Space Agency, with the UK having played a major role by leading the European Consortium which designed, built and tested the Mid-Infrared Instrument (MIRI). This is the key instrument on the telescope, and is able to see the faint light from the most distant stars.

The project has been in the making since 1996.

When will Nasa reveal the telescope's first images?

The first full-colour images and spectroscopic data from the telescope, offering "unprecedented and detailed views of the universe", will be released on Tuesday (12 July).

Each image will be released in a live Nasa broadcast starting at 2.30pm UK time.

It will consist of cosmic objects Webb targeted for these first observations, including:

  • Carina Nebula: one of the largest and brightest nebulae (stellar universes where stars form) in the sky, located 7,600 light-years away in the southern constellation, Carina. It is home to many massive stars, several times larger than the sun

  • WASP-96 b (spectrum): a giant planet outside the solar system, composed mainly of gas and located nearly 1,150 light-years from earth. Its discovery was only announced eight years ago

  • Southern Ring Nebula: a planetary nebula - an expanding cloud of gas, surrounding a dying star - nearly half a light-year in diameter and located approximately 2,000 light years away from earth

  • Stephan’s Quintet: about 290 million light-years away, located in the constellation Pegasus. It was the first compact galaxy group ever discovered in 1787